1 Scope
This standard specifies the basic requirements of materials, design, fabrication, erection, inspection, test, safety protection, insulation and corrosion resistance of piping with steam, water as well as flammable, explosive, toxic and corrosive liquid or gas as the medium within the battery limit of thermal power plants. Reference shall be made to GB/T 20801 for piping with flammable, explosive, toxic and corrosive liquid or gas as medium.
This standard is not applicable to the following piping:
a) boiler body piping;
b) nuclear power plant piping;
c) piping for heating, ventilation and air conditioning as well as those with non-circular cross section;
d) piping for various towers, building frames, storage vessels, mechanical equipment and instruments.
This standard does not include the material requirements of nonmetal piping.
See Figures 1 and 2 for the boundary between the piping specified in this standard and those within the boiler body.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB 150-2011 (all parts) Pressure vessel
GB/T 229 Metallic materials - Charpy pendulum impact test method
GB/T 231.1 Metallic materials - Brinell hardness test - Part 1: Test method
GB/T 700-2006 Carbon structural steels
GB 713-2014 Steel plates for boilers and pressure vessels
GB/T 1048 Pipework components - Definition and selection of PN
GB 3087 Seamless steel tubes for low and medium pressure boiler
GB/T 3091 Welded steel pipes for low pressure liquid transmission
GB/T 3274 Hot-rolled plates, sheets and strips of carbon structural steels and high strength low alloy structural steels
GB/T 4622.2-2008 Dimensions for spiral wound gaskets for pipe flanges
GB 5310 Seamless steel tubes and pipes for high pressure boiler
GB/T 7233 (all parts) Steel castings - Ultrasonic examination
GB/T 8163 Seamless steel pipes for liquid service
GB 8624 Classification for burning behavior of building materials and products
GB/T 8923 (all parts) Preparation of steel substrates before application of paints and related products - Visual assessment of surface cleanliness
GB/T 9115 Butt-welding steel pipe flange
GB/T 9116 Hubbed slip-on-welding steel pipe flanges
GB/T 9119 Slip-on-welding plate steel pipe flanges
GB/T 9123 Steel pipe blank flanges
GB/T 9124 Specification for steel pipe flanges
GB/T 9125 Fasteners for steel pipe flange joints
GB/T 12228 General purpose industrial valves - Specification of carbon steel forgings
GB/T 12229 General purpose industrial valves - Specification of carbon steel castings
GB/T 12230 General purpose industrial valves - Specification of stainless steel castings
GB/T 12241-2005 Safety valves - General requirements
GB/T 12242-2005 Performance test code - Pressure relief devices
GB/T 12243-2005 Spring loaded safety valves
GB/T 12777 General specification for metal bellows expansion joints
GB/T 13298-1991 Inspection methods of microstructure for metals
GB/T 13927-2008 Industrial valves - Pressure testing
GB/T 15957-1995 Corrosivity classification of atmospheric environment
GB/T 16253 Steel castings for pressure purposes
GB/T 17116 (all parts) Pipe supports and hangers
GB/T 17186 Calculating method for strength steel pipe flanged joint
GB/T 17394 Metallic materials - Leeb hardness test
GB/T 20801-2006 (all parts) Pressure piping code - Industrial piping
GB 50016 Code for fire protection design of buildings
GB 50021 Code for investigation of geotechnical engineering
GB 50126 Code for construction of industrial equipment and pipeline insulation engineering
GB 50185 Code for acceptance of construction quality of industrial equipment and pipeline insulation engineering
GB 50229 Code for design of fire protection for fossil fuel power plants and substations
GB 50264 Code for design of industrial equipment and pipeline insulation engineering
GB 50764-2012 Design code of power of piping for power plant
DL/T 438-2009 The technical supervision codes for metal in fossil-fuel power plant
DL/T 515-2004 Pipe bends for power station
DL/T 868-2014 The code of welding procedure qualification
DL/T 869-2012 The code of welding for power plant
DL/T 991-2006 Spectral analysis guideline of metal for electrical power equipment
DL/T 5072-2007 Code for designing insulation and painting of fossil fuel power plant
JB/T 3223 Welding material quality management specifications
JB/T 4730 (all parts) Nondestructive testing of pressure equipments
JB/T 5263 Specification for steel casting for power station valves
JB/T 6439 Methods of magnetic examination for valves
JB/T 6440 Methods of radiographic examination for steel castings valves
JB/T 6902 Methods for liquid penetrant examination of valves
JB/T 7927 Valve cast steel visual quality requirements
JB/T 9625 Specification for pressure retaining casting of biller pipe fittings
JB/T 9626 Specification for biller forging
JB/T 10087 Specifications for steel casting of steam turbines for pressure purposes
NB/T 47008 Carbon and alloy steel forgings for pressure equipment
NB/T 47009 Low alloy steel forgings for low temperature pressure equipment
NB/T 47010 Stainless and heat-resisting steel forgings for pressure equipments
NB/T 47014 Welding procedure qualification for pressure equipment
SY/T 5037 Submerged arc-welded steel pipe for common fluid service pipeline
SY/T 5038 Longitudinal seam HFW steel pipe for common fluid service pipeline
TSG D0001 Pressure pipe safety technology supervision regulation for industrial pressure pipe
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3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
piping
piping that consists of pipe components, pipe supports and hangers, etc., which is used to transport, distribute, mix, separate, discharge, measure or control fluid flow
3.2
piping system
a group of piping formed by connecting one or more piping divided according to fluid and design conditions
3.3
piping component
components used to connect or assemble into piping, including pipe, pipe fitting, flange, gasket, fastener, valve, filter mesh and compensator
3.4
pipe or tube
piping component with circular cross section for conveying fluid
3.5
pipe fitting
a category of piping component, including bend or elbow, tee, branch, reducer and seal head
3.6
piping assembly
assembly composed of such pipes, pipe fittings, elbows and flanges as are separately numbered according to piping design
3.7
manufacture
production process of products such as piping component and piping supports and hangers
3.8
fabrication
process of connecting pipe fittings and pipes into piping assembly through working procedures such as cutting, groove preparation, bending, forming, welding, heat treatment, etc. in a shop or in the field before piping erection
3.9
erection
process of putting a piping system in place completely according to the regulations of piping design
3.10
test
a method for confirming the quality characteristics of products stipulated jointly by the owner and the manufacturing, fabricating and erection units according to the standards or regulations, including hydraulic test, air tightness test, etc.
3.11
verification
process of document confirmation of the received piping components and supports and hangers by the power piping manufacturing unit or erection unit
3.12
receiving acceptance
process of confirmation of the received piping components and supports and hangers by the power piping manufacturing unit or erection unit through verification and/or inspection
3.13
branch connection
structure leading branch from the main pipe, including integrally reinforced tee fittings and branch connection without reinforced welded structures
3.14
liquid collecting pocket (drain leg)
device for collecting condensed water set at the low point of gas or steam piping
3.15
sway brace
device for controlling low-frequency and high-amplitude sloshing or high-frequency and low-amplitude vibration of piping
3.16
snubber
device for bearing seismic load or impact load of piping, controlling high-speed vibration displacement of piping system, and allowing piping system to expand and contract freely with the change of temperature
3.17
stress intensification factor
ratio of the maximum bending stress produced by bending pipe, elbow, reducer and tee fitting under the action of bending moment to that produced by straight pipe bearing the same bending moment, or ratio of the fatigue strength of straight pipe to that of bending pipe, elbow, reducer and tee fitting under the action of the same alternating bending moment
3.18
cold spring
elastic deformation applied to the piping in advance when erecting the piping to produce the expected initial displacement and stress, thereby reduce the stress in initial hot state as well as the acting force and moment of the pipe end in initial hot state
3.19
flexibility
ability of the piping to absorb displacement deformation caused by thermal expansion, cold contraction and others through its own deformation
3.20
hot displacement
change of position of the piping system at the supporting and hanging point between cold and hot states
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Grading of piping
5 Materials
6 Design and calculation
7 Fabrication and erection
8 Inspections and tests
9 Safety protection
10 Insulation and anti-corrosion
Annex A (Normative) Allowable stress of materials
Annex B (Informative) Physical properties of commonly used materials
Annex C (Normative) Flexibility factors and stress intensification factors
Annex D (Informative) Common data for fabrication and erection
Annex E (Normative) Assembly deviations for piping prefabrication
Annex F (Normative) Calculations for safety relief devices
