GB 12135-1999 Cylinder Regular Inspection Station Technical Conditions
1 Scope
This standard specifies the technical requirements, test methods, inspection rules, and acceptance criteria for the safety regular inspection station for cylinder.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding errata) to, or revised editions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative document applies.
GB/T 280-1994 Specification for steel cylinder for dissolved acetylene
GB 4379-89 Coated cylinder for dissolved acetylene
GB/T 17116-1997 General requirements for liquefied petroleum gas cylinders
GB/T 17526-1998 Steel pressure vessels - Spherical and periodoid shells - Strength and hardness tests
GB/T17913-1999 Seamless steel cylinders
GB/T 17914-1999 Non-refillable metallic gas cylinder
GB/T 17915-1999 Seamless steel gas cylinders
GB/T 17091-1997 Seamless aluminium-alloy cylinders
3 Technical requirements
3.1 Identification
3.1.1 All cylinders of the same structure, material and process condition shall have o information including volume and weight, equal to or less than 0.06L volume and 5kg weight shall indicate the same information that refers to 3.2.3 and 3.2.4 requirement.
3.1.2 The cylinder containing liquefied petroleum gas with a volume greater than or equal to 2L, should be welded with a welder with welding qualification. The welding and their qualification should follow the current GB/T 17116-1997.
3.2 Structural requirements
3.2.1 The cylinder should be manufactured by consistent raw material source, and the same wall thickness. The thickness of cylinders should follow the related standards.
3.2.2 For double row bottom or ring reinforcement, it should have an article to identify, and either of which should not have a decarburized layer that exceeds 0.3mm, a bend more than 3 degrees more than 120 degrees and with no obvious broadings or surface pits.
3.2.3 The cylinder shell should have complete welding joint, no welding defects.
3.2.4 The welding seam should satisfy the following requirements:
a) the weld seam should has no visual defects, no rust, no scratch, no dent or decarburized layer;
b) for narrow-thick, fillet or plug weld, the weld should completely covers the thick section.
3.2.5 The valve thread should follow the currently GB 4248-83 standard. The thread should have no crack and no decarburized layer, and should meet the strength requirements in the standard.
3.2.6 The thread of the branch-piping and counter clamp should follow the standard GB/T 479-2003, and should meet the strength requirements in the standard.
3.2.7 The counter clamp should be fixed evenly, and at least two pieces.
3.3 Test requirements
3.3.1 The cylinders should be inspected and tested in accordance with the relevant standards.
3.3.2 The hydraulic test of steel cylinders should be carried out in QC laboratory in accordance with GB/T 17526-1998, and the pressure will last for 1 min and not less than 0.5MPa.
3.3.3 The liquefied petroleum gas contained inside leaking is not greater than 2mL/min at the test pressure not less than 0.5MPa.
3.3.4 The non-refillable metallic gas cylinder should satisfy the bursting pressure according to the requirements of GB/T 17091-1997.
4 Inspection rules
4.1 All cylinders should be carefully checked before entering into regular inspection station.
4.2 The cylinder must pass the general inspection and failing which shall not be accepted.
4.3 During routine inspection, any cracks, corrosion, welding defects, bulging, buckling, decarburized layer, and other defects should not exceed the allowable values specified in the relevant standards.
4.4 All cylinders should pass subsequent tests once passed the routine inspection. Any defects found during the subsequent test shall be treated in the same way as these found during routine inspection.
4.5 If a cylinder requires to be repainted or recoated during the routine inspection or subsequent tests, it should also meet the requirements of GB 4379-89 or GB/T 17091-1997.
4.6 All valves should pass the strength test in accordance with the requirements of current GB 4248-83.
5 Acceptance
5.1 All cylinders should meet the requirements of this standard, unless otherwise agreeded by both parties.
5.2 If a cylinder fails the regular inspection due to its material, processes or structure, the inspection station should issue a retrieval notice for replacement for immediate retrieval.
5.3 All cylinders whose repairs are unacceptable should be disposed of properly.
5.4 Any cylinders which may cause safety hazards should not been accepted.
5.5 Unless otherwise agreeded by both parties, the acceptance criteria should meet the requirements of this standard.
