(1) By greatest appliances and strategies. No defect is appropriate that is likely to weaken the completed container appreciably. A reasonably easy and uniform surface area complete is needed.

(iii) The minimal test pressure needs to be preserved not less than 30 seconds and adequately for a longer time to ensure finish enlargement. Any inside strain utilized following heat-treatment and before the official test may well not exceed 90 percent from the exam strain.

(ii) A person cylinder must be picked from Every single ton and become hydrostatically tension tested to destruction. If this cylinder bursts beneath 5 (five) instances the provider force, then two additional cylinders from the same whole lot since the Earlier examined cylinder has to be selected and subjected to this check.

A DOT 8AL cylinder is really a seamless steel cylinder by using a service tension of 250 psig. Nonetheless, the attachment of heads by welding or by brazing by dipping system and also a welded circumferential body seam is licensed. Longitudinal seams usually are not authorized.

Screening is required on two (two) specimens removed from one particular cylinder or aspect thereof taken at random out of each number of 200 or much less. Samples has to be eradicated right after warmth remedy as illustrated in appendix A to this subpart.

(three) Title plates are approved, delivered that they may be completely and securely attached to your cylinder. Attachment by possibly brazing or welding isn't permitted. Attachment by soldering is permitted offered steel temperature doesn't exceed 500 °F.

(iii) For the objective of pressure measurement, the initial pressure needs to be established although the specimen is under a stress of 12,000 psig and also the pressure indicator examining has to be set with the calculated corresponding strain.

(iii) Every single ligament which separates two openings has to be a minimum of thrice the common on the diameters of The 2 openings.

(1) Marking on Every cylinder should be stamped plainly and permanently on or near the shoulder, major head, neck or valve defense collar that is completely hooked up on the cylinder and forming integral part thereof.

Reheat cure is licensed for rejected cylinders. Nevertheless, Each individual reheat taken care of cylinder need to subsequently pass all check here the prescribed assessments. Mend by welding will not be approved.

(iii) For the purpose of pressure measurement, the Preliminary pressure reference have to be set though the specimen is under a strain of twelve,000 psi and also the pressure indicator reading through staying set for the calculated corresponding pressure.

Previous to any check, all cylinders should be subjected to an answer heat procedure and growing older therapy suitable for the aluminum alloy utilized.

(four) As a security precaution, When the maker elects to generate this take a look at before the hydrostatic check, he should really design his equipment so that the stress is applied to the smallest area practicable, throughout the level of closure, and to be able to make use of the smallest feasible quantity of air or gasoline.

(iii) The following method have to be used to determine the maximum longitudinal tensile stress as a result of hydrostatic check stress: