GB/T 32270-2024Pressure piping code—Power piping (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules for standardization documents" Drafting.

This document replaces GB/T 32270-2015 "Pressure Piping Specification - Power Piping". Compared with GB/T 32270-2015, except for the structural adjustment in addition to the integration and editorial changes, the main technical changes are as follows:

--- Added some terms and definitions (see 3.28, 3.29, 3.30, 3.31, 3.32);

--- Deleted some terms and definitions (see 3.21 and 3.22 of the 2015 edition);

--- Deleted pipeline classification (see Chapter 4 of the 2015 edition);

--- Changed the use regulations of straight seam electric fusion welded steel pipes and corresponding pipe fittings (see 4.3.1.2, 5.3.1.2 of the 2015 edition);

--- Changed the relevant provisions of pipe support and hanger materials (see 4.3.2, 5.3.2 of the 2015 edition);

--- Added relevant provisions for the use of chromium-containing steel materials (see 4.3.4.1);

--- Deleted the "GD category" requirements for design pressure (6.1.1.2, 6.1.1.3 of the 2015 edition);

--- Changed the selection requirements for pipeline components other than those listed in the standards (see 5.2.1.3, 6.2.1.3 of the 2015 edition);

--- Increased the minimum wall thickness requirements for welded pipe fittings (see 5.2.1.6);

--- Added material selection requirements for oil and gas pipelines within the power plant (see 5.2.2.5~5.2.2.7);

--- Changed the type and size standards of flange covers (see 5.2.7.2, 6.2.7.2 of the 2015 edition);

--- Changed the valve type selection provisions (see 5.2.8.5, 6.2.8.5 of the 2015 edition);

--- Changed the flange type selection provisions (see 5.2.9.1, 6.2.9.1 of the 2015 edition);

--- Changed the selection requirements of compensators (see 5.2.10.1, 6.2.10.1 of the 2015 edition);

--- Added the requirement that "the thickness of the pipeline components should not be less than the minimum wall thickness of the straight pipe" (see 5.3.1.2);

--- Changed the requirements for the value of the pipe outer diameter in the calculation formula for the minimum wall thickness of the pipe (see 5.3.2.1, 6.3.2.1 of the 2015 edition);

--- Changed the branch connection form applicable to the area reinforcement method (see 5.3.4.2, 6.3.4.2 of the 2015 edition);

--- Added branch pipe connection forms applicable to the pressure area method (see 5.3.4.3);

--- Added the calculation formula for the elliptical shape coefficient of the ellipsoidal head and the calculation of the wall thickness (see 5.3.7.1);

--- Deleted the value diagram of the correction factor K when the elliptical shape factor of the ellipsoidal head is 2 (see Figure 9 of the 2015 edition);

--- Added pipeline conditions for pipeline stress calculation and accidental loads to be taken into account (see 5.4.1);

--- Added the calculation method of the thrust or torque of the pipeline on the equipment or end point (see 5.4.3);

--- Added the load distribution principle of the upper and lower supports of vertical pipes (see 5.5.2.3);

--- Added the requirements for reserved expansion gaps for limit devices and guide devices (see 5.5.3.4~5.5.3.6);

--- Added access permit requirements for production and installation units (see 6.1.3);

--- Changed the requirements for acceptance of materials before fabrication or installation (see 6.2.1, 7.2.1 of the 2015 edition);

--- Added the welder qualification requirements for stamping and signing the quality certificate (see 6.2.2.3, 6.4.1.3);

--- Added requirements for ordering welding materials (see 6.4.2.2);

--- Changed the requirements for the number of weld repairs (see 6.4.8.3, 7.4.8.3 of the 2015 edition);

--- Added measurement requirements for temperature measuring instruments (see 6.5.1.5);

--- Changed some residual heat methods (see 6.5.3.1, 7.5.3.1 of the 2015 edition);

--- Increased insulation width requirements (see 6.6.5.1);

--- Added requirements for pipeline installation, pipeline cleaning, purging and cleaning (see 6.7, 6.8);

--- Changed some requirements for progressive inspection (see 7.2.1, 8.1.3 of the 2015 edition);

--- Changed the batching principle for sampling inspection (see 7.2.2.1.2, 8.2.1.2 of the 2015 edition);

--- Changed the requirements for the metallographic structure of weld metal and pressure test substitution (see 7.2.2.6, 7.4.2, 8.3.5.1, 2015 edition 8.5.2);

--- Added requirements for non-destructive testing methods (see 7.2.3.3);

--- Changed the dimension of chloride ion concentration in the test water for austenitic stainless steel (see 7.4.4, 8.5.4 of the 2015 edition);

--- Changed the basic provisions for pipeline insulation and pipeline corrosion protection (see 9.1.1, 9.2.1, 10.1.1, 10.2.1 of the 2015 edition);

--- Changes to the insulation materials, moisture-proof layer materials, insulation layer materials, and insulation layer thickness calculation regulations (see 9.1.2.1~9.1.2.3, 9.1.3.2, 10.1.2.1~10.1.2.3, 10.1.3.2 of the 2015 edition);

--- Changed the atmospheric corrosivity and soil corrosivity classification standards (see 9.2.2.1, 9.2.2.2, 10.2.2.1, 2015 edition 10.2.2.2);

--- Changed the provisions for the selection of anti-corrosion coatings (see 9.2.3.2, 10.2.3.2 of the 2015 edition);

--- Changed the design requirements of the anti-corrosion layer system and the coating thickness requirements (see 9.2.4.1, 9.2.4.3, 10.2.4.1, 2015 edition 10.2.4.3);

--- Changed the inspection and acceptance regulations for anti-corrosion projects (see 9.2.4.5, 10.2.4.5 of the 2015 edition);

--- Changed the allowable stress of some materials (see Appendix A, Appendix A of the 2015 edition);

--- Increased the allowable stress of 10Cr9MoW2VNbBN material and straight seam electric fusion welded steel pipe (see A.1);

--- The flexibility coefficient and stress increase factor have been changed (see Appendix C, Appendix C of the 2015 edition);

--- Added piping layout (see Appendix D).

1 Scope

This document specifies the materials, design, production, installation, inspection, testing, installation and maintenance of steam and water pipelines within the boundary of a thermal power plant: Basic requirements for full protection, thermal insulation and corrosion prevention.

Other pressure pipelines within the boundary of thermal power plants shall comply with GB/T 20801 (all parts).

This document does not apply to:

a) Boiler main body pipeline;

b) Nuclear power plant piping;

c) Heating, ventilation and air conditioning ducts and ducts with non-circular cross-sections;

d) Pipes for various towers, building structures, storage tanks, mechanical equipment and instruments;

e) Non-metallic pipes.

The boundaries between the pipelines specified in this document and the pipelines within the boiler body are shown in Figures 1 and 2.

Description of index symbols:

---Boiler main pipes shall be managed in accordance with TSG11;

--- Boiler external piping and joints (i.e. steam, water piping and joints specified in Chapter 1), boiler-wide piping design in accordance with TSG11 take into account the calculations referred to in this document;

--- Non-boiler external pipes and joints.