DRAFT UGANDA STANDARD  
  DUS DEAS  903 
First   Edition  
2020 -mm-dd 
 
 Reference number  
DUS DEAS  903: 2016 
© UNBS 2020  
   
Welded steel tanks for liquefied petroleum gas (LPG) — Road 
tankers — Design and manufacture  
 
 DUS DEAS  903: 2016 
ii                © UNBS  2020  - All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its correct application  
© UNBS 2020  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior writte n 
permission from UNBS.  
Requests for permission to reproduce this document should be addressed to  
The Executive Director  
Uganda National Bureau of Standards  
P.O. Box 6329  
Kampala  
Uganda  
Tel: +256 41 7 333 250/1/2  
Fax: +256 41 4 286 123  
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  
 DUS DEAS  903: 2016 
© UNBS  2020  - All rights reserved                 iii National foreword  
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and 
Cooperatives established under Cap 327, of the Laws of Uganda, as amended.  UNBS is mandated to co -
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO).  
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of representative s of 
consumers, traders, academicians, manufacturers, government and other stakeholders.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments  before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
This Draft Uganda Standard, DUS DEAS  903: 2020 , Welded steel tanks for liquefied petroleum gas (LPG) — 
Road tankers — Design and manufacture , is ide ntical with and has been reproduced from an East African  
Standard, DEAS  903: 2020 , Welded steel tanks for liquefied petroleum gas (LPG) — Road tankers — Design 
and manufacture , and is being proposed for adoption as a Uganda Standard.  
The committee responsible for this docu ment is Technical Committee UNBS/TC 16, Petroleum . 
Wherever the words, “ East African  Standard " appear, they should be replaced by "Uganda Standard."  
 
 
 
 
  DEAS 903:  2016 
ICS   
© EA C 2016                   First Edition 2016  
DRAFT EAST AFRICAN STANDARD  
Welded steel tanks for liquefied petroleum gas (LPG) — Road 
tankers — Design and manufacture  
EAST AFRICAN COMMUNITY  DEAS 903: 2016  
ii © EAC  2016  – All rights reserved  
 Copyright notice  
This EAC document is copyright -protected by EAC. While the reproduction of this document by 
participants in the EAC standards development process is permitted without prior permission 
from EAC, neither this document nor any extract from it may be reproduced, stored or 
transmitted in any form for any other purpose without prior written permission fr om EAC.  
Requests for permission to reproduce this document for the purpose of selling it should be 
addressed as shown below or to EAC’s member body in the country of the requester:  
© East African Community 2013  — All rights reserved  
East African Community  
P.O. Box 1096  
Arusha  
Tanzania  
Tel: +255 27 2504253/8  
Fax: +255 27 2504481/2504255  
E-mail: eac@eachq.org  
       Web: www.eac -quality.net  
Reproduction for sales purposes may be subject to royalty payments or a licensing agreement. 
Violators may be p rosecuted . DEAS 903: 2016  
© EAC 2016  – All rights reserved  iii 
 Foreword  
Development of the East African Standards has been necessitated by the need for harmonizing 
requirements governing quality of products and services in the East African Community. It is 
envisaged that through harmonized standardization, trade bar riers that are encountered when goods 
and services are exchanged within the Community will be removed.  
In order to achieve this objective, the Community established an East African Standards Committee 
mandated to develop and issue East African Standards.   
The Committee is composed of representatives of the National Standards Bodies in Partner States, 
together with the representatives from the private sectors and consumer organizations. Draft East 
African Standards are circulated to stakeholders through the  National Standards Bodies in the Partner 
States. The comments received are discussed and incorporated before finalization of standards, in 
accordance with the procedures of the Community.  
East African Standards are subject to review, to keep pace with tec hnological advances. Users of the 
East African Standards are therefore expected to ensure that they always have the latest versions of 
the standards they are implementing .  
DEAS  903 was prepared by Technical Committee EASC /TC 038                                              
 DRAFT EAST AFRICAN STANDARD  DEAS 903: 2016  
 
© EAC 2016  – All rights reserved  1 
 Welded steel tanks for liquefied petroleum gas (LPG) — Road 
tankers — Design and manufacture  
1 Scope  
This draft East Africa Standard specifies minimum requirements for materials, design, construction 
and workmanship procedures, and te sts for welded LPG road tanker tanks and their welded 
attachments manufactured from carbon, carbon/manganese and micro alloy steels.  
This standard does not cover tanks for ISO type containers.  
2 Normative references  
 
The following referenced documents are indispensable for the application of this East Africa Standard. 
For dated references, only the edition cited applies. For undated references, the latest edition of the 
referenced document (including amendments) applies:  
ISO 6892-1, Metallic materials -- Tensile testing -- Part 1: Method of test at room temperature  
ISO 148 -1, Metallic materials — Charpy pendulum impact test —Test method  
ISO 17636 -2 Non-destructive testing of welds -- Radiographic testing -- Part 2: X - and gamma -ray 
techniques with digital de tectors  
ISO 11484,  Steel products — Employers qualification system for non -destructive testing (NDT) 
personnel  
ISO 6520 -1, Welding and allied processes — Fusion welding  
ISO 6520 -2, Welding and allied processes — Classification of geometric imperfection in metallic 
materials — Welding with pressure  
CD/K/1:2016 ; Inspection and testing of LPG road tankers  
ISO 9328 -2, Steel flat products for pressure purposes -- Technical delivery conditions -- Part 2: Non -
alloy and alloy steels with specified elevated temperat ure properties  
ISO 9692.  
 
3 Terms and definitions  
 
For the purposes of this East Africa Standard, the following terms and definitions apply:  
 
3.1 
yield strength  
upper yield stress ReH or, for steels that do not exhibit a definite yield (non -proportional el ongation), 
the 0.2 % proof stress  
 
3.2 
cold forming  
process of deforming metal plastically under conditions of temperature and strain – hardening, usually, 
but not necessarily conducted at room temperature  DEAS 903: 2016  
2 © EAC  2016  – All rights reserved  
 3.3 
hot forming  
process where metal are plasticall y deformed above their recrystallization temperature  
 
3.4 
sun shield  
shield covering not less than the upper third but not more than the upper half of the shell surface, 
separated from the shell by an air gap of at least 40 mm  
3.5 
road tanker tank  
assembly  of the shell (the pressure -retaining enclosure including the openings and their closures) and 
non-pressure -retaining parts welded directly to the shell  
3.6 
approving authority  
within the scope of the relevant competent authority(ies) in the partner states   
3.7 
notified/designated body  
testing and certifying body approved by the relevant authority(ies) in the partner states  
3.8 
competent person  
person who, by qualifications, training, experience and resources, is able to make objective judgments 
and is duly  authorised by the relevant authority(ies) in the partner states  
3.9  
LPG ( liquefied petroleum gas)  
is pure propane, butane or a mixture of the propane and butane  
3.10 
Parent material  
Materials to be joined by welding  to form a tank shell  
4 Materials  
 
4.1 Suitability  
 
Unless otherwise specified by the design documents, the design temperature range shall be -20 oC to 
+ 50 oC. The materials of construction shall be suitable for operating within the envisaged temperature 
range. If the tank could be subjected to mo re severe ambient or product temperatures, the design 
temperature range shall be -40 oC to + 50 oC. The materials of construction shall be resistant to brittle 
fracture and stress corrosion cracking within the envisaged temperature range.  
 
NOTE   Guidance o n selection of material grades is given in Annex A.  
 
4.2 Pressure retaining parts  
Pressure -retaining materials shall be of appropriate steels conforming to  ISO 9328 -2or shall conform 
to specifications agreed with the approving authority.  All materials shall conform to 10.2.4.5  and the 
ratio of the specified yield strength 
)(eHR to minimum tensile strength ( Rm) shall not exceed 0.85 (i.e 
0.85)  m eHR R
.  The percentage elongation at fracture shall be not less than 10 000 divided by the 
actual tensile strength in N/mm2, and in any case shall be not less than 16 % for fine grained steels 
and not less than 20 % for other steels.  DEAS 903: 2016  
© EAC 2016  – All rights reserved  3 
 . 
4.3 Non-pressure retaining parts  
 
Non-pressure retaining parts that are directly welded to pressure retaining p arts shall be of suitable 
materials or materials with characteristics approved by a competent authority.  All materials used for 
non-pressure retaining parts shall be compatible with the materials of pressure retaining parts, and 
shall conform to the impac t requirements of 10.2.4.5 . 
 
4.4 Welding consumables  
 
Welding consumables shall be able to provide consistent welds with properties at least equal to those 
specified for the parent materials in the finished tank.  
 
4.5 Non-metallic materials (gaskets)  
 
Non-metallic materials (gaskets) shall be compatible with both phases of LPG over the range of 
pressures and temperatures for which the tanker is designed . (see 4.1 and Annexes B and C).  
 
4.6 Certification of materials  
 
Pressure retaining parts and non -pressure  retaining parts directly welded to the tank shall be provided 
with the material manufacturers’ certificates.  
 
5 Tank design  
 
5.1 Design conditions  
 
5.1.1  Reference temperatures shall conform to Annex B.  
 
5.1.2  Design calculations shall be carried out in a ccordance with Annex D.  
 
5.1.3  Account shall be taken of the fatigue loading on all component parts of the tank and its 
attachments by conducting an assessment or through proven operating experience.  
 
5.2 Surge plates  
 
5.2.1  To reduce the dynamic loadings of the liquid content due to accelerations of the vehicle, 
tanks longer than 4 m shall be fitted with transverse surge plates at a maximum spacing of 4 m, and 
shall be designed to permit full internal inspection of the tank. The area of each plate shall be  at least 
70 % of the cross -sectional area of the tank in which the plates are fitted.  
 
5.2.2   Surge plates shall be able to withstand the load imposed by a full capacity liquid content of 
the section between the plates in either direction.  
 
5.2.3   Surge p lates shall be at least 2 mm thick.  
 
5.2.4   Provision shall be made for communication and drainage between sections.  
 
5.2.5   For tanks over 1.8 m diameter, having a wall thickness less than 6 mm and for tanks up to 
1.8 m diameter, having wall thickness les s than 5 mm, the surge plates shall have the same thickness 
as the shell and the volume between any two plates shall not exceed 7 500 L.  
 
5.3 Doubler plates  DEAS 903: 2016  
4 © EAC  2016  – All rights reserved  
  
5.3.1  To reduce stress concentration on the tank, load -carrying attachments shall incorporate a 
doubler plate between the attachment and the tank.  
 
5.3.2  Non-circular doubler plates shall be designed with as generous as practicable corner radii, 
with a minimum of 25 mm to reduce stress concentrations.  
 
5.3.3  If doubler plates are provided with test soc kets they shall be closed with threaded plugs after 
testing.  
 
5.4 Stresses due to motion  
 
5.4.1  Tanks and their permanent attachments shall be able to absorb, under maximum permissible 
load, forces exerted by the design pressure, and the following dynamic forces:  
 
a) In the direction of travel: twice the total mass times gravity;  
 
b) At right -angles to the direction of travel: the total mass times gravity;  
 
c) Vertically upwards: the total mass times gravity;  
 
d) Vertically downwards: twice the total mass t imes gravity.  
 
5.4.2   Under the forces defined above, the stresses in the tank and its fastenings shall not exceed 
the following:  
 
a) General membrane stress in the shell, remote from the supports which shall be calculated as 
the normal design stress as de fined in Clause D.1;  
 
b) Stresses local to the supports, determined either by experimental analysis or 
calculation/special analysis.  
 
5.5 Self-supporting tanks  
 
Self-supporting tanks shall be designed to carry bending stresses that would otherwise be carri ed by 
the chassis or frame.  
 
5.6 Vacuum conditions  
 
Tanks shall be designed to withstand vacuum conditions generated by the product during operation or 
other operational conditions, but as a minimum, this shall be equivalent to an external pressure of at 
least 40 kPa.  
 
5.7 Tanks mountings  
 
5.7.1  Mounting structures shall be fabricated in steel and designed to limit movement of the tank in 
relation to the chassis.  
 
5.7.2  Tank mountings and their method of attachment to the shell shall be of sufficient streng th to 
support the tank when full of water.  
 
5.7.3  The design of the tank mounts shall be co -coordinated with the design of the vehicle chassis. 
The designer shall assess the effect of the tank and its mountings, including the additional loadings 
given in 5 .4. DEAS 903: 2016  
© EAC 2016  – All rights reserved  5 
  
NOTE  The chassis manufacturer should be notified at the tank design stage that the tank, while on the chassis, could be 
subjected to a hydraulic test, during which the tank can contain twice the normal weight of carrying capacity.  
 
5.7.4  Tank mounting s designed as an integral attachment to the shell shall be fitted with doubler 
plates as specified in 5.3. Stitch welding shall not be used.  
 
5.8 Internal pipe work  
 
5.8.1   The mechanical strength of internal pipe work and supports shall be  strong enough  to 
withstand the service conditions, including dynamic load  as determined by the design calculations . 
 
NOTE  Internal pipe work may be attached directly to a tank boss.  
 
5.8.2   Pipe work shall be located so as to avoid inadvertent entry of liquid LPG from the liquid inlet 
line into other pipe work terminating in the vapour space.  
 
6 Openings  
 
6.1 General  
 
Valves and other accessories shall be protected against damage by external impact either by their 
positioning on the tank, when mounted on the vehicle, or  by specific tank design.  Provision in tank 
design shall be either by mounting and fitting valves and other accessories in a recess with the 
contour of the tank shell or end, or by use of a guard able to with stand a collision with another vehicle 
and the  forces experienced in a tank roll -over.  
 
6.2 Reinforcement of openings  
 
Openings shall be reinforced and designed in accordance with  Annex D.4. 
 
6.3 Threaded connections  
 
The maximum nominal diameter of threaded connections shall be 50 mm.  
6.4 Manhole  
 
6.4.1 Tanks over 1.5 m diameter shall be fitted with a manhole either:  
 
a) At least 500 mm in diameter; or  
 
b) At least 420 mm in diameter, if acceptable to the notified/designated body.  
 
6.4.2  Manholes shall be of forged construction, machined from plate, or fabricated from pipe and 
standard flanges of the appropriate temperature and pressure rating.  If plate is used for pad type 
manholes, it shall be ultrasonically tested for lamella defects.  
 
6.4.3  The manhole shall be positioned for safe egress and acce ss of an inspector.  
 
7 Non-pressure retaining parts  
 
7.1 Attachment welds  
 
Attachment welds shall be continuous.  
 DEAS 903: 2016  
6 © EAC  2016  – All rights reserved  
 7.2 Position of attachment welds  
 
Attachments shall be designed not to trap water and to permit inspection of the weld. Wherever 
possible, att achment welds shall be clear of vessel welds (longitudinal, circumferential and opening 
welds), by a minimum distance of 40 mm. Where this is not possible, attachment welds shall fully 
cross the main welds.  
 
8 Workmanship and construction  
 
8.1 General  
 
8.1.1 Road tanker tanks shall be manufactured , inspected and approved  in accordance with this 
standard. . 
8.1.2  The manufacturer shall be responsible for the competence, training and supervision of their 
staff.  
 
8.1.3  The manufacturer shall ensure, taking int o account any instructions from the material supplier 
that the materials of the finished tank conform to this standard . 
 
8.1.4  The manufacturer shall have defined procedures for manufacturing operations, including 
processes such as forming, welding and hea t treatment.  
 
8.2 Control of materials  
 
8.2.1  The manufacturer of the tank shall maintain a system of identification for the material used in 
the fabrication so that all material for pressure -retaining parts and non -pressure -retaining parts directly 
welded  to pressure -retaining parts in the completed work can be traced to origin. The system shall 
incorporate appropriate procedures for verifying the identity of material received from the supplier.  
 
8.2.2  Verifying procedures shall be based on the material ma nufacturer’s certificates and/or 
acceptance tests.  The system shall ensure that before cutting and forming parts of the tank, the 
original identification mark of the material is transferred to any parts of the tank that could be without 
markings after the  process.  The manufacturer shall ensure the material conforms to the design and/or 
drawing specification.  
 
8.2.3  In laying out and cutting the material:  
 
a) The material identification mark shall be clearly visible when the pressure part is complete; or  
b) The manufacturer shall operate a documented system that ensures material traceability for all 
materials in the completed tanks.  
 
8.2.4  If the materials identification mark is unavoidably cut out during manufacture of a pressure 
part, it shall be transfer red by the pressure part manufacturer to another part of the component. 
Transfer of the mark shall be carried out by a person designated by the manufacturer.  
 
8.2.5   When identification on materials is transferred, the method of marking shall not have any 
detrimental effect on the specified materials properties.  
 
8.2.6  Details of welding consumables shall be retained.  
 
8.3 Acceptable weld details  
 
8.3.1  The manufacturer, in selecting an appropriate weld detail, shall consider : DEAS 903: 2016  
© EAC 2016  – All rights reserved  7 
  
a) The method of manufacture;  
b) The se rvice condition;  
c) The ability to carry out necessary non -destructive testing.  
 
The root faces of welding preparations shall be aligned within the tolerances given in the welding 
procedure specification.  
 
NOTE  Examples of typical welded joints used on the  tank are given in Annex E . 
 
8.3.2  If a tank is made from more than one shell strake, the longitudinal weld of adjacent strakes 
shall be staggered by at least 100 mm between weld edges.  
 
8.3.3  Where the tank diameter is less than 1.5 m and no internal acce ss is provided, joggle joints 
are permitted for end to shell joints. Only dished ends shall be joggled.  
 
8.3.4  Joggles shall be sufficiently clear of the knuckle radius to ensure that the edge of the 
circumferential weld is at least 12 mm clear of the knuc kle. 
 
NOTE  A typical joggle joint detail is shown in Figure E.2  
 
8.4 Heat treatment and forming  
 
8.4.1  Cold forming  
 
8.4.1.1   Heat treatment of cold formed cylindrical shells is not required.  
 
8.4.1.2   Cold formed dished ends shall be heat  treated unless the manufa cturer can demonstrate that 
the properties of the finished products confirm to the original design.  
 
8.4.1.3   Cold formed dished ends that have not been heat treated shall not be welded or heated 
locally in the knuckle area to temperatures above 55 oC with out subsequent heat treatment.  
 
 
8.4.2  Hot forming  
 
8.4.2.1   For normalized steels, because of the danger of excessive grain growth, the work piece 
temperature during hot forming shall not exceed 1050 oC.  Before the final stage of hot forming, or if 
hot forming  is performed only once, the work piece shall not be heated above 980 oC. 
 
NOTE:  The duration of hot forming should be kept to a minimum to avoid grain growth.  
 
8.4.2.2  If no subsequent heat treatment is applied, hot forming shall be completed above 750 0 C, or 
above 700 0C if the degree of forming in the final stage does not exceed 5 %.  
 
8.4.2.3   Cooling shall be carried out in still air.  
 
8.4.2.4   If hot forming is carried out in conditions other than those specified in this sub clause, 
normalizing as sp ecified by the steel manufacturer or supplier shall be carried out after hot forming.  
 
8.4.2.5   A competent person shall specify the heat treatment procedure to ensure that the properties 
of the finished product conform to the original design.  
 
8.4.3  Testing of formed parts  
 DEAS 903: 2016  
8 © EAC  2016  – All rights reserved  
 8.4.3.1   For cold -formed parts not subject to heat treatment, no mechanical tests are required in 
respect of the forming operation.  
 
8.4.3.2   All other formed parts shall have tests carried out after the last forming operation or any heat 
treatment to demonstrate conformity to the material specification. Test pieces shall be taken from an 
excess length or a redundant piece of the formed part or from a separate test piece formed to same 
procedure. The test pieces shall consist of one tensile an d three impact specimens.  
 
8.4.3.3   In case of formed ends, the test pieces shall be taken from sample ends selected as follows:  
 
i)  From initial production: 1 from 10 of each family; and  
ii)  From production formed ends 1 formed part in 1 000 production  units, but not less than one per 2 
years.  
 
8.4.3.4   Ends with the following characteristics are considered to be a family of ends:  
 
i) same material specification;  
ii) same forming process;  
iii) same heat treatment;  
iv) geometrical similarity to ± 10 %.  
 
8.4.4  Visual examination and control of dimensions  
 
Outsourced  formed parts that require acceptance certificates shall be submitted by the tank 
manufacturer to visual  examination and dimensional check in the delivery condition and the results 
shall be included i n the tank acceptance certificate.  
 
8.4.5  Marking  
 
Formed parts of pressure tanks shall be marked so that the material and the manufacturer of the part 
can be identified as specified in 8.2. For batch testing the relationship to the batch shall be evident.  
 
8.5 Welding  
 
8.5.1  General  
 
Welding of the joints of the component parts of a tank shall be carried out only if all the following apply:  
 
i) a welding procedure specification is compiled by the manufacturer;  
 
ii) the welding procedures selected by the  manufac turer are qualified for the field of application. 
If the design is based on material specifications agreed by a competent authority, the welding 
procedure shall be qualified using material with the higher properties;  
 
iii) the welders and welding operators  are qualified for the work and their approval (8.5.5).  
 
8.5.2  Longitudinal welds  
 
There shall be not more than one longitudinal weld on any strake. Longitudinal welds shall be full 
penetration butt welds  
 
8.5.3  Welding procedure specification (WPS)  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  9 
 The m anufacturer shall compile a welding procedure specification for each joint or family of joints.  
 
8.5.4  Qualification of WPS  
 
8.5.4.1  Welding procedures shall be qualified by welding procedure tests.  
 
8.5.4.2  Production and testing of test pieces shall be  certified by an independent body.  
 
8.5.4.3  Welds shall be subjected to impact testing as specified in 10.2.4.5 . 
 
8.5.5  Qualification of welders and welding operators  
 
8.5.5.1  Welders and welding operators shall all be approved.  
 
8.5.5.2  Production and tes ting of test pieces shall be certified by an independent body.  
 
8.5.5.3  A list of welders and welding operators and records of approval tests shall be maintained by 
the manufacturer.  
 
8.5.6  Preparation of edges  
Preparation of edges shall be done in accorda nce with ISO 9692.  
 
Material may be cut to size and shape by any mechanical or thermal cutting process or by 
combination of these.  Cutting may be carried out before or after forming.  
 
The surface to be welded shall be cleaned of oxide scale, oil, grease, or other foreign substance that 
could have a detrimental effect on weld quality.  
 
Edges to be welded shall be kept in position, either by mechanical means or by tack welds or by a 
combination of these .  
 
Tack welds shall be removed or fused again in the we ld bead. The manufacturer shall ensure that tack 
welding does not generate metallurgical or homogeneity defects.  
 
The manufacturer shall ensure that for welds without a sealing run (single sided welds), the edges are 
sufficiently aligned and spaced to ensu re the required penetration at the weld root.  
 
NOTE  A joggle may be used on circumferential welds (8.3.3.) to act as an integral backing trip.  
 
8.5.7  Attachments of fastenings  
 
Welding of attachments (temporary or otherwise), including supports, to a pres sure retaining part shall 
follow a qualified procedure.  
 
Temporary attachments shall be removed by a technique that does not affect the properties of the 
metal or pressure part to which they are welded.  
 
Care shall be taken to ensure that the area of a rem oved attachment is free from surface cracks.  The 
area shall be dressed smooth and subjected to magnetic particle (10.4.4.) or penetrant (10.4.5) 
testing.  Any cracks detected shall be repaired as appropriate.  
 
8.5.8  Preheat  
 DEAS 903: 2016  
10 © EAC  2016  – All rights reserved  
 8.5.8.1  The manufacturer shall  include the preheating temperature in the WPS.  The preheating 
temperature shall depend on the composition of the metal to be welded, the weld process, and the arc 
energy.  
 
8.5.8.2  Welding shall not be carried out if the temperature of the parent metal ne ar the joint is less 
than + 5 oC. 
 
8.6 Post -weld heat treatment  
 
If required, post -weld heat treatment shall be carried out in accordance with Annex G.  
 
NOTE 1  Post-weld heat treatment is not required for the material types and weld thicknesses used on ta nks build in 
accordance with this Standard.  Post -weld heat treatment may be carried out on tanks by agreement between the purchaser 
and the manufacturer.  
 
NOTE 2  Tanks contain many fillet welds that cannot be tested.  Where residual stresses and pressure  plus dynamic stresses 
apply, there is a greater risk of crack initiation and crack growth.  Lowering the residual stresses with post -weld heat treatment 
lowers the risk of cracking.  
 
8.7 Manufacturing tolerances  
 
Tolerances on the tank shape shall conform  to Annex F.  
 
NOTE  Annex H gives a conservative method of measuring peaking (including ovality).  
 
8.8 Repairs to pressure envelope and direct attachment welds  
 
8.8.1  General requirements  
 
Imperfections shall be repaired by a mechanical or thermal process or comb ination of these.  
 
The thickness of the material, after repair is completed, shall be within the tolerances of the design 
and not less than the minimum thickness specified in Clause 5.  After the repair, the material shall be 
subjected to the non -destructi ve testing originally applied.  
 
For welding repairs, after any specified post -weld heat treatment has been carried out, the repaired 
vessel shall be subjected to further post -weld heat treatment in accordance with the original 
specification.  
 
8.8.2  Repair of sur face imperfections in the parent metal  
 
8.8.2.1  Minor surface imperfections (arc strikes, tool marks, cutting marks etc.) shall be removed by 
grinding.  
 
8.8.2.2  The ground -out area shall have a smooth transition into the surrounding areas.  
 
8.8.2.3   Repair s that involve depositing of a weld metal shall be carried out in accordance with a 
qualified welding procedure.   
 
8.8.3  Repair of weld imperfections  
 
8.8.3.1   The extent of repairs of weld imperfections shall be determined by the position, size and type 
of def ect. Repairs may cover only the defect and surrounding area or may involve complete removal of 
the weld containing the defect.  Repairs by grinding or other processes involving removal of material 
and that do not include welding shall be finished with a sm ooth transition into the surrounding areas.  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  11 
 8.8.3.2   Thermal gouging shall be carried out using an electrode that minimizes contamination of 
remaining material surfaces.  
 
8.8.3.3   Repairs shall be carried out in accordance with a qualified welding procedu re and the 
welders shall be qualified.  
 
9 Construction and workmanship of internal pipe work  
 
Welding of internal pipe work shall be to the same quality as for the pressure retaining parts.  
 
10 Inspection and testing  
 
10.1 General  
 
All tests shall be carri ed out after any heat treatment process and prior to any external corrosion 
protection and finishing.  
 
10.2 Mechanical testing  
 
10.2.1  Production test plates  
 
To control the continuing quality of welded joints and to ensure their mechanical properties conf orm to 
the specification, production test plates shall be welded and tested.  
 
10.2.2  Longitudinal welds  
 
10.2.2.1   For tanks that include one or more longitudinal welds, the test plates, if practicable, shall be 
attached to the shell plate on one end of th e weld so that the edges to be welded in the test plate are a 
continuation and duplication of the longitudinal weld.  
 
10.2.2.2   The weld metal shall be deposited in the test plates continuously with the welding of the 
corresponding longitudinal weld, so th at the welding process, procedure and technique are the same.  
One test plate shall be produced per tank.  
 
10.2.3  Circumferential welds  
 
If circumferential welds are welded by a different procedure to the longitudinal weld, the manufacturer 
shall produce t wo further test plates per year or one test plate per tank, whichever is the fewer.  
 
Test plates shall be produced by the same procedure as used in construction of the tank.  
 
10.2.4  Mechanical tests  
 
Each production test plate shall be tested on specimens as required by Annex I.  
 
10.2. 4.1 Test requirements  
 
The test specimens shall be prepared and tested as follows:  
 
10.2. 4.2 Bend test  
 
Bend testing and test requirements shall be carried out.  
 
10.2. 4.3 Tensile test  DEAS 903: 2016  
12 © EAC  2016  – All rights reserved  
 Test shall be carried out in accordance wi th ISO 6892 -1. The tensile strength of the test specimen 
shall be not less than the corresponding specified minimum value used for the design.  
 
10.2. 4.4 Macro -examination  
 
Macro -examinations shall be carried out and shall show sound build -up of weld beads and sound 
penetration.  
 
10.2. 4.5 Impact tests  
 
10.2. 4.5.1 Tests shall be carried out in accordance with ISO 148 -1 with a V -shaped notch 
perpendicular to the surface of the test specimen.  
 
10.2. 4.5.2  Impact -strength tests are not required on welds with a p arent plate thickness less than 5 
mm. 
 
10.2. 4.5.3  For plates below 10 mm but not less than 5 mm thick, test specimens with a cross section 
of 10 mm wide by the thickness of the parent plate shall be used.  
 
NOTE  Machining to either 7.5 mm or 5 mm may be pe rmitted if required.  
 
10.2. 4.5.4  If the thickness of the parent plate is ≤ 10 mm, tests shall be carried out on three test 
specimens with the notch at the centre of the weld and three test specimens with the notch at the 
centre of the heat affected zone ( with the V -notch crossing the fusion boundary at the centre of the 
specimen).  
 
10.2. 4.5.5  If the thickness of the parent plate is > 10 mm, tests shall be carried out on three test 
specimens from the centre of the weld and three test specimens from the hea t affected zone (with the 
V-notch crossing the fusion boundary at the centre of the specimen).  
 
10.2. 4.5.6  The average value obtained from each set of three test specimens shall be not less than 
34 J/cm2. Not more than one of the individual values shall b e below 34 J/cm2 and shall, in no case be 
less than 24 J/cm2. This shall apply to specimens taken at the centre of the weld and in the heat -
affected zone.  
 
10.2. 4.5.7  The normal test temperature shall be -20 oC but for tanks that may be subjected to 
tempe ratures below -20 oC, as defined in 4.1, impact testing shall be carried out at a temperature of  
-40 oC. 
 
 
10.2. 4.6 Retests  
 
10.2. 4.6.1  Production factors can result in a scatter of mechanical test results that occasionally fall 
below the agreed specific ation level.  If the results of tests do not conform to 10.2.4.1  to 10.2.4.5 , the 
following re -tests shall be carried out:  
 
a)  Two tensile tests;  
 
b) Two bend tests;  
 
c)  One impact test (with three specimens).  
 
10.2. 4.6.2  In a repeated impact test, on t he weld deposit or the heat affected zone, none of the 
individual values shall be below 34 J/cm2.  The average value of all results of the original test and the DEAS 903: 2016  
© EAC 2016  – All rights reserved  13 
 retests shall be a minimum of 34 J/cm2.  If the retests fail these requirements then the welds 
represented by the test specimens shall be deemed not to conform to this Standard.  
 
10.2.4.7  Record of test results  
 
A test record shall be prepared indicating conformity of the test results to the specified requirements.  
 
10.3 Non-destructive testing  
 
 
10.3.1 Internal imperfections  
 
Examination for internal flaws shall comprise 100 % radiographic and/or ultrasonic examination of 
shell longitudinal and circumferential welds in accordance with 10.4.1 and 10.4.2 or 10.4.3 as 
applicable.  
 
10.3.2  Surface imperf ections  
 
Examination for surface imperfections shall comprise 100 % magnetic particle and/or penetrant testing 
of all welds that attach nozzles, branches and doubler plates to the shell and end plates and all other 
attachment welds to pressure components i n accordance with 10.4.4 and 10.4.5 as applicable.  
 
10.4 Non-destructive testing techniques for welds  
 
10.4.1  Visual examination of welds  
 
All welds shall be visually examined on completion. The examined surface shall be well 
illuminated and free from grea se, dirt, scale, residue, or protective coating of any kind. The 
examination shall apply to both sides of the welded joint as far as possible.  
 
10.4. 2 Radiographic techniques  
 
Radiographic examinations shall be carried out in accordance with  ISO 17636 -2.  
 
NOTE  Other radiographic techniques may be used by agreement between the purchaser, the manufacturer and the 
competent person, provided it can be demonstrated that comparable sensitivities can be achieved.  
 
10.4. 3 Marking and identification of radiographs  
Each section of weld shall have suitable symbols affixed to identify the following:  
 
a) The job or workplace serial number, order number or similar distinctive reference number;  
 
b) The weld location;  
 
c) The section of the weld;  
 
d) Arrows or other symbo ls, alongside but clear of the outer edges of the weld to clearly identify the 
position.  
 
NOTE  The weld location reference may be identified e.g. with a letter “L” for a longitudinal weld and a “C” for a 
circumferential weld, with addition of 1, 2, 3 etc, to indicate whether the weld was the first, second, third, etc, of the type.  
 
10.4. 3.1 Symbols consisting of lead arrows, letters and/or numerals shall be positioned so that their 
images appear on the radiograph of the section.  
 DEAS 903: 2016  
14 © EAC  2016  – All rights reserved  
 10.4. 3.2 Sufficient overlap  shall be provided to ensure that radiographs cover the whole of the weld.  
Each radiograph shall exhibit a number near each end.  
 
10.4. 3.3  Radiographs of repair welds shall be clearly identified R1, R2, etc., for the first repair, second repair, 
etc. 
 
10.4.4 Ultrasonic techniques  
 
Ultrasonic examination shall be carried out.  
 
10.4. 5 Magnetic particle techniques  
 
Magnetic particle inspection techniques shall be carried out.  
 
Particular care shall be taken to avoid damage to surfaces by misuse of magnetic e quipment. Any 
damage that occurs shall be repaired.  
 
10.4.5  Penetrant techniques  
 
Dye or fluorescent penetrant examination of welds shall be carried out.  
 
NOTE  Guidance on the selection of non -destructive test methods for welds is given in Annex J.  
 
10.5 Qualification of non -destructive testing personnel  
 
Personnel performing and evaluating non -destructive examinations shall be qualified and certified in 
accordance with ISO 11484. Non -destructive testing personnel and supervisors shall have adequate 
knowled ge of the job and basic knowledge of welding. Testing personnel shall be independent of the 
personnel responsible for manufacture.  
 
 
10.7 Acceptance test criteria  
 
Acceptance criteria for non -destructive and visual examinations shall conform to Annex I.  
Unacceptable imperfections shall be repaired in accordance with 8.8 or the component shall be 
rejected. Imperfections shall be as defined in ISO 6520 -1 and ISO 6520 -2. 
 
10.8 Pressure test  
 
10.8.1   On completion of construction, tanks shall be subjected to a  hydraulic pressure test at a test 
pressure of 1 .3 times the design pressure specified in Annex D.  
 
10.8.2   The general membrane stress occurring at the actual test pressure shall not exceed 90 % of 
the specified minimum yield stress of the material.  
 
10.8.3  The test pressure required by this standard is higher than the minimum test pressure 
specified in other pressure vessel manufacturing standards. This higher test pressure shall not be 
used to allow marking of the tank for other substances or LPG mixtur es than those used as a basis for 
the design.  
 
10.8.4   The first pressurization shall be carried out under controlled conditions with appropriate 
safety precautions.  
 
NOTE  A recommended procedure is given in Annex K.  
 
10.9 Capacity  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  15 
 Following the pressure test the water capacity of each tank shall be checked by suitable method to an 
accuracy of at least 1 % and recorded.  The capacity shall be corrected to 20 oC. 
 
11 External corrosion protection and finishing  
 
11.1 External protection  
 
Tanks shall have suf ficient external protection against corrosion arising from atmospheric effects.  
 
11.2 Finishing operations  
 
The tank shall be protected from the ingress of foreign matter during transportation, handling and 
fixing to the chassis, and other finishing operat ions.  
 
12 Marking  
 
As a minimum, markings conforming to Annex L shall be permanently placed on a nameplate 
permanently attached to the tank or supports.  
 
13 Records and documentation  
 
13.1 Documentation obtained by the manufacturer  
 
The following documenta tion shall be obtained by the manufacturer:  
 
a) Certificates showing chemical analysis and details of the mechanical properties of the steel used 
in construction of the pressure retaining parts of the tanks (see 4.6);   
 
b) A certificate for formed parts (s ee 8.4.4) ;and 
 
c)  acceptance certificate for outsourced parts.  
 
13.2 Records prepared by the manufacturer  
 
The manufacturer shall prepare the following records:  
 
a) Fully dimensioned drawings including material specification and design criteria;  
 
b) Recor ds of heat treatment, if applicable;  
 
c) Records of mechanical tests;  
 
d) Records of visual examination and dimensional checks on formed parts;  
 
e) Welding procedure specifications and qualification certificates  
 
f) A list of the welders and records of th eir approval tests  
 
g) Records of any weld repairs;  
 
h) A certificate of the hydraulic pressure test;  
 
i) Radiographs and results of non -destructive tests;  
 DEAS 903: 2016  
16 © EAC  2016  – All rights reserved  
 j) A certificate of water capacity measurement;  and 
 
k) A certificate of conformity to this standa rd, endorsed by a notified/designated body.  
 
13.3 Retention and supply of documents  
 
The manufacturer or agent shall retain copies of all documentation in accordance with the relevant 
national legislations  of the Partner States . Documentation shall be supp lied to the purchaser or 
operator on request.  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  17 
 Annex  A  
(normative)  
 
Guidance on selection of material grades  
 
A.1 This Annex lists material grades from the standards specified in Clause 4 that may be used for 
fabricating the tank.  
 
NOTE  Not all of the gr ades listed have guaranteed mechanical properties that conform to Clause 4.  Some grades may 
require special testing to demonstrate conformity.  
 
The steel group is listed for each of the grades or equivalent.  The grouping shall be in accordance 
with ISO 9 328-2. 
 
 
 
 
 
 DEAS 903: 2016  
18 © EAC  2016  – All rights reserved  
 Annex B  
(normative)  
 
Reference temperatures for design  
 
B.1 Introduction  
 
The liquid volume and developed pressure of LPG in a closed system are a function of the ambient 
temperature.  
 
B.2 General  
. 
 
The reference temperatures designated in t his Annex shall be applicable for the design of all road 
tankers operating within the jurisdiction of the EAC Partner States , unless the competent authority 
under special consideration and permit given in writing, authorizes for transport designated type of LP 
Gas, the reference temperature designated in Annex C.  
 
B.3 Developed pressure  
 
The reference temperature for developed pressure shall be as specified in Table B.1. The developed 
pressure shall be the pressure of commercial propane at the reference te mperature. The 
corresponding pressure value shall be not less than the minimum test pressure specified in KS 
CD/K/1;2016 . 
 
Table B.1 — Reference temperature for developed pressure  
 
Sun shield  Tank diameter  
m 1.5 D
 
oC Tank diameter  
D < 1.5 m
  
oC 
Without sun shield  65 
 70 
With sun shield  65  
 70 
 
B.4 Filling  
 
The reference temperature used for calculation of maximum allowable fill shall be 55 o C. 
 
Tanks shall be designed to be filled in accordance with the following for mula:  
 
Degree of filling (kg/L) = 0.95 x density of the liquid phase at the reference temperature (55 oC). 
 
Tanks shall not become 100 % liquid full at 60 oC. DEAS 903: 2016  
© EAC 2016  – All rights reserved  19 
 Annex C  
(informative)  
 
Alternative reference temperatures for design  
 
C.1 Introduction  
 
The liqu id volume and developed pressure of LPG in a closed system are a function of the ambient 
temperature.  
 
C.2 General  
 
The reference temperatures designated in this Annex shall be applicable for the design of road 
tankers when authorized by a competent author ity for use within specified terms that are given in 
writing.  
 
C.3 Developed pressure  
 
The reference temperature for developed pressure shall be as specified in Table C.1.  
 
Table C.1 — Reference temperatures for developed pressure  
 
Sun shield  Tank diameter  
D ≥ 1.5 m 
oC Tank diameter  
D < 1.5 m
  
oC 
Without sun shield  50 55 
 
With sun shield  50a) 55a) 
 
a) Lower values of temperature with a sun shield may be used if justified by 
experience or experimental testing.  
 
 
C.4 Filling  
 
The refe rence temperature used for calculation of maximum allowable fill shall be 32.5 oC. 
 
Tanks shall be designed to be filled in accordance with the following formula:  
 
Degree of filling (kg/l) = 0.95 x density of the liquid phase at the reference temperature ( 32.5 oC). 
 
Tanks shall not become 100 % liquid full at 40 oC. 
 
 
 
 
 
 DEAS 903: 2016  
20 © EAC  2016  – All rights reserved  
 Annex D  
(normative)  
 
Design  
 
D.1 Design stresses  
 
The nominal design stress f shall be the lesser of 
2.4R and 5.1m eHR  where:  
 
eHR
 is the yield strength specified in the material standard or specification;  
 
mR
 is the tensile strength specified in the material standard or specification  
 
The following units shall be used in the formulae in this Annex:  
 
— Pressure and stress – N/mm2 
 
— Dimensions - mm 
 
D.2 Design pressure  
 
D.2.1  Rigid single tankers and semi -trailers  
 
P = Pd      (D1) 
 
D.2.2  Tanker plus full trailer combinations  
 
P = Pd K     (D2) 
 
 
where,  
 
 p is the design pressure;  
 
 Pd is the highest developed gauge pressure for the products to be c arried, at the reference 
temperature given in Table B.1 or Table C.1;  
 
 K is the greater of 
  1.0;or  65/T-650.6  1r   
 
 Tr is the reference temperature for developed pressure given in Table B.1 or Table C.1.  
 
D.3 Design formula  
 
D.3.1  cylindrical shell calculation  
 
The minimum required thickness shall be the greater of:  
 
 
p 2fzpD  o
mine     (D3) DEAS 903: 2016  
© EAC 2016  – All rights reserved  21 
  
 and 
 
5.1500minoDe
     (D4) 
 
 where,  
 
Do is the outside diameter of the shell;  
 
P is the design pressure specified in D.2;  
 
z  is the joint efficiency = 0.85  
 
f  is the nominal design stress.  
 
D.3.2  Dished ends  
 
D.3.2.1  Minimum thickness  
 
Dished ends can be torispherical, ellipsoidal or hemispherical.  For tanker plus full trailer combinations, 
the following minimum thicknesses sh all apply;  
 
a) for tank diameter 
5.1D m, end thickness = 7 mm;  
 
b) for tank diameter D < 1.5 m,  end thickness = 6 mm.  
 
D.3.2.2  Torispherical end calculation  
 
The following rules are limited in application to ends for which:  
 
 
D r 06.0 i       (D.5)  
 
 r > 3e         (D.6)  
 
 
iD e 08.0        (D.7)  
 
 
oDR        (D.8)  
 
The required thickness e is the greatest of es, ey and eb, where:  
 
 
p fzpRes5.0 2       (D.9)  
 
 
 
fD R Cpei
y2.0 75.0       (D.10) 
 and DEAS 903: 2016  
22 © EAC  2016  – All rights reserved  
  
  
 






5.11
825,0
1112.0 75.0rD
fpD R ei
bi b    (D.11)  
 
 where,  
 
  
5.1eh bRf  for all materials  
 
 and 
 
 C or (β) factor determined from Figure D.1 or by calculation (see D.3.2.5);  
 
 
 Di inside diameter of end;  
 
 Do outside diameter of shell;  
 
 e required thickness of the end;  
 
 eb minimum thickness of knuckle to avoid buckling;  
 
 es  minimum thickness of end to l imit membrane stress in central part;  
 
 ey minimum thickness of knuckle to avoid axisymetric yielding;  
 
 f nominal design stress;  
 
 fo design stress for buckling calculation;  
 
 p design pressure;  
 
 R inside radius of curvature of central part of torispheri cal end;  
 
 r inside radius of knuckle;  
 
 z joint efficiency = 0.85  
 
The thickness of the spherical part of the end may be reduced to the value e s over a circular area that 
shall not come closer to the knuckle than the distance 
Re  
 
Any s traight cylindrical flange shall conform to D.3.1 for a cylinder, unless the length is not greater 
than
eDi2,0 , in which case the flange may be the same thickness as the knuckle.  
 
D.3.2.3  Ellipsoidal end calculation  
 
An ellipsoidal end is de fined as able to produce a truly semi -ellipsoidal shape without distinct spherical 
knuckle radii.  
 
The design method converts these ends to equivalent torispheres that are calculated in accordance 
with D.3.2.2.  DEAS 903: 2016  
© EAC 2016  – All rights reserved  23 
  
NOTE  These rules apply only to ends for whic h 1,7 < K < 2.2 and z = 0.85.  
 
Ellipsoidal ends shall be designed as nominally equivalent torispherical ends with:  
 
  
 
iDKr 

 08.05.0                                                           (D12)  
 
 
 iD K R 02.0 44.0                                                (D13)  
 
where  
 
 
K  is the shape factor for an ellipsoidal end, and  
 
ih
is the inside height of the ellipsoidal end.  
 
K will be calculated as follows;  
i ih DK 2
 
 
D.3.2.4  Hemispherical ends  
 
The required th ickness of a hemispherical end is given by equation Clause D.14.  The thickness of the 
cylinder to which the end attaches shall be kept at or above the minimum determined by D.3.1 for the 
cylinder up to the tangent line.  
 
This method is valid for 
:16.0oDe  
 
p fzpRes5.0 2         (D14)  
 
D.3.2.5  Equations for calculating C  
 
 
 R;0.04e minY         (D15)   
 
Y1 logZ          (D16)  
 
iDrX          (D17)  
 


4902.61006.1
YN        (D18)  
 
For X = 0,2;  
 
 
   5.0;95.05.82 94.156.0.max2
2,0 Y Y C        (D19)  
 
For X = 0,1:  
 
 
 N Z Z Z C 837.0 2943.1 0383.1 1833.02 3
1,0        (D20)  DEAS 903: 2016  
24 © EAC  2016  – All rights reserved  
  
For X = 0,06:  
 
 
 N Z Z Z C 8873.1 2937.3 2124.2 3635.02 3
06,0        (D21)  
 
For 0.1 < X < 0.2:  
 
 
  2.0 1.0 1.0 2.010 C X CX C        (D22)  
 
For 0,06 < X < 0.1:  
 
 
  1.0 06.0 06.0 1.025 C X CX C       (D23)  
 
NOTE  The equati ons for C (β), given above, lead to an iterative calculation.  A computer procedure is recommended.  
 
 
 
 
Figure D.1 — Parameter β for torispherical end — Design  
 
 
D.3.3  Conical shell calculations  
 
D.3.3.1  General requirements  
 
This calculation is for offse t cones between two cylinders (see Figure D.2).  
 
The cylinders shall have parallel centre lines offset from each other by a distance not greater than the 
difference between their radii.  DEAS 903: 2016  
© EAC 2016  – All rights reserved  25 
  
A thickness shall be calculated in accordance with D.3.3.3 for the ju nction at the large end.  
 
A thickness shall be calculated in accordance with D.3.3.4 for the junction at the small end.  
 
The greater of these shall apply to the whole cone.  
 
The calculations do not apply to cones for which the half angle at the apex of the  cone is greater than 
60o, or for which 
001.0 Da cos c e  where 
cD  is the mean diameter of the cylinder at the junction 
with the cone.  
 
D.3.3.2  Thickness of conical shell  
 
The minimum permissible thickness of a cone, at any point a long its length, shall be the greater of 
:  where,e and j se
 
 
 
axpfzpDei
cos1
2         (D.24)  
 
or 
 
axpfzpDee
cos1
2         (D.25)  
 
where;  
 
lD
 is the inside diameter of the cone at the point under consideration;  
 
eD
 is the outside diameter of the cone at the point under consideration’  
 
cD
 is the mean diameter of the cone at the section under consideration, generally at the large end;  
 
e
 is the required thickness o f the cone;  
 
f
 is the nominal design stress;  
 
p
 is the design pressure;  
 
z
 is the joint efficiency = 0.85;  
 
a
 is the greatest semi -angle of the cone at the apex in degrees.  
 
The thickness of the cone may be increased locally or generally to provide reinforcement at branches 
or openings or to carry non -pressure loads.  
 
D.3.3.3  Junction between large end of a cone and a cylinder without a knuckle  
 
This sub clause applies provi ded that the joint is a butt weld in which the inside and outside surfaces 
merge smoothly with the adjacent cone and cylinder without local reduction in thickness.  
 DEAS 903: 2016  
26 © EAC  2016  – All rights reserved  
 NOTE 1  The junction is the intersection of shell centre -lines 
  D.2b Figure see  
 
 
15.0
cos11tan
31

 xeD
jc       (D.26)  
 
 
fpDec
j2          (D.27)  
 
where:  
 
 
  is a factor defined above;  
 
 
je  is a required thickness at a junction at the large end of a cone;  
 
 
1e  is the re quired thickness of the cylinder at the junction;  
 
 
2e  is the required thickness at the cone at the junction.  
 
NOTE 2  Equations D.26 and D.27 are a trial and error calculation for
je .  The answer is acceptable if the value is not less 
than that assumed to calculate
 .  Figure D.3 gives
  directly as a function of 
fp  and 
.  
The minimum thickness 
1e  of the cylinder adjacen t to the junction is the greater of 
j j e  wheree and ce
 is the thickness calculated using equation (D.27), and 
ce  is the required 
thickness of the cylinder as specified in D.3.1.  
 
Thickness shall be maintained for a distance of at le ast 
14.1
l  from the junction along the cylinder, 
where 
1 1 eD lc  is the length along the cylinder.  
 
The minimum thickness, 
2e , of the cone adjacent to the junction is the greater of 
je and e , where 
e  is 
the thickness of the cone specified in D.3.3.2 and 
je  is the thickness calculated using equation 
(D.28).  
 
This thickness shall be maintained for a distance of at least 
  
24.1
l from the function along the cone  
where  
 
 cos2 2 eD lc
 
 
D.3.3.4  Junction between the small end of a cone and a cylinder  
 
This subclause applies provided the thicknesses conform to D.3.1 and D.3.3.2  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  27 
 The required thicknesses 
2e  for the cone are determined by applying the following procedure.  
 
 
Assume initial values of 
:2 1 e and e         
 
1 2eeS
     
      
 (D.28)  
 
5.0tan4.0
1  xeDc
H
 
      
 (D.29)  
 
If S< 1:  
 
 
 
 
 
 
21
cos2S SS 
        (D.30)  
 
If S ≥ 1:  
 
xSS
cos2112
         (D.31)  
 
NOTE  Equations D.28 and D.29 do not provide values for 
2  1 e and e  separately.  These may require adjustment relative 
to each other to suit the design.  If:  
 
 
HcDfzep22  
 
then 
2 1 e and e are acceptable, where 
H  is a factor defined in equation D.29. If:  
 
p >
HcDfze
22  
 
repeat with increased values of 
2 1 e and e .  The final derived thickness for 
2 1 e and e  shall be 
maintained for a distance 
2 1 l and l from the junction, respectively, where 
2l and l are determined in 
accordance with D.3.3.3.  
 
 
 
 
 DEAS 903: 2016  
28 © EAC  2016  – All rights reserved  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
a) Offset cone  
 
 
 
 
 
 
 
b)  Cone/cylinder intersection wi thout knuckle: large end  
 
 
 
 
 
 
 
 
c)  Cone/cylinder intersection: small end  
 
Figure D.2 — Conical shells  
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  29 
 
 
 
 Figure D.3 — Values of coefficient 
   for cone / cylinder without knuckle  
 
 
D.4 Nozzle reinforcement  
 
D.4.1  The design method specified in D.4. 2 to D.4.10 shall only apply to cylindrical shells and 
dished ends with circular or elliptical openings, with which the conditions specified in D.4.1 and D.4.2 
apply.  
 
The size of openings shall be limited as follows:  
 
—cylindrical shells:  
;1i iDd  
 
—dished ends:   
.6.0 2im ird  
 
where,  
 
id
 is the inside diameter of the opening or branch;  
 
imr
 is the inside radius of the main body (shell or dished end).  
 DEAS 903: 2016  
30 © EAC  2016  – All rights reserved  
 The ratio of branch thickness to main body thickness 
m bee shall conform to the limits of Figure D.4.  
 
D.4.2  The distance between openings or branches, measured from the outside of the branches or 
pads, shall be not less than
ml2 , where:  
 
 
m m im m ee r l 2                    (D32)  
where:  
for shells 
2i imD r        (D.33)  
 
for torispherical ends 
ih imr r       (D.34)  
 
and for ellipsoidal ends 



  02.022.0
ii
i imhDD r    (D.35)  
 
where:  
 
iD
 is the inside diameter of shell  or straight flange of dished end;  
 
me
 is the analysis thickness of main body (shell or dished end) maintained within the length 
:ml
 
 
ih
 is the inside height of an ellipsoidal dished end;  
 
ml
 is the length of main body considered as effective compensation, measured along the 
material centerline from the edge of the opening without a branch or outside of the branch (or 
pad) see equation D.32);  
 
imr
 is the inside  radius of main body (shell or dished end) as specified in D.4.2;  
 
ihr
 is the inside radius of hemispherical dished end or spherical portion of torispherical head.  
 
D.4.3  Openings and branches and their reinforcements in dished heads sha ll be located entirely 
within the spherical portion of the torisphere.  
 
D.4.4  Cylindrical shells and dished ends with openings shall be reinforced where required.  
Reinforcement of the main body may be obtained by the following measures:  
 
a) by set -in weld ed pads (see Figure D.5a);  
 
b) by set -on or set -in welded branches as shown in Figure D.5b).  
 
D.4.5  The reinforcement area of the main body with openings cannot be calculated directly but 
shall be assumed in the first instance.  The assumption may be verif ied by means of the method given 
in D.4.6 to D.4.10.The applied method is based on basic pressure thicknesses derived from equation 
D.3 for cylindrical shells and from the equations in D.3.2 for dished ends, and leads to relationships DEAS 903: 2016  
© EAC 2016  – All rights reserved  31 
 between a pressure lo aded area 
A and a stress loaded cross sectional area that is given by 
fb fp fm A A A
 (see Figure D.5).  The calculation may be repeated using a corrected assumption of 
the reinforcement area.  
 
D.4.6  Where required sufficient rei nforcement shall be provided in all planes through the axis of the 
opening branch.  
 
D.4.7  For elliptical openings the ratio between the major and the minor axis shall not exceed 1.5.  
For elliptical openings in cylindrical shells and dished ends, the openi ng axis parallel to the longitudinal 
axis of the cylinder shall be considered as the diameter for design purposes.  For elliptical openings in 
dished ends the major axis shall be considered as the diameter.  
 
D.4.8  Set-on or set -in welded branches, fillet w elded only, may be considered as reinforcement if 
they conform to Figure D.5.  Each fillet shall have a throat thickness not less than 0.7 times the tank 
wall thickness.  
 
D.4.9  Reinforcement of openings by compensating plates shall not be permitted.  
 
D.4.1 0 All openings shall conform to the following general relationship:  
 
 
 
   fbb fpp fm fp fb fm p Af Af fA A A A Ap 5.0   (D36)  
 
where:  
 
p
 is the design pressure;  
 
pA
 is the pressure loaded area as shown in Figure D.5, calculated using intern al dimensions;  
 
fbA
 is the cross -sectional area of branch within the compensation limits;  
 
fmA
 is the cross -sectional area of main body (shell or head) within the compensation limits;  
 
fpA
 is the cro ss-sectional area of pad within the compensation limits;  
 
f
 is the nominal design stress of either the shell or dished end;  
 
bf
 is the lower of the nominal design stress of the branch and f;  
 
pf
 is the lower of the nominal design stress of the pad and f.  
 
NOTE  Simplified formulae for calculation of 
fb  , A and fp fmAA for various geometries are given in Figure D.5.  These 
formulae give acceptable results within the accuracy of the method.  Howev er, the designer can choose to calculate more 
precise values, based on the true geometry, if required.  
 
D.5 Nozzle reinforcement by pads or flanges  
 
Only pads of the set -in welded type conforming to Figure D.5a) shall be used.  DEAS 903: 2016  
32 © EAC  2016  – All rights reserved  
  
The width of the pads 
pl considered as contributing to the reinforcement shall not exceed 
.ml  
 
The value of 
pe used in determination of 
fpA in equation in D.4.10 shall not exceed 
.2me  
 
pl
 is the maximum length of pad considered to be effective as compensation, measured from the 
inside  surface of the main body;  
 
ml
 is as defined in equation D.32;  
 
pe
 is the thickness of pad;  
 
me
 is the actual thickness of main body (shell or head), minus any thinning allowance.  
 
D.6 Nozzle reinforcement by branches  
 
D.6.1  The wall thickness of branches (nozzles) shall, if required, exceed the thickness calculated to 
withstand intern al pressure for a length 
oh measured from the exterior wall of the main body.  
D.6.2  Areas 
fp fb fm, , A and A A pA shall be determined in accordance with Figure D.5b, where the 
lengths contributing to the reinforcement shall be not more tha n 
ml for the shell (see equation D.32), 
and: 
 
 
 
b b o b eed l        (D.37)  
 
for the branch.  
 
 
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  33 
  
Figure D.6 – Maximium branch to body thickness ratio  
 
 
The maximum value used in calculation of the part extending inside, it a ny, in the case of set -through 
branches (see Figure D.5b) shall be 
.5,0b bi l l  
 
 
bl
 is the length of external branch considered as effective compensation measured from the outside 
of  the main body.  
 
od
 is the outside diameter of branch;  
 
be
 is the analysis thickness of the branch maintained within the length 
bl  
 
 
 
 
 
 
 
 
 DEAS 903: 2016  
34 © EAC  2016  – All rights reserved  
 
 
 
 
 
 
 
 
 
 
a) Reinforcement by pads  
 
Figure D.5 — Design of openings:  Cylindrical shells with isolate d openings  
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  35 
  
 
 
 
 
 
 
 
 
b) Reinforcement by welded branches  
 
Figure D.5 (continued) — Design of openings: Cylindrical shells with isolated 
openings  
 DEAS 903: 2016  
36 © EAC  2016  – All rights reserved  
  
 
 
 
 
 
 
 
 
 
 
 
 
bi m b fbmm fmo
mim
p
l ee Ale AdlrA


2 2
 
 
 
c) Intruded branch in a dished end  
 
 
 
Figure D.5 (concluded) — Design of openings: Cylindrical shells with isolated 
openings  
 
 
 
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  37 
 Annex  E  
(informative)  
 
Example of joints  
 
 
 
 
 
 
NOTE 1:  The dimension limits (i.e.≥ e, ≤ 2,5e) apply to weld preparation only.  
 
NOTE 2:  The finished weld should have a smooth profile and  should completely fill the grooves to the full thickness of the 
plates being jointed. 8.3.3 specifies where joggle joints can be applied.  
 
 
Figure E.2 — Joggle Joint  
 
 
 
 
 DEAS 903: 2016  
38 © EAC  2016  – All rights reserved  
  
 
 
 
 
 
 
 
The offset section that forms the weld backing should be a close fit withi n the mating section round its 
entire circumference.  This can be achieved by machining the spigot of the offset section, provided the 
thickness remaining as backing material is not less than 75 % of the original thickness.  
 
3eL
 minimum but not less than 6 mm  
  
Figure E.3 — Nozzle joints: set on  
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  39 
 
 
Figure E.4 — Nozzle joints: set in  
 
 DEAS 903: 2016  
40 © EAC  2016  – All rights reserved  
 
 
 
                                                          Figure E.5 — Nozzle joints: integral backing  
 
 
 
 
 
 
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  41 
  
Annex F  
(normative)  
 
Allowable toler ances  
 
F.1 Tanks  
 
F.1.1  External diameter  
 
The mean external diameter derived from the circumference shall not deviate by more than 1.5 % from 
the external diameter shown on the manufacturer’s design drawing.  
 
F.1.2  Out of roundness  
 
Out of roundness, O, t he ratio of the difference between the maximum and minimum diameter and the 
mean diameter as defined by:  
 
 
min maxmin max2
D DD D

 
 
Shall not exceed 1.5 % of the specified external diameter, with a maximum (in millimeters) of:  
 

2001250D
 
 
 
These  tolerances shall apply to the shell, including the straight flange length on the dished ends.  
 
At nozzle positions, a greater out of roundness may be permitted if justified by calculation or strain 
gauge measurement.  Single dents or knuckles shall be wit hin tolerance.  Dents shall be smooth and 
their depth (i.e. the deviation from the surface of the shell) shall not exceed 1 % of their length or 2 % 
of their width.  Greater dents and knuckles are permissible if they are proven acceptable by calculation 
or strain gauge measurements.  
 
The cylindrical shell tolerance on tanks designed for vacuum conditions, where the thickness of the 
tank is governed by the vacuum criterion, shall be circular to within 0.5 % of radius (i.e. 0.005R) - 
measured from the true cen tre. 
 
F.1.3  Deviation of straightness  
 
The deviation from straightness shall not exceed 0.5 % of the total length of the tank.  
 
F.1.4  Irregularities in profile  
 
Irregularities in profile shall not exceed the following:  
 
— 2 % of the gauge length (checked b y a 20o gauge); or  
 
— 2.5 % of the gauge length (checked by a 20o gauge) where the length of the irregularities does not 
 exceed one quarter of the tangential length of the shell strake part between two circumferential 
 seams, with a maximum of 1.0 m; or  Figure E. 4 — Nozzle joints: set in 
 DEAS 903: 2016  
42 © EAC  2016  – All rights reserved  
  
— if either of the above are exceeded, proof by calculation or strain gauge measurement shall be 
 required to show that the stresses are permissible.  
 
If irregularity in the profile occurs at the welded seam and is associated with “flats” adjacent to the 
weld, the irregularity in profile or “peaking” shall not exceed 
3e  (see Figure F.1), where e is the wall 
thickness.  
 
NOTE 1  A conservative method of measurement (covering peaking and ovality) is given in Annex H.  
 
NOTE 2  Other types of g auges (e.g. bridge gauges, needle gauges) may be acceptable for measurements.  
 
F.2 Dished end tolerance  
 
F.2.1  Thickness of material  
 
The thickness of the material after forming shall at no point be less than the thickness determined in 
accordance with Ann ex D.  
 
F.2.2  Profile  
 
Dished ends shall be within the tolerances specified in Table F.1.  The crown radius shall be not 
greater than the value specified in the design, and the knuckle radius shall be not less than the value 
specified in the design.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  43 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Key  
 
R Crown radius  
 
r Knuckle radius  
 
H Dish height  
 
h Straight flange  
 
e Wall thickness  
 
D External diameter  
 
C Circumference 
D  
 
O Out of roundness (see F.1)  
 
i
 Deviation of t he bore from cylindrical shape:  inner side  
 
o
 Deviation of the bore from cylindrical shape:  outer side  
 
Figure F.1 — Example of a dished end profile  
 
 
 
 
 
 
 
 
 
 
 
 
Table F.1 — Dished end tolerances  
 
    DEAS 903: 2016  
44 © EAC  2016  – All rights reserved  
 Feature  Tolerance of the 
feature  Note s  
C D = 1 000 mm  ±0.4 %  Special manufacturing conditions may require smaller 
tolerances  D > 1 000 mm  ±0.3 %  
O 1 % of D  Special manufacturing conditions may require smaller 
tolerances  
H + 0.015 D or 10 mm 
whichever is the greater   
The tolerance shall  not fall below zero  
mm 10e
 – 0.3 mm  The actual wall thickness shall not fall below the 
minimum value calculated in Annex D  
e>10 mm  – 0.5 mm  
 

i  
5o For dished ends where the outer side angle is  
influenced by an upsetting due to the forming process, 
the deviation of the straight flange from the cylindrical 
shape shall be measured only on the inside of the 
dished end.   

o  
2o 
 
 
F.3 Assembly tolerances  
 
F.3.1  Middle line ali gnment  
 
F.3.1.1  For longitudinal joints in the cylindrical shells, the middle lines of adjacent plates shall be 
aligned within the following tolerances:  
 
— 1 mm for plate thickness e up to and including 10 mm;  
 
— 10 % of thickness for plate thickness e abo ve 10 mm.  
 
F.3.1.2  For circumferential joints, the middle lines of adjacent plates shall be in alignment with the 
following tolerances:  
 
— 1 mm for plate thickness e up to and including 10 mm;  
 
— 10 % of the thinner part + 1 mm for plate thickness e above 10 mm.  
 
F.3.2  Surface alignment  
 
The misalignment at the surface of the plates for plate thickness e shall either be as specified in a ) 
and b), or if this misalignment is exceeded, the surface shall be tapered with a slope of 1:4 over a 
width that include s the width of the weld, with the lower surfaces built up with added weld metal, if 
required, to provide the required taper.  Trimming of plate surfaces shall not be permitted if this 
reduces the thickness below the required minimum.  
 
a) For longitudinal j oints in shells the surfaces of adjacent plates shall be aligned within the following 
tolerances:  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  45 
  — 
4e  for thickness e up to and including 12 mm,  
 
— 3 mm for plate thickness e over 12 mm.  
 
b) For circumferential joints the surface of ad jacent plates shall be aligned within the following 
tolerances:  
 
 — 
4e  for plate thickness e up to and including 20 mm;  
 
— 5 mm for plate thickness e over 20 mm.  
 
F.4 Attachments, nozzles and fittings  
 
Pads, doubler plates, lugs, brackets , supports, and other attachments shall lift closely to the shell.  
The gap at all exposed edges to be welded shall not exceed 2 mm.  
 
Except where specific dimensions are shown on the fully dimensioned drawing, the maximum gap 
between the outside of any br anch or shell and the inside edge of the hole in the shell, flange, 
reinforcing ring, or backing ring shall not exceed 1.5 mm for openings up to 300 mm in diameter and 3 
mm for openings over 300 mm.  To achieve this gap it may be permissible to machine ove r a sufficient 
length of the outside diameter of the tank or nozzle to accommodate the attachment to be welded.  
The machined length shall not extend beyond the toes or edges of the attachment welds, and shall not 
reduce the nozzle wall thickness to a valu e less than the design thickness.  
 
F.5 Overall length  
 
The length of the finished tank shall conform to the nominal length shown on the manufacturing 
drawing (see 8.1).  
 
 
 
 
 
 DEAS 903: 2016  
46 © EAC  2016  – All rights reserved  
 Annex  G  
(normative)  
 
Heat treatment  
 
G.1 Method of post -weld heat treatment  
 
G.1.1 For post -weld heat treatment the tank shall be heated as a whole in an enclosed furnace 
within the limits of  550 oC to 600 oC and heldfor 30 min.  
 
 
G.1.2   Localized  post-weld heat treatment can be used to accomplish local heating of the weld 
using the  either of the following methods; Low/high voltage electric resistance heaters or combustion 
burners (high velocity gas, luminescent flame, infrared burners) or induction coil or quartz lamps. 
When conducting local post -weld heat treatment the following ar ea shall be considered see figure 
below;  
 
 
 
  DEAS 903: 2016  
© EAC 2016  – All rights reserved  47 
 
 
Nomenclature  
W = Widest width of weld.  
HAZ = Heat affected zone.  
SB = Soak band (width of the volume of the material where the holding temperature equals or exceeds the minimum and equals     
or is below the  maximum required. The minimum width is typically specified as W plus a multiple of t on each side of the weld).  
L = Minimum distance over which the temperature may drop to a percentage of that at the edge of the soak band.  
HB = Heated band (width of heat source).  
GCB = Gradient  control band (minimum width of insulation and/or gradient heat source).  
t = Nominal thickness.  
R = Inside radius.  DEAS 903: 2016  
48 © EAC  2016  – All rights reserved  
 Figure G.1 — Schematic diagram for description of local Circumferential 
heating.
  
 
 
Figure G. 3 —Minimum number of ther mocouples (monitoring & control) 
recommended for circumferential PWHT of a horizontal pipe butt weld for pipe 
greater than 12 NPS but less than or equal to 24 NPS (4 zones of control).  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  49 
  
 
 
Note: The soak band (SB)  is the volume of metal which should be hea ted to the minimum but not 
exceed the maximum required temperature. As a minimum, it should consist of the weld, HAZ, and a 
portion of the base metal adjacent to the weld being heated  
 
 The heated band (HB)  is the surface area over which the heat source is  applied to achieve the 
required temperature in the soak band and limit induced stresses in the vicinity of the weldment. It 
should consist of the soak band plus any adjacent base metal necessary to both control the 
temperature and limit induced stress wit hin the soak band.  
 
The gradient control band (GCB ) is the surface area over which insulation and/or supplementary 
heat source (s) are placed. It should encompass the soak band, heated band, and sufficient adjacent 
base metal such that the maximum permissi ble axial temperature gradient within the heated band is 
not exceeded.  
 
G.2 Temperature control   
 
During heating and cooling periods, variation in temperature throughout the tank or component shall 
not exceed 150 oC within 4 500 mm and the temperature grad ient shall be gradual.  Above 500 oC the 
variation shall not exceed 100 oC. 
 
During the heating and holding periods, the furnace atmosphere shall be controlled to avoid excessive 
oxidization of the surface of the tank or component.  
 
G.3 Temperature limit  
 
The temperature of the furnace when the tank is placed in or taken out shall not exceed 400 oC. 
 
The rate for heating or cooling the furnace temperature shall not exceed 220 oC/h. 
 
G.4 Temperature measurement  
 
The specified temperature shall be the actual temperature of any part of the tank or heated zone and 
shall be determined by thermocouples in effective contact with the tank.  
 
A sufficient number of temperatures shall be recorded continuously and automatically.  
 
Several thermocouples shall be applied t o ensure that the whole tank or treated zone is within the 
range specified.  Additional pyrometers shall be utilized to check that undesirable thermal gradients do 
not occur.  
 
The heat treatment record shall be available.  Thermocouples shall be calibrated  at regular intervals.  
 
 
 
 
 
 
 DEAS 903: 2016  
50 © EAC  2016  – All rights reserved  
 Annex  H  
(informative)  
 
Typical method for measurement of shell peaking  
 
H.1 Profile gauge  
 
To measure peaking a profile gauge (see Figure H.1) should be made for each size of tank.  
 
The minimum inner arc length of the gauge should be 0.175D o (20o of arc), where Do is the external 
diameter of the tank.  This diameter should be checked by measurement of the tank.  
 
NOTE  For some tanks the calculated arc length may not extend beyond the flats.  Because of this, the minimum arc le ngth 
of the gauge should be sufficient to clear the flats.  The width of the weld cut should be 28 mm but this may be longer to en sure 
that the cut out is clear of the weld (see Figure H.1).  
 
H.2 Peaking survey  
 
The approximate zone of maximum peaking shou ld be determined by taking readings at intervals of 
approximately 250 mm along the longitudinal welds.  When the maximum zone has been found, the 
maximum peaking P should be determined by accurate measurement of P 1 and P 2 (see Figure H.1).  
Care should be taken to ensure that the gauge makes contact with the shell at the points indicated in 
the note to Figure H.1.  
 
NOTE  It may be beneficial to make a taper gauge as shown in Figure H.2, for checking P 1 and P 2. 
 
Approximate dimensions of the flats should be m easured at the point of maximum peaking and 
recorded.  
 
If there is a significant high spot between points A and B or between points D and C in Figure H.1b) 
then this method may overestimate the peaking.  A plaster cast should be made to verify the amount 
of peaking.  Points A and D should be clear of any flats.  
 
 
 
 
 
 
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  51 
   
 
 
 
 
 
Key  
 
a)   20° gauge details P1 + P2  
 
b)   Measurement of outward peaking – maximum peaking, P = 4  
 
c)   Measurement of inward peaking  
 
NOTE       For Figure H.1 b) the gauge sh ould touch the shell at point A and as near to point B as possible.  When 
the gauge touches point D it should be as near as possible to point C.  
 
Figure H.1 — Measurement of shell peaking  
 
 DEAS 903: 2016  
52 © EAC  2016  – All rights reserved  
  
 
 
 
 
 
 
 
 
 
 
 
Figure H.2 — Taper gauge  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  53 
 Annex  l  
(normative)  
 
Welding imperfections and test specimens  
 
l.1 Imperfections  
 
Acceptance levels for internal and surface weld imperfections shall conform to Tables I.1  and I.2 
respectively, and the maximum reinforcement for welds shall conform to Table I.3.  
 
The following symbols are used in Tables I.1 to I.3:  
 
a nominal fillet weld throat thickness  
b width of weld reinforcement  
d diameter of pore  
h height of imperfecti on 
w width of imperfection  
l length of imperfection  
t wall or plate thickness  
 
Table I.1 — Acceptance levels for internal imperfections detected by NDT methods  
 
 
Imperfection  ISO 6520 -1 
 
ISO 6520 -2 
 
Reference  a) Limit for detectable imperfection  
Cracks an d lamellar tears  100 Not permitted.  
Porosity  2011  d = 0.3 t, maximum 4 mm.  
Uniformly distributed 
porosity  2012  For any individual gas pore, see 2011.  Not 
permitted if the total projected surface porosity 
exceeds 2 % of the considered projected 
surface of  weld.  
Localized (clustered) 
porosity.  2013  For any individual gas pore, see 2011.  Not 
permitted if the total projected surface porosity 
exceeds 4 % of the considered projected 
surface of the weld, which is the greatest of the 
following areasb. 
— area 1:  an envelope surrounding all the 
 pores;  
 
— area 2: a circle with a diameter 
 corresponding to the weld width.  
Linear porosity  2014  Same as for uniformly distributed pores, see 
2012, but the distance between two pores shall 
be greater than twice the diame ter of the larger 
pore, and not less than 4 mm, to ensure there 1 inner  edge of gauge to match the nominal outside diameter ( Do) of shell (to be checked)  DEAS 903: 2016  
54 © EAC  2016  – All rights reserved  
 is no lack of fusion.  
Elongated cavity  2015  l = 0,3 t, maximum 5 mm; and w = 2 mm.  Not 
permitted if occurring at a stop or restart.  
Wormhole  2016  Same as for elongated cavity, see 2015.  
 
Imperfection  ISO 6520 -1:1998  
ISO 6520 -2:1999  
reference  Limit for detectable imperfection  
Shrinkage cavity  202.00  l = 0,3 t, maximum 4 mm; and w = 2 mm.  Not 
permitted if occurring at a stop or restart.  
Slag and flux inclusions 
and oxide inclusions 
(parallel  to the weld axis)  301 
302 
303 Not permitted if occurring at a stop or restart.  
Slag and flux inclusions 
(random, not parallel to 
weld axis)  
 3012  
3013  
3022  
3023  Individual length, maximum 0,3t.  
Tungsten inclusions  3041  Same as porosity, see 2011.  
Coppe r inclusions  3042  Not permitted.  
Lack of fusion (side, root or 
inter-run) 401 Not permitted.  
Incomplete penetra tion 402 Not permitted  
a   the reference  numbers in column 2 are for imperfections as illustrated in the diagrams in the 
ISO 6520, parts 1 an d 2 
b area = maximum length of weld affected times local width of weld.  
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  55 
  
Table I.2 — Acceptance levels of surface imperfections in welds found by visual 
examination and/or NDT methods  
 
Imperfection  ISO 6520 -1:1998  
ISO 6520 -2:1999  
reference  Limit for det ectable imperfection  
Cracks and lamellar tears  100 Not permitted.  
Slag inclusions (all)  
Flux inclusions (all)  
Oxide inclusions (all)  
Metallic inclusions (all)  301 
302 
303 
304 Not permitted if occurring at the surface (shall be removed e.g. 
by grinding).  
Lack of fusion (side, root or 
inter-run) 401 Not permitted.  
Lack of penetration  402 Not permitted.  
Imperfect shape  
 500 These imperfections are normally accepted or rejected by 
visual examination and the same acceptance criteria shall be 
applied.  These  imperfections can occur on surfaces with not 
access for visual examination (e.g. internal tubes).  In these 
cases other techniques should be considered as a basis for 
acceptance.  
Undercut  5011  
5012  t ≥ 16 mm: h = 0.5 mm long imperfections.   
6 mm ≤ t < 16 mm: h = 0.3 mm for long imperfections;  
H = 0,5mm for short imperfections.  
t < 6 mm: h = 0.3 mm for short imperfections.  
Local protrusion  5041  Occasional local protrusion exceeding h (see 504) is permitted 
with a maximum that shall be related to the oper ating 
conditions.  
Shrinkage groove  5013  Long imperfections: not permitted.  
Short imperfections: h = 1 mm.  
Root concavity  515 A smooth transition is required.  
Excessive penetration  504 h = 1 mm + 0.6b , maximum 4 mm.  
Excessive convexity  503 h = 1 mm + 0. 15b, smooth transition required.  
Excess weld metal  502 h = 1 mm + 0.15b , smooth transition required.  
Excessive asymmetry of fillet 
weld 512 h = 2 mm + 0.15a . 
 
Imperfection  ISO 6520 -1:1998  
ISO 6520 -2:1999  
reference  Limit for detectable imperfection  
Irregular surface  514 
509 
511 
513 
517 Reinforcement shall be of continuous and regular shape with 
complete filling of groove.  
Overlap  506 Not permitted.  
Surface misalignment  507 See Annex F.  
Spatter  602 Normally, shall be removed from all pressure parts an d from 
both load carrying/attachment welds.  Isolated, non -systematic 
spatter may be permitted on components made from steel St. 
1 (see Table A.1).  DEAS 903: 2016  
56 © EAC  2016  – All rights reserved  
 Arc strike  
Spatter  
Tungsten spatter  
Torn surface  
Grinding mark  
Chipping mark  610 
602 
6021  
603 
604 
605 Grind smooth, accept subject to thickness and crack detection 
test. 
Under flushing  606 Not permitted, any local under flushing shall be related to the 
design characteristics (calculated thickness = minimum 
thickness for base material).  Thickness shall be mea sured by 
ultrasonic method in case of doubt.  
NOTE  Short imperfections: one or more imperfections of length not greater than 25 mm in any 100 mm length of weld, or a minimum of  
25% of the weld length for a weld shorter than 100 mm.  
 
Long imperfections: one  or more imperfections of total length greater than 25 mm in any 100 mm length of the weld, or a maximum of 25 % 
for a weld shorter than 100 mm.  
 
Table I.3 — Maximum reinforcement thickness for finished butt welds in plates  
 
Thicker plate thickness  
mm Maximum reinforcement 
thickness  
mm 
B ≤ 12 2.5 
B > 12  3 
 
The weld reinforcement shall be weld metal in excess of the quantity required to fill a joint as 
indicated in the figure below.  
. 
 
 
 
Figure I. 1 — Maximum reinforcement thickness for finished butt we lds in plates  
 
 
 
l.2 Test specimens  
 
Table I.4 gives the number of test specimens that shall be produced and tested from each test plate.  DEAS 903: 2016  
© EAC 2016  – All rights reserved  57 
  
Table I.4 —Test specimens  
 
Steel 
groupa Parent metal 
thickness e Face 
bend 
test Root 
bend 
test Macro -
examination  Impa ct 
test: weld 
deposit  Impact test: 
heat 
affected 
zone  Longitudinal 
weld tensile 
test Transverse 
tensile test  
St. 1 ≤ 12 1 1 1 3b 3b — — 
12 — — 1 3 3 — — 
St .2 ≤ 12 1 1 1 3b 3b — — 
12 — — — 3 3 1c 1 
NOTE  Non-destructive testing may be applied on the test plate prior to cutting the test specimens so that they are selected from sound  
areas.  
a The grouping system is  based on chemical analysis and material properties in relation to manufacture. The groupings are 
as defined and shall apply regardless of production form (i.e. plate, forging, piping, etc.).  Groupings for typical steels a re 
shown in Annex A.  The groupin gs shall be assessed on the guaranteed properties used in the design. The steel groupings 
are the groupings normally used in construction of road tanker tanks.  
 
b Not required for thicknesses less than 5 mm.  
c If difficulty is experienced in obtaining an a ll weld metal test, a full chemical analysis of the weld metal may be carried out.  
 DEAS 903: 2016  
58 © EAC  2016  – All rights reserved  
 Annex J  
(informative)  
 
Choice of non -destructive test methods for welds  
 
J.1 Internal imperfections  
 
Radiographic and ultrasonic methods both have advantages and disadvan tages in flaw detection, 
identification and sizing.  
 
Radiography is particularly suitable for detection and identification of “volume” imperfections such as 
cavities and solid inclusions and incomplete penetration where a gap exists.  Ultrasonic flaw detec tion 
is very suitable for detection and sizing of planar defects such as cracks, lack of fusion and “tight” 
incomplete penetration in ferritic steels.  
 
The two techniques should be regarded as complementary, and the most suitable method for the 
particular application and material should be chosen in each case.  Joint geometry may have an 
overriding influence on choice of method.  
 
If ultrasonic testing is used to determine the length of imperfections such as slag inclusions, sensitive 
techniques can result i n indications of length greatly in excess of indications that would be obtained by 
radiography.  
 
If ultrasonic testing is chosen, care shall be taken to limit the sensitivity to avoid detection of 
indications within the limits for acceptable imperfections (see Annex I).  
 
J.2 Surface imperfections  
 
Magnetic particle and penetrant testing indicate surface imperfections but do not indicate the depth of 
surface imperfections.  These tests should be used to ensure that no unacceptable surface 
imperfections are p resent.  Other suitable methods may also be required.  
 
 
 
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  59 
 Annex K  
(normative)  
 
Hydraulic pressure test  
 
K.1 Temporary fittings  
 
Temporary pipes and connections and blanking devices shall be designed to withstand the standard 
test pressure.  
 
Jointing mate rials for flanged joints shall be the same as used in service.  
 
K.2 Pressure gauges  
 
Pressure gauges shall be selected in accordance with EN 837 -2.  Pressure gauges shall have an 
accuracy at least equal to 4 % of the reading.  The test pressure of the tank  shall give a reading on the 
gauge between 50 % and 90 % of full scale deflection.  
 
NOTE  Alternative methods of pressure measurement (e.g. by transducer) may be used if they achieve equivalent accuracy.  
 
K.3 Pressurizing agent  
 
Water shall normally be used  as the pressuring agent.  Ensure that the tank is positioned so that 
entrapped air is vented.  
 
NOTE  To avoid risk of freezing, the temperature of the water during the test should be not less than 7 oC. 
 
K.4 Avoidance of shock  
 
Tanks undergoing pressure te sting shall not be subjected to any form of impact or pulsation loading.  
 
K.5 Applied pressure  
 
Gradually increase the pressure in the tank to test pressure which shall be maintained for not less 
than 30 min.  There shall be no signs of leakage or yield an d no pressure drop when the tank is 
isolated.  
 
On completion of the test, gradually release the pressure.  There shall be sufficient venting to ensure 
that no vacuum is created during draining.  
 
After the test the tank shall exhibit no sign of permanent di stortion.  
 
 
 
 
 DEAS 903: 2016  
60 © EAC  2016  – All rights reserved  
 Annex L  
(normative)  
 
Name plate  
 
Each tank shall be fitted with a corrosion -resistant metal plate conforming to Table L.1 permanently 
attached in a place readily accessible for inspection.  Markings on the plate shall be stamped or 
similar.  
 
To avoid any linguistic misunderstanding, the lines of the plates shall be numbered as shown in Table 
L.1. The minimum height of the letters shall be 3 mm.  The wording shall be in one of the official 
languages of the country of registration, and in Engl ish for international transport.  
 
The content of the name plate shall conform to Table L.2.  
 
Table L.1 — Name plate  
 
Design standard:  CD/K/5  
1 Manufacturer   
2 Approval number   
3 Manufacturer’s serial number   
4 Year of manufacture   
5 Test pressure  bar MPa 
6 Capacity of the tank (total)               litres  
   
   
7 Design pressure   
8 Design temperatures  max/min  oC  
9 Material tank   
10 Material protective lining/coating   
11 Insulation   
12 Maximum allowable working pressure   MPa 
13 Name(s) of dan gerous goods   
14 Maximum mass   
15 Stamps of expert (initial and periodic inspection)   
16 Stamps of expert (intermediate inspection)a  
a If required, otherwise shall be omitted.  
 
 DEAS 903: 2016  
© EAC 2016  – All rights reserved  61 
 Table L.2 — Content of name plate  
 
No Content  
1 Manufacturer’s name or  mark  
2 Approval number given by the competent authority or body designated by this authority  
3 Serial or production number issued by the manufacturer  
4 Year of manufacture  
5 Test pressure (gauge) in bar and/or Mpa.  The test pressure marked on the pla te shall not exceed the 
ADR test pressure for the mixtures authorized.  
6 Water capacity in litres  
7 ADR for tanks in accordance with Annex B, or country name(s) for tanks in accordance with Annex C.  
 Design pressure in bar and/or Mpa  
8 Design temperatu res in oC (if above 50 oC or below -20 oC) 
9 Materials of the shell and of the ends if different  
10 Material of protective lining or coating, if applicable.  Brand names may be used if they are in common 
use. 
11 Type of insulation of the tank in words, e .g. “vacuum” or “foam”, if applicable  
12 Maximum (allowable) working pressure (gauge) in bar and/or MPa  
13 Full names of the LPG mixtures approved for transport in the tank, as applicable.  These shall be the 
technical names used in scientific handbooks,  journals and texts.  Trade names shall not be used for this 
purpose  
14 Maximum allowable mass of substance given in non.13  
15 Month and year of the initial inspection and of each subsequent periodic inspection, and stamp of the 
expert who carried out th e inspection  
16 Month and year of intermediate inspection and stamp of the expert who carried out the test  
 
 DEAS 903: 2016    
 
© EAC 2016  – All rights reserved  
  
 Bibliography  
KS 203; Methods for radiographic X -ray examination of fusion butt welded steel  
KS 91, Specifications for liquefied petroleum gases (LPG)  
EN 287 -1, Approval and testing of welders — Fusion welding — Part 1: Steels  
EN 288 -2, Specification and approval of welding procedures for metallic materials — Part 2: Welding 
procedure —  Specification for arc welding  
EN 288 -3, Specification and app roval of welding procedures for metallic materials — Part 3: Welding 
procedure tests for the arc welding of steels  
EN 444, Non -destructive testing — General principles for radiographic examination of metallic 
materials by X -and gamma rays  
EN 462 -1, Non -destructive testing — Image quality of radiographs — Part 1: Image quality indicators 
(wire type) — Determination of image quality value  
EN 462 -,2, Non -destructive testing — Image quality of radiographs — Part 2: Image quality indicators 
(step/hole type)  — Determination of image quality value  
EN 473, Qualification and certification of NDT personnel — General principles  
EN 571 -1, Non -destructive testing — Penetrant testing — Part 1: General principles  
EN 729 -2, Quality requirements for welding — Fusion welding  of metallic materials — Part 2: 
Comprehensive quality requirements  
EN 837 -2, Pressure gauges — Part 2: Selection and installation recommendations for pressure 
gauges  
EN 875, Destructive tests on we lds in metallic materials —Impact tests — Test specimen location 
notch orientation and examination  
EN 876, Destructive tests on welds in metallic materials — Longitudinal tensile test on weld metal in 
fusion welded joints  
EN 895, Destructive tests on welds in metallic materials — Transverse tensile test  
EN 910, Destructive tests on welds in metallic materials — Bend tests  
EN 970, Non -destructive examination of fusion welds — Visual examination  
EN 1290, Non -destructive examination of welds — Magnetic particle  examination of welds  
EN 1321, Destructive tests on welds in metallic materials — Macroscopic and microscopic 
examination of welds  DEAS 903: 2016  
2 © EAC  2016  – All rights reserved  
  
EN 1418, Welding personnel — Approval testing of operators for fusion welding and resistance weld 
setters for fully mechaniz ed and automatic welding of metallic materials  
EN 1435 Non -destructive examination of welds — Radiographic examination of welded joints  
EN 1714, Non -destructive examination of welds — Ultrasonic examination of welded joints  
EN 10002 -1, Metallic materials — Tensile testing Part 1: Method test  
EN 10025, Hot -rolled products of non -alloyed structural steels — Technical delivery conditions  
EN 10028, (all parts).Flat products made of steels for pressure purposes  
EN 10045 -1, Metallic materials — Charpy impact tes t — Part 1: Test method.  
EN 10204, Metallic products — Types of inspection documents  
EN 12252 Equipping of liquefied petroleum gas (LPG) road tankers  
KS 06 -4, Specification for hot rolled steel sheets for the manufacture of low pressure gas cylinders  
KS 14 1-1ISO 6892 -1, Metallic materials -- Tensile testing -- Part 1: Method of test at room temperature  
Specification for tensile testing — Part 1: Steel in general  
EN 12493 , LPG equipment and accessories. Welded steel pressure vessels for LPG road tankers. 
Design and manufacture  
Recommended practices for local postweld heat treatment  by Joseph W. McEnerney  
ASME Section 8  
Guide for good industry practice for LPG road tanker management  - World LPG Association