HG/T 3704-2003 in English

1 Scope

This standard specifies the product classification, requirements, test methods, inspection rules, marking, packaging, transportation and storage of valves lined with fluoroplastics.

This standard is applicable to valves lined with fluoroplastics for flange connection and wafer connection.

2 Normative References

The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies.

GB/T 2828 Sampling Procedures and Tables for Periodic Inspection by Attributes
GB/T 9113.1 Integral Steel Pipe Flanges with Flat Face or Raised Face
GB/T 12220 General Purpose Industrial Valves — Marking
GB/T 12221 Metal Valves for Use in Flanged Pipe Systems — Face-to-face and Centre-to-face Dimensions
GB/T 12224 General Requirements for Industrial Steel Valves
GB/T 12233 General Purpose Industrial Valves — Casting Iron Globe Valves and Lift Check Valves
GB/T 12235 General Purpose Industrial Valves — Flanged Steel Globe Valves and Lift Check Valves
GB/T 12236 General Purpose Industrial Valves — Steel Swing Check Valve
GB/T 12237 General Purpose Industrial Valves — Flanged and Butt-weld End Steel Ball Valves
GB/T 12238 General Purpose Industrial Valve — Flanged and Wafer Butterfly Valves
GB/T 12239 General Purpose Industrial Valves — Diaphragm Valves
GB/T 12240 General Purpose Industrial Valves — Iron Plug Valves
GB/T 13927 Pressure Testing for General Purpose Valves
GB/T 15188 Face-to-face, Centre-to-face, End-to-end and Centre-to-end Dimensions of Valves
GB/T 17241 Cast Iron Pipe Flanges
HG/T 2167 Daiflon
HG/T 2902 Polytetrafluoroethylene Molding Powder

Foreword I
1 Scope
2 Normative References
3 Product Classification
3.1 Classification, Designation and Type of Valves
3.2 Lining Materials and Symbols
4 Requirements
4.1 Lining Materials
4.2 Type and Tolerance
4.3 Connecting Type
4.4 Appearance of Fluoroplastics Lining
4.5 Pressure Test
4.6 High Frequency Spark Test
4.7 Vacuum Test
4.8 Assembly
5 Inspection Items and Test Methods
5.1 Lining Materials
5.2 Dimensional tolerance
5.3 Flange dimensions
5.4 Appearance of Fluoroplastics Lining
5.5 Pressure Test
5.6 High Frequency Spark Test
5.7 Vacuum Test
5.8 Assembly
6 Inspection Rules
6.1 Inspection Categories
6.2 Delivery Inspection
6.3 Type Inspection
7 Marking, Packaging, Transportation and Storage
Annex A (Normative) Structural Type, Lining Wall Thickness and Face-to-face Dimensions of Valves