§ 78.54-2 Type, size, and service pressure-(a) Type and size. Must be welded or brazed type with longitudinal fusionwelded seam. 240 pounds nominal water capacity. Cylinders closed in by spinning process not authorized.

(b) Service pressure.1 240 pounds per square inch.

§ 78.54-3 Inspection by whom and where. (a) By competent and disinterested inspector acceptable to the Bureau of Explosives; chemical analyses and tests, as specified, to be made within limits of the United States. This requirement is necessary because of the present emergency and until further order of the Commission.

§ 78.54-4 Duties of inspector. (a) Inspect all material and reject any not complying with requirements.

(b) Verify chemical analysis of each heat of material by analysis or by obtaining certified analysis: Provided, That a certificate from the manufacturer thereof, giving sufficient data to indicate compliance with requirements, is acceptable when verified by check analyses of samples taken from one cylinder out of each lot of 200 or less.

(c) Verify compliance of cylinders with all requirements including markings; inspect inside before closing in both ends; verify heat treatment as proper; obtain samples for all tests and check chemical analyses; witness all tests; verify threads by gauge; report volumetric capacity and tare weight (see report form) and minimum thickness of wall noted.

(d) Render complete report (§ 78.54– 22) to purchaser, cylinder maker, and the Bureau of Explosives.

§ 78.54-5 Steel. (a) Steel shall be plain carbon steel of American Society for Testing Materials firebox quality with carbon content not in excess of 0.25 percent.

1 The "service pressure" limits the use of the cylinder. It is shown by marks on cylinder; for example, ICC 4B240-FLW.

§ 78.54-6

Identification of material.

(a) Required; any suitable method.

§ 78.54-7 Defects. (a) Material with seams, cracks, laminations, or other injurious defects, not authorized.

§ 78.54-8 Manufacture. (a) By best appliances and methods; dirt and scale to be removed as necessary to afford proper inspection; no defect acceptable that is likely to weaken the finished cylinder appreciably; reasonably smooth and uniform surface finish required. Exposed bottom welds on cylinders over 18" long must be protected by foot rings. Seams must be made as follows:

(1) Circumferential seams by welding or by brazing: Heads attached by brazing must have a driving fit with the shell, unless the shell is crimped, swedged, or curled over the skirt or flange of the head, and be thoroughly brazed until complete penetration by the brazing material of the brazed joint is secured. Depth of brazing from end of shell must be at least four times the thickness of shell metal.

(2) Longitudinal fusion-welded seam shall be of the double-welded butt type. Filler metal may be added from one side when and if means are provided for accomplishing complete penetration and reinforcement on both sides of the joint. Welding procedure and welding operators shall be qualified for the manufacture of pressure vessels in accordance with paragraph U-69 of the Rules for Construction of Unfired Pressure Vessels, Section VIII of the American Society of Mechanical Engineers Boiler Construction Code, 1943 Edition including Addenda to 1946 Edition.

§ 78.54-9 Welding or brazing. (a) The attachment to the tops and bottoms only of cylinders by welding or brazing of neckrings, footrings, handles, bosses, pads, and valve protection rings is authorized provided that such attachments and the portion of the container to which they are attached are made of weldable steel, the carbon content of which must not exceed 0.25 percent.

d inside diameter in inches.

§ 78.54-11 Heat treatment. (a) Each cylinder shall be thermally stress-relieved after all initial welding and seam repair welding operations have been completed and prior to the hydrostatic test.

§ 78.54-12 Openings in cylinders. (a) Each opening in cylinders, except those for safety devices, must be provided with a fitting, boss, or pad, securely attached to cylinder by brazing or by welding or by threads. Fitting, boss, or pad must be of steel suitable for the method of attachment employed, and which need not be identified or verified as to analysis, except that if attachment is by welding, carbon content must not exceed 0.25 percent. If threads are used, they must comply with the following:

(1) Threads must be clean cut, even, without checks, and tapped to gauge.

(2) Taper threads to be of length not less than as specified for American Standard taper pipe threads.

(3) Straight threads, having at least 4 engaged threads, to have tight fit and calculated shear strength at least 10 times the test pressure of the cylinder; gaskets required, adequate to prevent leakage.

(b) Closure of fitting, boss, or pad must be adequate to prevent leakage.

§ 78.54-13 Safety devices and protection for valves, safety devices, and other connections, if applied. (a) Devices must be as required by the Interstate Commerce Commission's regulations that apply (see §§ 73.34 (f) and 73.301 (i) of this chapter).

§ 78.54-14 Hydrostatic test. (a) By water-jacket, or other suitable method, operated so as to obtain accurate data. Pressure gauge must permit reading to accuracy of 1 percent. Expansion gauge must permit reading of total expansion to accuracy either of 1 percent or 0.1 cubic centimeter.

(b) Pressure must be maintained for 30 seconds and sufficiently longer to insure complete expansion. Any internal pressure applied after heat-treatment

and previous to the official test must not exceed 90 percent of the test pressure. If, due to failure of the test apparatus, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent or 100 pounds per square inch, whichever is the lower.

(c) Permanent volumetric expansion must not exceed 10 percent of total volumetric expansion at test pressure.

(d) Each cylinder shall be subjected to the hydrostatic test and test pressure shall be at least two and two thirds times the service pressure. Following this test, each cylinder shall be subjected to a dry air-pressure test of two times the service pressure. The cylinder shall be thoroughly dry before air test is applied, and during test welded seams shall be examined for leaks, either by submerging the cylinders in liquid, or by painting all welded seams with a solution suitable for the detection of leaks.

(e) One finished cylinder out of each lot, which appears to the inspector to be the least likely to meet the test, shall be selected by the inspector from each lot of 200 or less successively produced and shall be hydrostatically tested to destruction and shall not burst at a pressure less than six times the service pres

sure.

§ 78.54-15 Physical test. (a) To determine yield strength, tensile strength, elongation, and reduction of area of material. Required on 2 specimens cut from 1' cylinder, or part thereof heattreated as required, taken at random out of each lot of 200 or less.

(b) Specimens must be: Gauge length 8 inches with width not over 11⁄2 inches; or, gauge length 2 inches with width not over 11⁄2 inches; provided, that gauge length at least 24 times thickness with width not over 6 times thickness is authorized when cylinder wall is not over 316 inch thick. The specimen, exclusive of grip ends, must not be flattened. Grip ends may be flattened to within one inch of each end of the reduced section. When size of cylinder does not permit securing straight specimens, the specimens may be taken in any location or direction and may be straightened or flattened cold, by pressure only, not by

1 For lots of 30 or less, physical tests are authorized to be made on a ring at least 8 inches long cut from each cylinder and subjected to same heat treatment as the finished cylinder.

blows; when specimens are so taken and prepared, the inspector's report must show in connection with record of physical tests detailed information in regard to such specimens. Heating of specimen for any purpose is not authorized.

(c) The yield strength in tension shall be the stress corresponding to a permanent strain of 0.2 percent of the gauge length.

(1) The yield strength shall be determined by either the "offset" method or the "extension under load" method as prescribed in ASTM Standard E8-42.

(2) In using the "extension under load" method, the total strain (or "extension under load") corresponding to the stress at which the 0.2 percent permanent strain occurs may be determined with sufficient accuracy by calculating the elastic extension of the gauge length under appropriate load and adding thereto 0.2 percent of the gauge length. Elastic extension calculations shall be based on an elastic modulus of 30,000,000. In the event of controversy, the entire stress-strain diagram shall be plotted and the yield strength determined from the 0.2 percent offset.

(3) For the purpose of strain measurement, the initial strain shall be set while the specimen is under a stress of 12,000 pounds per square inch, the strain indicator reading being set at the calculated corresponding strain.

(4) Cross-head speed of the testing machine shall not exceed % inch per minute during yield strength determination.

§ 78.54-16 Acceptable results for physical tests. (a) Elongation at least 40 percent for 2 inch gauge length or at least 20 percent in other cases; yield strength not over 73 percent of tensile strength; flattening test not required.

§ 78.54-17 Weld tests. (a) A bend test specimen shall be cut from the cylinder used for the physical tests specified in $ 78.54-15. Specimen shall be taken across the seam, shall be 11⁄2 inches wide, edges shall be parallel and rounded with a file, and back-up strip, if used, shall be removed by machining. The specimen shall be bent to refusal in the guided bend test jig shown in the drawing in § 78.54-23. The root of the weld (inside surface of the cylinder) shall be located away from the ram of the jig. No specimen shall show a crack exceeding %

inch in any direction upon completion of the test. Should this specimen fail to meet the requirements, two additional specimens from the same cylinder shall be tested, and if either of these fails to meet the requirements, the entire lot represented shall be rejected.

(b) In addition to the guided bend test, a reduced section tension test shall be made transverse to the weld and meet the requirements of paragraph Q-109 of section IX of the American Society of Mechanical Engineers Boiler Construction Code, 1943 Edition including Addenda to 1946 Edition. Should this specimen fail to meet the requirements, two additional specimens from the same cylinder shall be tested, and if either of these fails to meet the requirements, the entire lot represented shall be rejected.

§ 78.54-18 Radiographic examination. (a) One finished longitudinal seam shall be selected at random from each lot of 100 or less successively produced and be radiographically examined throughout its length in accordance with subparagraph (h) of paragraph U-68 of the American Society of Mechanical Engineers Unfired Pressure Vessel Code. Should the radiographs fail to meet the requirements two additional seams of the same lot shall be examined, and if either of these fails to meet the requirements the entire lot shall be rejected.

§ 78.54-19 Rejected cylinders. (a) Reheat treatment authorized; subsequent thereto, acceptable cylinders must pass all prescribed tests. Repair of brazed seams by brazing and welded seams by welding is authorized.

§ 78.54-20 Marking. (a) Marking required on each cylinder by stamping plainly and permanently on shoulder, top head, or neck as follows:

(1) ICC-4B240-FLW.

(2) A serial number and an identifying symbol (letters); location of number to be just below the ICC mark; location'

1 Symbol in front of or following the number with ample space between or symbol and serial number stamped into welded or brazed-on valve spud directly above the ICC specification mark located head of cylinder are also authorized. Other variations in location authorized only when necessitated by lack of space.

Example:

ICC-4B240-FLW

on

1234

XY

of symbol to be just below the number. The symbol and numbers must be those of the purchaser, user, or maker. The symbol must be registered with the Bureau of Explosives; duplications unauthorized.

(3) Inspector's official mark near serial number, date of test (such as 12-50 for December 1950), so placed that dates of subsequent test can be easily added. § 78.54-21 Size of marks. (a) At least 14" high if space permits.

§ 78.4-22 Inspector's report. (a) Required to be clear, legible, and in following form:

(were-were not)

All material, such as plates, billets and seamless tubing, was inspected and each cylinder was inspected both before and after closing in the ends; all that was accepted was found free from seams, cracks, laminations, and other defects which might prove injurious to the strength of the cylinder. The processes of manufacture and heat treatment of cylinders were supervised and found to be efficient and satisfactory.

The cylinder walls were measured and the minimum thickness noted was inch. The outside diameter was determined by a close approximation to be inches. The

wall stress was calculated to be pounds per square inch under an internal pressure of pounds per square inch.

---

Hydrostatic tests, tensile tests of material, and other tests, as prescribed in specification No. ICC-4B240FLW were made in the presence of the inspector and all material and cylinders accepted were found to be in compliance with the requirements of that specification. Records thereof are attached hereto.

I hereby certify that all of these cylinders proved satisfactory in every way and comply with the requirements of Interstate Commerce Commission specification No. 4B240FLW except as follows: Exceptions:

(Signed)

(Place) (Date)

Inspector.

inches long Company Company