(two) The look company temperature could be the coldest temperature for which a cylinder is acceptable. The needed style provider temperatures for each cryogenic liquid is as follows:
(iii) Each ligament which separates two openings have to be a minimum of three times the standard with the diameters of the two openings.
Pressure-retaining resources should be determined by any acceptable system that does not compromise the integrity with the cylinder. Plates and billets for hotdrawn cylinders has to be marked with the heat number.
Cylinders need to be produced working with tools and processes ample making sure that Every single cylinder made conforms to the necessities of the subpart. No defect is permitted that is probably going to weaken the concluded cylinder appreciably.
(i) Minimum amount thickness of heads and bottoms should be not a lot less than 90 p.c with the necessary thickness of the side wall.
(2) Once the porosity of every cylinder will not be regarded, a cylinder taken at random from many 200 or much less have to be examined for porosity. Should the take a look at cylinder fails, Each and every cylinder in the ton can be analyzed independently and people cylinders that pass the check are acceptable.
(vi) Affect exam specimens should be cooled to the design services temperature. The apparatus for tests the specimens must conform to needs of ASTM Common E 23. The take a look at piece, as well as the managing tongs, need to be cooled for just a length of time adequate to reach the company temperature.
(iv) A brass fitting can be brazed towards the steel manager or flange on cylinders made use of as ingredient aspects of handheld fire extinguishers.
(iii) Straight threads obtaining at least 4 engaged threads, to obtain tight in shape and calculated shear energy at the least 10 occasions the examination tension in the container; gaskets demanded, sufficient to prevent leakage.
(one) Within this specification, a “ton” implies a bunch of cylinders successively produced acquiring the identical:
Markings on each container needs to be stamped plainly and completely on a permanent attachment or on the metal nameplate completely secured into the container by indicates apart from delicate solder.
Notwithstanding the variation furnished With this paragraph, each container ought to in any other case conform to a DOT 2Q container in accordance with § 178.33a. The next situations also apply below Variation 1—
(seven) Other than as or else supplied in paragraph (g)(six) of this segment, all cylinders, if water quenched or quenched by using a liquid generating a cooling fee in surplus of 80 per cent of the cooling rate of h2o, have to be inspected from the magnetic particle, dye penetrant or ultrasonic process to detect the presence here of quenching cracks. Any cylinder designed to the necessities for specification 3AA and found to have a quenching crack must be rejected and will not be requalified.
One particular completed cylinder selected at random out of each and every lot of 500 or a lot less successively generated has to be hydrostatically analyzed to four