GB 8335 Chinese Gas Cylinder Screw Thread

GB 8335 Chinese Gas Cylinder Screw Thread

GB 8335:2011 Forward
This standard is redrafted and modified in relation to ISO 11363-1:2010 Gas Cylinders -17E and 25E Taper Threads for Connection of Valves to Gas Cylinders and DIN 477-1:1979 Gas Cylinder Valve, but it is not equivalent to them in consistency. In terms of the contents referenced by this standard, the basic dimension of PZ19.2 and 17E taper thread as well as that of PZ27.8 and 25E taper thread are made to be completely consistent but the different deviation is retained.

Scope
This standard specifies the terms, symbols, basic profile and dimension of taper thread and cylindrical pipe thread for gas cylinders. This standard is applicable to taper thread connecting the neck to valve of gas cylinder and cylindrical pipe thread connecting cap and neck ring of such cylinder. The taper thread connecting the fusible plug to plug seat of gas cylinder with safety device may also be used by reference to this standard.

NOTE:
There were a number of screw thread size changes in the GB 8335:2011 from the previous version GB 8335:1998. These are identified in the Foreword.

Thread Designations
There are several screw thread designations specified in GB 8335.
PZ39.0 is 39.0mm 12-TPI tapered screw thread with 55° included angle
PZ30.3 is 30.3mm 14-TPI tapered screw thread with 55° included angle
PZ27.8 is 28.8mm 14-TPI tapered screw thread with 55° included angle (similar to 25E)
PZ19.2 is 19.2mm 14-TPI tapered screw thread with 55° included angle (similar to 17E)
PG80 is 80mm 11-TPI cylindrical screw thread with 55° included angle
M85x16(P4) is 85mm 4-pitch 16-lead 4-start cylindrical screw thread with 60° included angle
M80x3 is 80mm 3.0 pitch thread cylindrical screw with 60° included angle

Specified Tapered Thread Gauges
Clause 4.2 defines a single tapered L1 gage to test the male or female part screw threads.
Clause 4.6 allows for additional gages is agreed upon by interested parties.

Disclaimer:
This data is provided for general information only. The intention is to provide accurate information; regardless; errors may exist in the supplied information. If accuracy is critical, base your final decisions on the data provided in the root document: GB8335; which is a copyrighted document. To purchase copies visit an Authorized Reseller.

Comments:
Original Posting: 4/5/2018
Last Revision:
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