CJ/T 300-2008Water hammer arrestor for water supply systems of buildings (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard is CJ/T 300-2008 "building water hammer absorbers," the amendment. This standard compared with CJ/T 300-2008, the main to technical changes are as follows.

--- Removed the original preamble equivalent to the use of the American Society of Sanitation Engineering ASSE1010-2004 "water hammer absorbers performance requirements" Expression

--- Modify the scope of application of nominal pressure;

--- Modify the normative references in the introductory language and normative references made changes;

--- Modify the definition of buffer pressure chamber and buffer pressure chamber volume;

--- Modify the term "maximum working pressure" as "system pressure" and redefine;

--- Modify the "preset inflation pressure" and "pressure relief buffer chamber" definition;

--- Increased copper alloy shell material;

--- Modify the structure of the absorber type of classification;

--- Removed the "Materials" section of the original table 2 and Table 3;

--- Modify the water hammer maximum allowable peak pressure calculation. P2 = 1.3P1;

--- Modify the absorption capacity of water hammer absorbers should be less than 1.3 times the system pressure;

--- Increased the appearance of inspection as a factory inspection project;

--- Removed the "Sampling" chapter of the original table 5;

--- Modify the original 9.2.1d) medium-sized inspection of the inspection period (from five years to three years);

--- Deleted Appendix A screwdriver gut-type water hammer absorber Original Figure A.2, flange-mounted gutter type water hammer absorber Figure A.5 and Gall bladder buffer gas pressure chamber without pre-pressure water hammer absorber original A.8, and modify the terms of the statement;

--- Modify and complete Appendix B model structure of the type of formulation;

--- Removed the original Appendix C;

--- Modify the original appendix D close the valve to close the entire time T of the formula (D.1) for the type (C.1) (Inequality in the parent bracket Add a sum of factor U) and change Appendix D to Appendix C.

This standard in the revision process, the buffer pressure chamber is not filled with pre-pressure water hammer absorbers structure type, working conditions, and its corresponding Buffer pressure chamber volume, absorption performance and other parameters are equivalent to the United States Water Supply and Drainage Association PDI-WH201-2010 "water hammer absorber." this standard proposed by the Ministry of Housing and Urban Standard and Design Institute.

This standard by the Ministry of Housing and Urban Water Supply and Drainage Municipal Standardization Technical Committee centralized.

This standard was drafted. Guangdong Yongquan Valve Technology Co., Ltd., Guangdong Cast Tak Industrial Co., Ltd., Beijing Yongquan Tengda valve technology Limited company.

1 Scope

This standard specifies the construction of water hammer absorbers (hereinafter referred to as absorbers) terms and definitions, structure type, product type, material, to Requirements, test methods, inspection rules, signs and product specifications and packaging and storage.

This standard applies to the nominal size of DN15 ~ DN400, the nominal pressure is not greater than PN50, temperature 0 °C ~ 70 °C of building water supply Hammer absorber.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version applies to this article Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB 150 (all parts) pressure vessels GB/T 196 ordinary thread basic size GB/T 197 ordinary thread tolerances GB/T 1047 pipe element DN (nominal size) of the definition and selection GB/T 1048 pipe element PN (nominal pressure) definition and selection GB/T 3098 (all parts) Fastener mechanical properties GB/T 7306.2 55 ° sealing pipe threads - Part 2. Female and female conical taper threads GB/T 9112 steel pipe flange type and parameters GB/T 9124 steel pipe flanges technical conditions GB/T 9969 Industrial Products Manual General GB/T 12220 common valve logo GB/T 12225 common valve copper alloy castings technical conditions GB/T 12230 general valve stainless steel castings technical conditions GB/T 13927 industrial valve pressure test GB/T 20878 stainless steel and heat-resistant steel grades and chemical composition GB/T 21873 rubber seal to the drain pipe and sewer pipe interface seal material specifications JB/T 308 valve model preparation methods JB/T 7928 general valve supply requirements

3 Terms and definitions

The following terms and definitions apply to this document.

Waterhammer for building water hammer absorbers waterhammerarrestorforwatersupplysystemofbuildings Water barriers are dampened by a sealed buffer plenum to prevent water mains and facilities from being damaged by water hammer.

Cushioning pressure chamber cushioningairpressurechamber According to the different absorber structure, are defined as.