17398 Federal Register / Vol. 60, No. 65 / Wednesday, April 5, 1995 / Rules and Regulations

DEPARTMENT OF TRANSPORTATION

Research and Special Programs

Administration

49 CFR Parts 173, 178 and 180

[Docket No. HM–183C; Amdt. Nos. 173–240,

178–105 and 180–7]

RIN 2137–AC37

Cargo Tanks; Miscellaneous

Requirements; Revisions and

Response to Petitions for

Reconsideration

AGENCY: Research and Special Programs

Administration (RSPA), DOT.

ACTION: Final rule; response to petitions

for reconsideration.

SUMMARY: This document amends a final

rule published on November 3, 1994,

and concerns manufacture,

qualification, and maintenance of DOT

specification cargo tank motor vehicles.

In response to petitions for

reconsideration, RSPA is revising design

loading requirements for MC 331 cargo

tank motor vehicles and making other

minor editorial and technical changes

for clarity. The changes made in this

document are intended to ease certain

regulatory requirements where there

will be no adverse effect on safety.

DATES: Effective: May 22, 1995.

Compliance date: Compliance with

the regulations, as amended herein, is

authorized as of April 5, 1995.

FOR FURTHER INFORMATION CONTACT:

Ronald Kirkpatrick, telephone (202)

366–4545, Office of Hazardous Materials

Technology, or Jennifer Karim, (202)

366–4488, Office of Hazardous Materials

Standards, Research and Special

Programs Administration, U.S.

Department of Transportation,

Washington, DC 20590–0001.

SUPPLEMENTARY INFORMATION: On

November 3, 1994, RSPA published in

the Federal Register a final rule, under

Docket No. HM–183C (59 FR 55162),

amending certain requirements for the

manufacture, qualification and

maintenance of cargo tank motor

vehicles. Changes were made to relax

the requirements for structural integrity,

accident damage protection, welding

and design quality control procedures,

and pressure relief based on comments

from industry. Changes were also made

to require facilities repairing cargo tanks

stamped as meeting the American

Society of Mechanical Engineers Boiler

and Pressure Vessel Code (ASME Code)

to have a Certificate of Authorization for

use of an ‘‘R’’ stamp from the National

Board of Boiler and Pressure Vessel

Inspectors (National Board) Code .

RSPA received five petitions for

reconsideration of certain aspects of the

final rule. These petitions were

submitted by the Cargo Tank

Manufacturers Association (CTMA),

Cargo Tank Concepts, Ltd. (CTCL),

Truck Trailer Manufacturers

Association (TTMA), National Propane

Gas Association (NPGA), and the

Compressed Gas Association, Inc.

(CGA).

CTMA opposed several provisions

adopted in the final rule. First, CTMA

petitioned RSPA to reconsider its

position on how the design stress

calculations, in 49 CFR 178.345–3(c),

should be applied to cargo tank loading

conditions. Except for the loadings

prescribed in paragraph (c)(i), CTMA

stated:

[T]he loads are extreme loads that will be

experienced rarely if at all during the life of

a cargo tank and [the] ASME Code allowable

stresses should be based on the stress

increase allowed for wind and seismic loads

which are also experienced rarely if at all in

the life of stationary vessels. Per UG–23 of

the ASME Code, this increase is 20 percent.

CTMA believes that the loads specified in

building codes [are] applicable to pressure

vessels in the same manner. Using ASME

allowable stresses for these load conditions is

too conservative since margins of safety are

pyramided if rarely occurring extreme loads

cannot be resisted by emergency stresses as

recommended by CTMA.

As noted by RSPA in the preamble to

the final rule (59 FR 55165), discussions

have been ongoing for a number of years

on how to combine the loadings in

calculating the structural integrity

requirements. The concept of separating

structural loadings into two categories,

normal operating loading and extreme

dynamic loading, was proposed by

several cargo tank motor vehicle

designers at a public meeting in

February 1994 and more fully

developed later. In normal operations, a

cargo tank can be expected to routinely

experience relatively low dynamic

forces; these forces are to be considered

to occur simultaneously. Under extreme

dynamic loadings, the cargo tank

experiences relatively high forces which

occur rarely, if at all, during the life of

a cargo tank; these forces are considered

to act independently, one at a time. This

approach has received wide acceptance

and is the foundation for new

recommended practices under

development by a TTMA engineering

committee.

RSPA does not believe the

calculations for ‘‘stress increase’’

referred to by CTMA necessarily apply

to dynamic loads experienced either in

normal operations or in extreme loading

conditions experienced by cargo tank

motor vehicles. Two provisions for

increased allowable stresses are

prescribed in the ASME Code, Section

VIII, Division 1, UG–23. In paragraph (c)

of UG–23, a factor of 1.5 is discussed for

‘‘combined maximum primary

membrane stress plus primary bending

stress across the thickness.’’ Evidently,

the 20 percent factor referred to by

CTMA is associated with the factor

discussed in paragraph (d) for the

‘‘combination of earthquake loading, or

wind loading with other loadings in

UG–22,’’ with the stipulation that

earthquake and wind loadings need not

be considered to act simultaneously.

RSPA believes the many years of

experience accumulated by cargo tank

motor vehicle manufacturers support

the approach adopted in the final rule.

The reference in the CTMA petition to

other ‘‘loads specified in building

codes’’ may or may not pertain to this

matter. CTMA did not identify those

codes and provided no information on

whether or how they have any

application to cargo tank structural

integrity or accident damage protection.

Therefore, CTMA’s request is denied.

Second, CTMA opposed the 2 ‘‘g’’

design load for rollover damage

protection devices specified in

§ 178.345–8(c)(1). CTMA stated that the

loads on rollover devices, in the case of

longitudinal sliding, would be limited

by the coefficient of sliding friction of

the metal rollover devices on the ground

or pavement and, in the case of lateral

rollover, would be limited even further

by the lateral force leading to continued

overturn of the tank. RSPA discussed

commenters’ requests to reduce the 2

‘‘g’’ design load for rollover protection

at length in the preamble of the final

rule (59 FR 55166). RSPA recognizes

that new designs may be necessary to

gain significant benefits in safety.

RSPA also recognizes that the amount

of force currently imposed in the

horizontal plane is a simplification of

many potential variables which can

come into play during an overturn

accident. Many scenarios are possible:

the impact surface may be smooth or

rough, horizontal or sloping, as hard as

concrete or as soft as sand or damp

earth; the vehicle may roll over an

obstacle such as a guard rail; the cargo

tank may receive an impact over its

entire length or on only a small part of

its exposed surface; etc. CTMA’s

comments on use of the coefficient of

sliding friction might be appropriate for

overturn on a smooth, hard highway

surface, but would impose relatively

moderate loads in comparison to other

rollover scenarios. Accident scenarios

where the rollover damage protection

devices plow through earth or strike
Federal Register / Vol. 60, No. 65 / Wednesday, April 5, 1995 / Rules and Regulations 17399

roadside obstacles impose much greater

loadings on the devices. Therefore,

CTMA’s petition for a reduction in the

safety performance of rollover damage

protection is denied.

Third, CTMA repeated its position

that it is difficult to design rear-end

protection devices in compliance with

the loads prescribed in § 178.345–8(d),

particularly devices which are offset

from the load path. CTMA repeated its

belief previously expressed in

comments that the intent of the

regulation is for the loads to be

transmitted to the tank structure and

absorbed without exceeding the

permitted stresses anywhere along the

load path. CTMA offered no new

information to support this position.

The revised requirements were

discussed in the preamble of the final

rule (59 FR 55167). RSPA believes that

the revised requirements for the DOT

400-series cargo tanks allow engineers

more freedom in the design of rear-end

protection, including approaches

involving energy dissipation and

dampening. Therefore, CTMA’s petition

is denied.

Finally, CTMA commented on the

suitability of applying ASME Code

standards to the cargo tank industry

while not recognizing other ‘‘alternative

quality control program(s).’’ This issue

was fully discussed in the preamble of

the final rule (59 FR 55162). In addition,

this subject was addressed in previous

notices and public meetings under

Docket HM–183 extending over a period

of nearly ten years. CTMA provided no

additional data or information to

support changing the final rule.

Therefore, RSPA’s position remains

unchanged and requirements for using

procedures established under the ASME

Code and the National Board of Boiler

and Pressure Vessel Inspectors (National

Board) Code are retained, and CTMA’s

petition is denied.

CTCL petitioned RSPA to reconsider

amendments allowing a small release of

certain types of ladings from the

pressure relief system, in overturn

accidents, before reclosing to a leaktight position. CTCL stated that it has

designed a vent which releases vapors

instead of lading in an overturn accident

situation, and that this information was

not presented RSPA earlier because the

technology had not yet been developed.

RSPA welcomes the development by

industry of improved valve designs.

RSPA solicited information during the

HM–183C rulemaking proceeding on the

existence of reclosing pressure relief

devices capable of reseating with no loss

of lading and not subject to clogging and

sticking during field service. However,

RSPA believes CTCL has not provided

sufficient information to support

excluding the use of other valve designs

at this time, and CTCL’s petition is

denied.

TTMA petitioned RSPA to continue

allowing a cargo tank manufacturer

holding an ASME ‘‘U’’ stamp to make

repairs to ASME stamped cargo tanks.

TTMA stated that an ASME ‘‘U’’ stamp

holder should not be required to obtain

an ‘‘R’’ stamp from the National Board

and there is no reason why the National

Board cannot continue to inspect repairs

made by a ‘‘U’’ stamp holder.

Furthermore, the National Board

Inspection Code allows repairs to be

made on ASME stamped cargo tanks by

a facility holding an ‘‘R’’ stamp or by a

facility working within an individual

governmental jurisdiction where that

jurisdiction has issued authorization for

the facility to perform repairs.

RSPA explained in the preambles of

the notice of proposed rulemaking

(March 3, 1993; 58 FR 12316) and the

final rule (59 FR 55170) that the

National Board has control over the

quality of work performed by an ‘‘R’’

stamp holder. Jurisdictional

authorization is recognized only within

the governmental boundaries where the

repair facility is located. This type of

authorization may be appropriate for

work performed on stationary vessels,

but not for mobile systems such as cargo

tank motor vehicles. RSPA believes it is

essential to apply a nationally

recognized consensus standard in a

uniform manner regardless of

jurisdiction. Therefore, the requirement

that repairs on DOT specification cargo

tanks certified to the ASME Code must

be performed only by a facility holding

a valid ‘‘R’’ stamp is retained and

TTMA’s petition is denied.

CGA petitioned RSPA to remove the

word ‘‘internal’’ in the first sentence in

§ 178.338–11(c) specifying that each

filling and discharge line for liquids

must be provided with a remotely

controlled internal self-closing stop

valve. CGA pointed out that the word

‘‘internal’’ did not appear in the

provision in the notice of proposed

rulemaking and that requiring internal

valves would bring the cryogenic

flammable lading industry to a standstill

because of the inner tank/outer jacket

configuration of these cargo tanks. RSPA

agrees. It was not RSPA’s intent to

require an ‘‘internal’’ self-closing valve

on these tanks, but to broaden the

requirement to include all flammable

ladings. Therefore, the word ‘‘internal’’

is removed.

NPGA asked RSPA to reconsider its

decision in the final rule that a future

rulemaking would address design

loading requirements for MC 331

specification cargo tanks. The preamble

to the final rule (59 FR 55163) noted

NPGA’s recommendation for uniformity

in design loading requirements for all

DOT specification cargo tanks. In its

petitions, NPGA asked RSPA to extend,

until March 1, 1997, the compliance

date for construction of MC 331 cargo

tank motor vehicles conforming to the

structural integrity requirements

contained in § 178.337–3. It also urged

RSPA to make resolution of stress

analysis a priority project.

RSPA has reviewed the report

previously submitted by NPGA and

found that NPGA’s proposed loadings

for the MC 331 cargo tank are very

similar to the loadings adopted for the

DOT 400-series cargo tanks. This

supports NPGA’s position that cargo

tank motor vehicles encounter similar

loadings regardless of whether the cargo

tank is used to transport a liquid or gas

lading. Therefore, for greater

consistency, RSPA is amending the

structural integrity requirements in

§ 178.337–3 by adopting the same

loadings as specified for the DOT 400-

series cargo tank specifications. In view

of this change, a new paragraph (f) is

added in § 178.23 to provide for a MC

331 specification cargo tank conforming

to the structural integrity requirements

contained in § 178.337–3 or to the

corresponding requirements in effect at

the time of manufacture. However, the

material thickness may not be less than

that required by the ASME Code.

Based on comments received from

CGA that design loadings specified for

MC 338 cargo tanks should not be

revised for consistency with the MC 331

specification, RSPA is not making any

change to § 178.338–3. CGA has advised

it is developing a document to provide

additional guidance to its members on

the design and construction of MC 338

cargo tanks.

The amendment to § 178.337–3

eliminates any need for a delay in the

compliance date for construction of MC

331 cargo tank motor vehicles

conforming to the structural integrity

requirements, and this part of NPGA’s

petition is denied.

Additionally, CGA petitioned RSPA

to allow modifications on cryogenic

cargo tanks originally authorized by

exemption prior to introduction of the

MC 338 specification. In accordance

with § 180.405(d), such cargo tanks

must be marked ‘‘DOT MC 338–E’’

followed by the exemption number.

CGA contends that modifications such

as adding a manhole may require

removal of the outer jacket and

installation of a new shell course to the

inner vessel; only local reinforcement of

the inner vessel was required
17400 Federal Register / Vol. 60, No. 65 / Wednesday, April 5, 1995 / Rules and Regulations

previously. After further consideration,

RSPA agrees with CGA. In establishing

the MC 338 specification, the final rule

(June 16, 1983; 48 FR 27674) stated

‘‘[T]his grandfathering of existing tanks

is necessary to avoid potential severe

economic consequences to some

exemption holders and can be justified

from a safety point of view because of

the thorough technical review involved

in the exemption process,

notwithstanding the fact that certain

aspects of certain exemptions may differ

from this final rule.’’ Nothing in

subsequent rulemakings has changed

this premise. Therefore, in this final

rule, in § 180.413, in paragraph (d)(3),

the introductory text is revised, and a

new paragraph (v) is added to allow MC

338 cargo tanks authorized under

§ 180.405(d) to be structurally modified

provided that no reduction in structural

integrity is incurred and that any

modification is in accordance with the

ASME Code or with the MC 338

specification.

Finally, RSPA has made the following

editorial revisions for clarity: In

§ 178.345–3, in paragraphs (c)(1)(iii)(B)

and (c)(2)(iii)(B), in the second sentence,

the wording ‘‘horizontal pivot of the

tractor’’ is revised to read ‘‘horizontal

pivot of the truck tractor’’. In § 178.345–

14, in paragraph (b)(3), the wording

‘‘Tank MAWP’’ is revised to read ‘‘Tank

maximum allowable working pressure

(MAWP)’’. In § 180.403, a sentence is

added to the definition of modification.

In § 180.405, in paragraph (h)(2),

reference to 40 CFR 60.601 is deleted. In

§ 180.407, in the table in paragraph (c),

under the subheading ‘‘Thickness Test’’

in the first column, the wording ‘‘in

corrosive service, except’’ is revised to

read ‘‘transporting lading corrosive to

the tank, except’’; and paragraphs (d)(1)

(i) and (ii) are revised to remove

duplicative language. In § 180.413,

paragraphs (b)(6) and (d)(10) are revised

to clarify that a repair or modification

affecting the structural integrity of a

pressure cargo tank, with respect to

pressure, must be determined by testing

required by the specification or by

§ 180.407(g)(1)(iv).

Rulemaking Analyses and Notices

1. Executive Order 12866 and DOT

Regulatory Policies and Procedures

This final rule is not considered a

significant regulatory action under

section 3(f) of Executive Order 12866

and was not reviewed by the Office of

Management and Budget. The rule is not

considered significant under the

Regulatory Policies and Procedures of

the Department of Transportation (44 FR

11034). This amendment imposes no

new requirements on affected persons.

The final regulatory evaluation for the

November 1994 final rule is available

for review in the docket. Changes in this

final rule did not warrant revision of the

regulatory evaluation.

2. Executive Order 12612

This final rule has been analyzed in

accordance with the principles and

criteria contained in Executive Order

12612 (‘‘Federalism’’). Federal law

expressly preempts State, local, and

Indian tribe requirements applicable to

the transportation of hazardous material

that cover certain subjects and are not

‘‘substantively the same’’ as the Federal

requirements. 49 U.S.C. 5125(b)(1).

These covered subjects are:

(A) The designation, description, and

classification of hazardous material;

(B) The packing, repacking, handling,

labeling, marking, and placarding of

hazardous material;

(C) The preparation, execution, and

use of shipping documents related to

hazardous material and requirements

respecting the number, contents, and

placement of those documents;

(D) The written notification,

recording, and reporting of the

unintentional release in transportation

of hazardous material; or

(E) The design, manufacturing,

fabricating, marking, maintenance,

reconditioning, repairing, or testing of a

packaging or a container which is

represented, marked, certified, or sold

as qualified for use in transporting

hazardous material.

This final rule addresses the design,

manufacturing, and certain other

requirements for packages represented

as qualified for use in the transportation

of hazardous material. Therefore, this

final rule preempts State, local, or

Indian tribe requirements that are not

‘‘substantively the same’’ as Federal

requirements on these subjects. Section

5125(b)(2) of Title 49 U.S.C. provides

that when DOT issues a regulation

concerning any of the covered subjects

after November 16, 1990, DOT must

determine and publish in the Federal

Register the effective date of Federal

preemption. The effective date may not

be earlier that the 90th day following

the date of issuance of the final rule and

no later than two years after the date of

issuance. RSPA has determined that the

effective date of Federal preemption of

this final rule will be July 5, 1995.

Because RSPA lacks discretion in this

area, preparation of a federalism

assessment is not warranted.

3. Regulatory Flexibility Act

I certify that this final rule will not

have a significant economic impact on

a substantial number of small entities.

This rule applies to manufacturers,

shippers, carriers, and owners of cargo

tanks, some of which are small entities.

There are no direct or indirect adverse

economic impacts for small units of

government, businesses, or other

organizations.

4. Paperwork Reduction Act

This amendment imposes no changes

to the information collection and

recordkeeping requirements contained

in the June 12, 1989 final rule, which

were approved by the Office of

Management and Budget (OMB) under

the provisions of 44 U.S.C. chapter 35

and assigned control number 2137–

0014.

5. Regulation Identifier Number (RIN)

A regulation identifier number (RIN)

is assigned to each regulatory action

listed in the Unified Agenda of Federal

Regulations. The Regulatory Information

Service Center publishes the Unified

Agenda in April and October of each

year. The RIN number contained in the

heading of this document can be used

to cross-reference this action with the

Unified Agenda.

List of Subjects

49 CFR Part 173

Hazardous materials transportation,

Packaging and containers, Radioactive

materials, Reporting and recordkeeping

requirements, Uranium.

49 CFR Part 178

Hazardous materials transportation,

Motor vehicles safety, Packaging and

containers, Reporting and recordkeeping

requirements.

49 CFR Part 180

Hazardous materials transportation,

Motor carriers, Motor vehicle safety,

Packaging and containers, Reporting

and recordkeeping requirements.

In consideration of the foregoing, title

49, chapter I of the Code of Federal

Regulations, is amended as set forth

below:

PART 173—SHIPPERS—GENERAL

REQUIREMENTS FOR SHIPMENTS

AND PACKAGINGS

1. The authority citation for part 173

continues to read as follows:

Authority: 49 U.S.C. 5101–5127, 49 CFR

1.53.

2. In § 173.23, a new paragraph (f) is

added to read as follows:

§ 173.23 Previously authorized packaging.

* * * * *
Federal Register / Vol. 60, No. 65 / Wednesday, April 5, 1995 / Rules and Regulations 17401

(f) An MC 331 cargo tank motor

vehicle must conform to structural

integrity requirements in § 178.337–3 or

to corresponding requirements in effect

at the time of manufacture.

PART 178—SPECIFICATIONS FOR

PACKAGINGS

3. The authority citation for part 178

continues to read as follows:

Authority: 49 U.S.C. 5101–5127, 49 CFR

1.53.

4. In § 178.337–3, paragraph (c) is

revised to read as follows:

§ 178.337–3 Structural integrity.

* * * * *

(c) Shell design. Shell stresses

resulting from static or dynamic

loadings, or combinations thereof, are

not uniform throughout the cargo tank

motor vehicle. The vertical,

longitudinal, and lateral normal

operating loadings can occur

simultaneously and must be combined.

The vertical, longitudinal and lateral

extreme dynamic loadings occur

separately and need not be combined.

(1) Normal operating loadings. The

following procedure addresses stress in

the tank shell resulting from normal

operating loadings. The effective stress

(the maximum principal stress at any

point) must be determined by the

following formula:

S = 0.5(Sy + Sx) ± [0.25(Sy ¥ Sx)2 +

Ss

2]0.5

Where:

(i) S = effective stress at any given point

under the combination of static and

normal operating loadings that can

occur at the same time, in psi.

(ii) Sy = circumferential stress generated

by the MAWP and external

pressure, when applicable, plus

static head, in psi.

(iii) Sx = The following net longitudinal

stress generated by the following

static and normal operating loading

conditions, in psi:

(A) The longitudinal stresses resulting

from the MAWP and external pressure,

when applicable, plus static head, in

combination with the bending stress

generated by the static weight of the

fully loaded cargo tank, all structural

elements, equipment and appurtenances

supported by the cargo tank wall;

(B) The tensile or compressive stress

resulting from normal operating

longitudinal acceleration or

deceleration. In each case, the forces

applied must be 0.35 times the vertical

reaction at the suspension assembly,

applied at the road surface, and as

transmitted to the cargo tank wall

through the suspension assembly of a

trailer during deceleration; or the

horizontal pivot of the truck tractor or

converter dolly fifth wheel, or the

drawbar hinge on the fixed dolly during

acceleration; or anchoring and support

members of a truck during acceleration

and deceleration, as applicable. The

vertical reaction must be calculated

based on the static weight of the fully

loaded cargo tank, all structural

elements, equipment and appurtenances

supported by the cargo tank wall. The

following loadings must be included:

(1) The axial load generated by a

decelerative force;

(2) The bending moment generated by

a decelerative force;

(3) The axial load generated by an

accelerative force; and

(4) The bending moment generated by

an accelerative force; and

(C) The tensile or compressive stress

generated by the bending moment

resulting from normal operating vertical

accelerative force equal to 0.35 times the

vertical reaction at the suspension

assembly of a trailer; or the horizontal

pivot of the upper coupler (fifth wheel)

or turntable; or anchoring and support

members of a truck, as applicable. The

vertical reaction must be calculated

based on the static weight of the fully

loaded cargo tank, all structural

elements, equipment and appurtenances

supported by the cargo tank wall.

(iv) Ss = The following shear stresses

generated by the following static

and normal operating loading

conditions, in psi:

(A) The static shear stress resulting

from the vertical reaction at the

suspension assembly of a trailer, and the

horizontal pivot of the upper coupler

(fifth wheel) or turntable; or anchoring

and support members of a truck, as

applicable. The vertical reaction must

be calculated based on the static weight

of the fully loaded cargo tank, all

structural elements, equipment and

appurtenances supported by the cargo

tank wall;

(B) The vertical shear stress generated

by a normal operating accelerative force

equal to 0.35 times the vertical reaction

at the suspension assembly of a trailer;

or the horizontal pivot of the upper

coupler (fifth wheel) or turntable; or

anchoring and support members of a

truck, as applicable. The vertical

reaction must be calculated based on the

static weight of the fully loaded cargo

tank, all structural elements, equipment

and appurtenances supported by the

cargo tank wall;

(C) The lateral shear stress generated

by a normal operating lateral

accelerative force equal to 0.2 times the

vertical reaction at each suspension

assembly of a trailer, applied at the road

surface, and as transmitted to the cargo

tank wall through the suspension

assembly of a trailer, and the horizontal

pivot of the upper coupler (fifth wheel)

or turntable; or anchoring and support

members of a truck, as applicable. The

vertical reaction must be calculated

based on the static weight of the fully

loaded cargo tank, all structural

elements, equipment and appurtenances

supported by the cargo tank wall; and

(D) The torsional shear stress

generated by the same lateral forces as

described in paragraph (c)(1)(iv)(C) of

this section.

(2) Extreme dynamic loadings. The

following procedure addresses stress in

the tank shell resulting from extreme

dynamic loadings. The effective stress

(the maximum principal stress at any

point) must be determined by the

following formula:

S = 0.5(Sy + Sx) ± [0.25(Sy ¥ Sx)2 +

Ss

2]0.5

Where:

(i) S = effective stress at any given point

under a combination of static and

extreme dynamic loadings that can

occur at the same time, in psi.

(ii) Sy = circumferential stress generated

by MAWP and external pressure,

when applicable, plus static head,

in psi.

(iii) Sx = the following net longitudinal

stress generated by the following

static and extreme dynamic loading

conditions, in psi:

(A) The longitudinal stresses resulting

from the MAWP and external pressure,

when applicable, plus static head, in

combination with the bending stress

generated by the static weight of the

fully loaded cargo tank, all structural

elements, equipment and appurtenances

supported by the tank wall;

(B) The tensile or compressive stress

resulting from extreme longitudinal

acceleration or deceleration. In each

case the forces applied must be 0.7

times the vertical reaction at the

suspension assembly, applied at the

road surface, and as transmitted to the

cargo tank wall through the suspension

assembly of a trailer during

deceleration; or the horizontal pivot of

the truck tractor or converter dolly fifth

wheel, or the drawbar hinge on the fixed

dolly during acceleration; or the

anchoring and support members of a

truck during acceleration and

deceleration, as applicable. The vertical

reaction must be calculated based on the

static weight of the fully loaded cargo

tank, all structural elements, equipment

and appurtenances supported by the

cargo tank wall. The following loadings

must be included:
17402 Federal Register / Vol. 60, No. 65 / Wednesday, April 5, 1995 / Rules and Regulations

(1) The axial load generated by a

decelerative force;

(2) The bending moment generated by

a decelerative force;

(3) The axial load generated by an

accelerative force; and

(4) The bending moment generated by

an accelerative force; and

(C) The tensile or compressive stress

generated by the bending moment

resulting from an extreme vertical

accelerative force equal to 0.7 times the

vertical reaction at the suspension

assembly of a trailer, and the horizontal

pivot of the upper coupler (fifth wheel)

or turntable; or the anchoring and

support members of a truck, as

applicable. The vertical reaction must

be calculated based on the static weight

of the fully loaded cargo tank, all

structural elements, equipment and

appurtenances supported by the cargo

tank wall.

(iv) Ss = The following shear stresses

generated by static and extreme

dynamic loading conditions, in psi:

(A) The static shear stress resulting

from the vertical reaction at the

suspension assembly of a trailer, and the

horizontal pivot of the upper coupler

(fifth wheel) or turntable; or anchoring

and support members of a truck, as

applicable. The vertical reaction must

be calculated based on the static weight

of the fully loaded cargo tank, all

structural elements, equipment and

appurtenances supported by the cargo

tank wall;

(B) The vertical shear stress generated

by an extreme vertical accelerative force

equal to 0.7 times the vertical reaction

at the suspension assembly of a trailer,

and the horizontal pivot of the upper

coupler (fifth wheel) or turntable; or

anchoring and support members of a

truck, as applicable. The vertical

reaction must be calculated based on the

static weight of the fully loaded cargo

tank, all structural elements, equipment

and appurtenances supported by the

cargo tank wall;

(C) The lateral shear stress generated

by an extreme lateral accelerative force

equal to 0.4 times the vertical reaction

at the suspension assembly of a trailer,

applied at the road surface, and as

transmitted to the cargo tank wall

through the suspension assembly of a

trailer, and the horizontal pivot of the

upper coupler (fifth wheel) or turntable;

or anchoring and support members of a

truck, as applicable. The vertical

reaction must be calculated based on the

static weight of the fully loaded cargo

tank, all structural elements, equipment

and appurtenances supported by the

cargo tank wall; and

(D) The torsional shear stress

generated by the same lateral forces as

described in paragraph (c)(2)(iv)(C) of

this section.

* * * * *

§ 178.338–11 [Amended]

5. In § 178.338–11, in paragraph (c)

introductory text, in the first sentence,

the wording ‘‘remotely controlled

internal self-closing stop valve’’ is

revised to read ‘‘remotely controlled

self-closing shut-off valve’’.

§ 178.345–3 [Amended]

6. In § 178.345–3, in paragraphs

(c)(1)(iii)(B) and (c)(2)(iii)(B), in the

second sentence, the wording

‘‘horizontal pivot of the tractor’’ is

revised to read ‘‘horizontal pivot of the

truck tractor’’.

§ 178.345–14 [Amended]

7. In § 178.345–14, in paragraph

(b)(3), the wording ‘‘Tank (MAWP)’’ is

revised to read ‘‘Tank maximum

allowable working pressure (MAWP)’’.

PART 180—CONTINUING

QUALIFICATION AND MAINTENANCE

OF PACKAGINGS

8. The authority citation for part 180

continues to read as follows:

Authority: 49 U.S.C. 5101–5127, 49 CFR

1.53.

9. In § 180.403, the introductory text

in the definition for ‘‘modification’’ is

revised to read as follows:

§ 180.403 Definitions.

* * * * *

Modification means any change to the

original design and construction of a

cargo tank or a cargo tank motor vehicle

which affects its structural integrity or

lading retention capability. Any

modification which involves welding on

the cargo tank wall also must meet all

requirements for ‘‘Repair’’ as defined in

this section. * * *

* * * * *

§ 180.405 [Amended]

10. In § 180.407, in paragraph (h)(2),

in the second sentence, the reference

‘‘40 CFR 60.501 and 60.601’’ is revised

to read ‘‘40 CFR 60.501’’.

11. In § 180.407, paragraphs (d)(1)(i)

and (ii) are revised to read as follows:

§ 180.407 Requirements for test and

inspection of specification cargo tanks.

* * * * *

(d) * * *

(1) * * *

(i) Visual inspection is precluded by

internal lining or coating, or

(ii) The cargo tank is not equipped

with a manhole or inspection opening.

* * * * *

§ 180.407 [Amended]

11a. In addition, in § 180.407, in the

table in paragraph (c), under the

subheading ‘‘Thickness Test’’ in the first

column, the wording ‘‘in corrosive

service, except’’ is revised to read

‘‘transporting material corrosive to the

tank, except’’.

12. In § 180.413, paragraphs (b)(6),

((d)(3) introductory text and (d)(10) are

revised, and a new paragraph (d)(3)(v) is

added to read as follows:

§ 180.413 Repair, modification, stretching,

or rebarrelling of cargo tanks.

* * * * *

(b) * * *

(6) The suitability of any repair

affecting the structural integrity of the

cargo tank must be determined by the

testing required either in the applicable

manufacturing specification, or in

§ 180.407(g)(1)(iv).

* * * * *

(d) * * *

(3) Except as provided in paragraph

(d)(3)(v) in this section, all new material

and equipment, and equipment affected

by modification, stretching or

rebarrelling must meet the requirements

of the specification in effect at the time

such work is performed, and must meet

the applicable structural integrity

requirements (§§ 178.337–3, 178.338–3,

or 178.345–3 of this subchapter). The

work must conform to the requirements

of the applicable specification as

follows:

* * * * *

(v) For Specification MC 338 cargo

tanks, the provisions of specification

MC 338. However, structural

modifications to MC 338 cargo tanks

authorized under § 180.405(d) may

conform to applicable provisions of the

ASME Code instead of specification MC

338, provided the structural integrity of

the modified cargo tank is at least

equivalent to that of the original cargo

tank.

* * * * *

(10) The suitability of any

modification affecting the structural

integrity of the cargo tank, with respect

to pressure, must be determined by the

testing required either in the applicable

manufacturing specification, or in

§ 180.407(g)(1)(iv).

* * * * *

§ 180.413 [Amended]

13. In addition, in § 180.413, the

following changes are made:

a. In paragraph (d)(3)(iii), at the end

of the paragraph, the word ‘‘and’’ is

removed.

b. In paragraph (d)(3)(iv), at the end

of the paragraph, the period is removed

and ‘‘; and’’ is added in its place.
Federal Register / Vol. 60, No. 65 / Wednesday, April 5, 1995 / Rules and Regulations 17403

Issued in Washington, DC on March 30,

1995, under authority delegated in 49 CFR

Part 1.

Ana Sol Gutie ́rrez,

Deputy Administrator, Research and Special

Programs Administration.

[FR Doc. 95–8349 Filed 4–4–95; 8:45 am]

BILLING CODE 4910–60–P