TANZANIA DRAFT STANDARD  
MEDC 11(55 09) P3 -  Standard Specification for  Fuel Oil Meters of the 
Volumetric Positive Displacement Type  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
©TBS 2018                                                                                                                             1st Edition
 
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 Standard specification for  fuel oil meters of the volumetric positive 
displacement type  
 
0 Foreword  
 
Oil and natural gas have been utilized  by humankind for thousands of years. Recently in Tanzania 
discovery  of these resources is considered to have started . It is impossible to predict how long the 
petroleum age will last, but the projections above clearly  indicate that for next several decades fossil 
fuels will continue as the main source of energy for the world development . 
Due to growth of petroleum and service sector such as fuel oil supply in the country  lead to  high 
importation of different flow meas uring equipment such as fuel Oil Meters. In order to control the 
quality of these imported fuel oil meters  it is important to develop this standard . 
 
During the preparation of this draft Standard, assistance was derived from the following standard:  
ASTM F 1172 -88(2015)  – Standard Specification for Fuel Oil Meters of the Volumetric Positive 
Displacement Type  
 
 
1. Scope  
1.1 This specification provides the minimum requirements for th e design, fabrication, pressure rating, 
marking, and testing for fuel oil meters (volumetric positive displacement type).  
1.2 The following safety hazards caveat pertains only to the test method section of this specification. 
This standard does not  purport to address all of the safety conce rns, if any, associated with its 
use. It is the responsibility of the user of this standard to establish appropriate safety and health 
practices and determine the applicability of regulatory limitations prior to use.  
 
2. 0. Terminology   
Definitions of Terms Specific to This Standard:   
i) Fuel oil meter (volumetric positive displacement type)  — device intended to indicate the   
volume of liquid fuel oil delivered to a fuel distribution system over a period of time.   
ii) Maximum allowable working pressure (MAWP) — maximum system pressure to which a fuel 
oil meter may be subjected.  
 
3 Ordering Information   
Orders for products under this specification shall include the following applicable information:  
i) Title, number, and date of this specification.  
ii) Operating pressure (bars) and temperature (◦c ).  
iii) End connection and size.  
iv) Maximum capacity required.  
v) Type of fuel service.  
vi) Materials -external and internal.  
vii) Other test requirements .  
 
 
4 Materials and Manufacture   
4.1.1  Fuel oil meter casings, as well as any pressure -retaining parts, shall be constructed of ferrous 
material. All other parts shall be constructed of materials suitable for the service intended. 
Fasteners in contact with interior fluid shall be of corrosion -resistant steel.   
4.1.2  Seals and associated parts shall be of materials su itable for the service and the fl uid to be 
measured.   
4.2 Manufacture :  
  
Threaded fittings above two nominal pip e size (NPS) and socket welded fl anges above 3 NPS shall 
not be used in fuel oil meters with a MAWP above 1 N/mm2 and for service above 65º C.  
        
 
 
  
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 5 Other Requirements   
5.1 Components:   
 The meter shall consist of housing  with measuring mechanism and a register with counter 
mechanism.  
  
5.1.1  Measuring Chamber —the measuring chamber for all  meters shall be so constructed as not to 
show distortion under maximum allowable working pressure in any manner, or to affect the 
sensitivity of the meter.  
 
5.1.2  Adjusting Device —the meter shall be provided with an adjusting device for changing the 
registered quantity to attain desired calibration. The adjustment setting shall have provisions 
for locking and shall not change during the meter life except by manual readjustment. The 
adjusting device shall be non -cyclical and shall permit adjustment without disassembly of the 
mechanism except for removal of adjusting device cover plate. The plate shall be sealed by 
means of a lead seal. The meter shall be capable of c alibration adjustment over a minimum 
range of 5 %.  
 
5.1.3  Direction Marking of Meter  — Directions for positive and negative adjustment shall be 
permanently marked on the meter.  
  
5.1.4    Register —the register shall be of the direct -reading type. The register shall have a non -set 
back  total indicator and a setback -type run indicator, so that individual runs can be registered without 
affecting the total of all runs, as shown on the total indicator. The total indicator  shall have a minimum 
of eight fi gures, and the setback run ind icator shall have a minimum of five fi gures. Reset digits shall 
have a minimum height of 13 mm  and shall not be coated with fl uorescent paint. The indicating 
register shall read in 3.785 41 × 10−3 m3 each. The register shall be isolated from the fluid.  
  
5.1.5  Register Face —the register shall have a transparent, colorless plastic face of such size that 
all digits shall be easily read. Glass shall not be used.  
 
  
5.2 Rating, Design, and Fabrication:   
5.2.1  The maximum allowable working pressure -temperature rating (MAWP) for fuel oil meters 
conforming to this standard shall be established by at least one of the following  methods :  
 
5.2.2  If burst -type tests are used, it is not necessary to ruptu re the component.  Components that 
have been sub jected to a hydrostatic proof test shall not be offered for sale.   
 
Minimum Hydr ostatic test pressure = 1.3 x M AWP x LSR  
 
Where LSR is the smallest ratio of the allowable stress at test temperature to the allowable stress at 
design temperatures of materials (Bolting is excluded except when the calculated test pressure will 
exceed 90% of the bolt material minimum yield strength at the test temperature.)   
  
5.2.3  The water temperature shall not exceed 125◦F (52◦ C) during the test.  
 
5.2.4  Where welded construction is used for the fabrication of pressure containing parts, welded 
joint design details shall be full penetration welds extending through the entire thickness of 
the shell.  
 
5.2.5  Capacity —the maximum capacity of the meter shall be  as specifi ed by the manufacturer.   
5.2.6  Pressure Drop  — the maximum pressure drop between  the meter inlet and outlet shall not  
exceed 34 kPa .   
5.2.7  Error, Normal Flow  — for flow rate and calibration  setting between 5 and 100 % of maximum 
capacity, the error of the meter shall not exceed 0 .1 % for any one predetermined fl ow rate 
and accuracy setting.  
 
5.2.8  Maintainability  — the meter shall be so designed as not to require special tools for overhaul and 
repair.   
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 6.0 Workmanship, Finish, and Appearance   
6.1 Meter shall have all burrs or sharp edges removed and shall be cleaned of all loose metal chips 
and other foreign substances.   
6.2 Treatment and Painting —The exterior surface of the  meter shall be treated and painted in 
accordance with best commercial practi ce 
 
7. Number of Tests  
7.1. A representative fuel oil meter of each particular design shall be certified as having undergone 
the following qualification tests.   
  
7.2 Pressure Drop  — clean  fluid shall be pumped through the  meter at 100 % of manufacturers rated 
capacity. After the fl ow rate has been stabilized, the measured pressure drop between the inlet 
and outlet of th e meter shall not exceed 34 kPa .   
7.3 Production Tests:  
 
7.4 The manufacturer shall conduct  test each fuel oil meter by hydrostatic test methods as described 
in Section  8.  
  
7.5 Each meter shall be calibration tested at mid-range of fl ow capacity. The reading error shall not 
exceed 0.1 % at this fl ow rate.  
 
8. Test Methods   
8.1 Hydrostatic Test  — each  fuel oil meter shall be given a hyd rostatic shell test as follow .  
 
Minimum Hydrostatic test pressure = 1.3xMAWP x LSR  
 
Where LSR is the smallest ratio of the allowable stress at test temperature to the allowable stress at 
design temperatures of materials used. (Bolting is excluded except when the calculated test pressure 
will exceed 90% of the bolt material minimum yield strength at the test temperature.)  
  
8.2 The fluid tempera ture shall not exceed 125◦F (52◦ C) during the hydrost atic test, and the fluid used 
should be nonflammable. Further, it should not cause rusting and should otherwise be compatible 
with the internal parts of the fuel oil meter.  
  
8.3 The test arrangement shall be air free before pressurization.  
 
8.4 The minimum duration of the shell test shall be 30 s at required pressure.  
  
8.5 No visible leakage or structural damage shall show during the test.  
 
  
9. Inspection   
Each finished fuel oil meter shall be visually examined and dimensionally checked to ensure that the 
meter corresponds to this specification  
  
9.1 Nondestructive Examination of Welds :   
9.1.1  All welds shall be visually examined.  
   
9.2.2  Welded  inlet and outlet connections that are equal to or greater than 4 NPS or greater than 
0.375 -in. nominal wall thickness which are in services greater than 1 N/mm2 and 65ºC shall be 100 % 
radiographically examined.  
 
 
10. Certification  
 
10.1 All meters must be approved by relevant authority  before use . 
 
10.2 The pressure ratings established under this specification are based upon materials of high quality   
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 produced under regular control of chemical and physical properties by a recognized process. The 
manufacturer shal l be prepared to certify that his product has been so produced and that the 
physical and chemical properties thereof, as proven by test specimens and nondestructive 
testing or as documented by certifications from the producer or recognized distributor of t hese 
materials, are at least equal to the requirements of the appropriate specifications.  
  
10.3 When specified in the purchase order or contract, the manufacturer certification shall be 
furnished to the purchaser stating that samples representing each lot hav e been manufactured, 
tested, and inspected in accordance with this specification and the requirements have been met. 
When specified in the purchase order or contract, a report of the test results shall be furnished.  
 
 
11. Product Marking   
11.1 Each fuel oil meter shall be permanently marked with the following:  
  
11.2 Manufacturers name or trademark.  
  
11.3 Maximum allowable working pressure -temperature rating (MAWP).  
  
11.4 Flow Direction —the direction of flow through the meter shall be indicated by the words inlet and 
outlet, a directional arrow, or both, stamped or embossed on the meter.  
 
11.5 Size (end connection size), may be included at the option of the manufacturer.  
 
12. Quality Assurance Provisions   
The manufacturer of the fuel oil meter shall maintain the quality of the meters that are designed, 
tested, and marke d in accordance with this specifi cation. At no time shall a meter be sold that is 
marked with this standard d esignation that does not meet the requirements herein.