From the mechanical engineering point of view to accept a piece of equipment, accurately according to the equipment manufacturing drawings to correspond to each detail, standardized acceptance! Acceptance is generally according to specifications and technical agreements.
I have a certain equipment acceptance criteria, learn from it
Equipment acceptance criteria?
Note: The container data to be accepted include general drawings, product quality certificate, which includes the supervision and inspection certificate of the Special Inspection Institute, the acceptance of raw materials and quality certificates, manufacturing and inspection process records, hydrostatic test records, nondestructive testing report is basically the capacitance of the regulations on those said. Mainly on the gauge There are three types of pressure vessels and low-temperature manufacturing plant to provide the use of units container strength calculations. If necessary, but also to provide installation instructions.
For the arrival of the equipment should be compared with the equipment drawings and equipment related technical requirements or technical agreement, the special requirements of the parts of the key inspection.
Equipment arrival and installation inspection standards
I. Vertical or horizontal container type equipment, the overall in place installation quality inspection?
(I), the acceptance of the arrival of equipment?
1, check the equipment technical documents?
1.1 check whether the equipment has as-built drawings, pressure vessel product quality supervision and inspection certificate and product quality certificate.
1.2 Product quality certificate should include: product certification, container characteristics, the chemical composition and mechanical properties of the main parts and materials, container heat treatment status and forbidden welding and other special instructions, non-destructive testing results, welding quality inspection results, pressure test and air tightness test results, and design drawings do not match the project.
1.3 Comparison of as-built drawings and product quality certificates, check the equipment body and the main components are consistent with the design.
1.4 check whether each pipe port is complete with paired flange, bolts, gaskets.
1.5 Check whether the equipment body is installed on the equipment nameplate. The nameplate should include: the name of the manufacturing unit and manufacturing license number, the name of the pressure vessel and product number, design pressure, temperature and medium, maximum working pressure and maximum allowable working pressure, pressure vessel category and supervision and inspection mark, the net weight of the pressure vessel and the date of manufacture, the test pressure.?
1.6 Check whether there is a packing list, according to the as-built drawings and packing list inventory acceptance of the following items: count the number of boxes, box number and check the packaging; check the name, model and specifications of the equipment; check the specifications of the receiver, the orientation and the number of; check the specifications of the equipment, spare parts, accessories, size, type and quantity.
Note: All technical documents must be collected and stored, which is part of the equipment file, the pressure vessel certification also need this information
2, check the equipment body?
2.1 check the surface quality of the equipment body: no obvious damage to the surface of the equipment and uneven, no obvious distortion of the receiver, flange and other weldments, flange sealing surface is not damaged, the fixture should be cleaned of welding scars.
2.2 The equipment body is painted and anticorrosive according to the regulations, and the quality is qualified. Meet the drawings, technical requirements or technical agreement requirements.
2.3 equipment weld inspection: no cross welds, splicing seams should be arranged and staggered in accordance with the provisions of the pipe openings should avoid welds.
The weld surface shall not bite (depth ≤ 0.5mm, length ≤ 10% of the weld length and ≤ 100mm), cracks, failure to weld, failure to fuse, surface porosity, arc pits, failure to fill and slag visible to the naked eye and other defects.
The weld and the base material should have a smooth transition;
The height of the weld corner of the fillet or lap weld should be equal to the thickness of the thinner part;
The residual height of the weld is less than 4mm.
2.4 equipment body straight, no bending, twisting.
2.5 equipment to open the lid to check: internal components are complete such as: feed distribution pipe, export anti-vortex device, broken foam net installation requirements; weld misalignment <3mm;
Internal components support ring level: diameter less than or equal to φ1600 ≤ 3mm, diameter less than or equal to φ3200 ≤ 4mm;
Internal components installation level: diameter less than or equal to φ1600 ≤ 3mm, diameter less than or equal to φ3200 ≤ 4mm;
Internal components mounting level: diameter less than or equal to φ 1600≤3mm, diameter less than or equal to φ3200≤5mm;
Stainless steel inner member surface for pickling passivation;
No debris in the device, each opening is smooth.
(B), container installation quality inspection
1, pad iron installation: not loose, good contact, after alignment, position welding fixed (between the pad iron), each group of pad iron not more than four, exposed uniformly (10-30mm), lap length of not less than 3/4 of the whole length.
2, foot bolt installation: foot bolt nuts and washers are complete, uniform fastening, bolt threads without damage and exposed nut 2-3 buckles, leakage threads should be coated with antirust grease.
3, horizontal container sliding support installation: sliding end of the support plate of the waist-shaped holes and the location of the foot bolt should meet the expansion and contraction of the equipment under the conditions of the support plate and the base plate should be able to slide (no sliding obstacles on the surface and coated with lubricant). After the equipment piping is finished, loosen the foot bolt to 0.5-1mm gap.?
4, horizontal container installation level check: axial level ≤ L/1000 (L: equipment length), radial level ≤ 2D/1000 (D: equipment diameter). Measured by level meter.
5, vertical equipment verticality check: vertical equipment verticality ≤ H/1000, and ≤ 30 (H: equipment height). Measured with a latitude and longitude meter.
6, need to be installed on-site inspection of internal components:
Internal components support ring level: diameter less than or equal to φ1600 ≤ 3mm,
diameter less than or equal to φ3200 ≤ 4mm;
Internal components installation level: diameter less than or equal to φ1600 ≤ 3mm,
diameter less than or equal to φ3200 ≤ 5mm; adjacent to the support ring ≤ H/1000 and ≤ 30 (H: equipment height). 5mm; spacing between adjacent support rings ±3mm, ±10mm between any two of the 20 layers; support beam straightness ≤L/1000, and ≤5mm;
The distance between the bottom of the descending plate and the upper surface of the receiving plate is ±3mm, and the distance between the vertical edge of the descending plate and the vertical edge of the receiving plate is +5mm, -3mm;
The overflow weir height deviation: ±1.5mm for D≤3m,
D＞3m, D＞3m. mm, ±3mm when D＞3m;
Levelness of the upper surface of overflow weir: 3mm when D≤1.5m, 4.5mm when 1.5m＜D≤2.5m, 6mm when D＞2.5m.
Checking quantity: 10% of the total number of layers to be checked, and not less than 5 layers, and all of them to be checked if there are fewer than 5 layers.
7, tower disk within the components of additional inspection items: tower disk, card, sealing gasket installation position is accurate, the tower disk lap uniform, no obvious concave and convex deformation, the bolts are complete, tight (15% of the tower disk spot check); floating valve is complete, no jamming and falling off phenomenon.
8, the internal components of the installation is completed before sealing the manhole check: no accumulation of dirt in the container, no residual tools and accessories, debris, etc.?
9, the external appurtenances of the installation check: liquid level meter, pressure gauge, thermometer installation direction is easy to observe; flange bolts are complete, tight, whether full buckle, gasket is right, flange surface is parallel.
10, in the manhole back to install before the manhole gasket and its bolt size must be measured and recorded in the equipment list.
11, record the specifications of each container level gauge.?
12, measurement of each safety valve gasket, bolt specifications, and recorded in the safety valve file.?
13, equipment grounding resistance must be less than 10Ω.?
14, pumping outlet with a screen to check the use of the screen mesh (mesh less than half of the minimum diameter of the magnetic ball), the pumping outlet opening is consistent with the drawings (to avoid excessive pressure drop in the bed) and whether it is tied firmly, to avoid leakage of the magnetic ball from the pumping outlet or the magnetic ball is stuck in the pumping outlet of the openings, seams.
15, there is a broken foam net to carefully check the thickness of the broken foam net is consistent with the requirements of the drawings and bundling, fixed firmly, to avoid being washed out in the operation of the pipeline blockage.
Two, the heat exchanger of the whole in place to install quality inspection?
(A) the acceptance of the arrival of equipment?
1, check the equipment technical documents?
1.1 Check whether there is a product certification;?
1.2 Check whether there is a product characteristics table, which should include the design pressure, test pressure, design temperature, working medium, test medium, heat transfer area, equipment weight, equipment category and special requirements;?
1.3 Check whether the product quality certificate, the book should include: the main pressurized components of the material's chemical composition, mechanical properties and standards for the re-examination of the re-examination of the project's value; non-destructive testing and welding quality inspection report (including more than two return to repair records); through the ball records; austenitic stainless steel equipment, intergranular corrosion test report; equipment, heat treatment report (including the time) -Temperature record curve); appearance and geometry inspection report; pressure test and tightness test report.
1.4 Check whether there is equipment manufacturing as-built drawings; (now in general after the design of the drawings, the manufacturer should be stamped on the drawings as-built);
1.5 Check whether there is a packing list, according to the as-built drawings and packing list counting and acceptance of the following items: counting the number of boxes, box number and check the packaging; check the name of the equipment, model and specifications; check the receiver's specifications, orientation and Quantity; check the specification size, model and quantity of equipment spare parts and accessories.
1.6 Check whether the nameplate of the equipment is installed on the body of the equipment.
Note: All technical documents must be collected and stored, which is part of the equipment file, the pressure vessel certification also requires this information
2, check the equipment body?
2.1 check the surface quality of the equipment body: no obvious damage to the surface of the equipment and uneven, no obvious distortion of the receiver, flange and other weldments, flange sealing surface is not damaged, the fixture should be cleaned of welding scars.
2.2 The equipment body is painted and anticorrosive according to the regulations, and the quality is qualified. Meet the drawings, technical requirements or technical agreement requirements.
2.3 equipment weld inspection:
No cross welds, spliced seams should be arranged and staggered according to the provisions of the pipe openings should avoid welds. Weld surface shall not bite (depth ≤ 0.5mm, length ≤ 10% of the length of the weld and ≤ 100mm), cracks, unwelded, unfused, surface porosity, arc pits, unfilled and slag visible to the naked eye and other defects. Weld and base material should be smooth transition; fillet weld or lap weld welding angle height should be equal to the thickness of the thinner parts. The remaining height of the weld <4mm.
2.4 The equipment body is straight, no bending, twisting.
2.5 heat exchanger tube bundle must be core and pressure test check.?
(2), heat exchanger installation quality inspection?
1, the installation of pad iron: not loose, good contact, after the positioning of the right welding fixed (between pad iron), each group of pad iron not more than four, exposed uniform (10-30mm), lap length of not less than 3/4 of the full length.
2, the installation of bolts: foot bolt nuts and washers are complete, uniform fastening, bolt threads without damage and exposure of the nut 2-3 buckles, leakage of threads should be coated with antirust fat.
3, heat exchanger sliding support installation: sliding end of the support plate of the waist-shaped holes and the location of the foot bolt should meet the equipment under the conditions of expansion and contraction, support plate and the base plate should be able to slide (no sliding obstacles on the surface and coated with lubricant). After the equipment piping is finished, loosen the foot bolt to 1-3mm gap.?
4, heat exchanger installation level check: axial level ≤ L/1000 (L: equipment length), radial level ≤ 2D/1000 (D: equipment diameter). Measured with a level meter.
5, heat exchanger tube bundle after coring (coring must be tube box under the pipe mouth must be capped to prevent debris from falling such as the tube), carefully check the tube bundle fixed tube plate expansion weld mouth is intact, the tube plate sealing surface, the floating head, the hook ring sealing surface whether there is damage. Whether there is any damage to the appearance of the pipe bundle, and whether there is any damage at the bend of the U-shaped pipe bundle. Is the position of the anti-punching plate installed correctly (when the tube bundle back to the installation, the same attention to the position of the anti-punching plate, can not block the outlet).?
6, pipe box sealing surface damage, whether the diverter plate angle weld is qualified (appearance check).?
7, shell both sides of the ** Lan and the big head cover sealing surface whether there is damage.?
8, measure the standard heat exchanger tube box, floating head, big head cover at the gasket, bolt specifications, and recorded in the heat exchanger ledger. Special attention should be paid to the material of the bolt to comply with the provisions: high temperature parts of the bolt must use alloy steel bolts (see the provisions of the following table), in the low-temperature wet hydrogen sulfide corrosive medium in the small floating head bolts can not be used in high-strength alloy bolts, can only be used in the 35 # / 25 # steel. General bolts and nuts are played on the material code, the code and the material of the corresponding relationship is as follows:?
Material code 1 2 3 4 5 6 7?
Material 25# 35# 45# or 40MnB, 40Cr 30CrMoA 35CrMoA 25Cr2MoVA stainless steel?
Bolts generally have a higher material grade than nuts.? Therefore, for the pipeline and equipment of the non-hydrogen critical system, the temperature is below 250℃ generally use carbon steel bolts and nuts, i.e. 35#/25#;?
For non-hydrogen critical system pipeline, equipment, temperature at 250 ℃ - 400 ℃ general selection of 35CrMoA / 30CrMoA; for hydrogen critical system pipeline, equipment, temperature at 200 ℃ below the general selection of carbon steel bolts and nuts, that is, 35 # / 25 #; for hydrogen critical system pipeline, equipment, temperature at 200 ℃ - 300 ℃ general selection of 35CrMoA / 30CrMoA. 35CrMoA/30CrMoA;?
For the pipelines and equipments of the pro-hydrogen system, 25Cr2MoVA/35CrMoA or 25Cr2MoVA/25Cr2MoVA is generally used for the temperature of 300℃-550℃;?
For the pro-hydrogen system of piping, equipment, temperature at 550 ℃ -700 ℃ generally use stainless steel bolts and nuts;
9, grounding resistance must be less than 10Ω.?
Three, air-cooled overall in place to install quality inspection?
(a) Acceptance of equipment arrival?
1, check whether the structural components, parts, air-cooled tube bundle, fan, motor, etc., quality certificates, product manuals, etc., the information will be taken back to the workshop, safekeeping. Meet the drawings, technical requirements or technical agreement requirements.
2, check whether there is a packing list, according to the as-built drawings and packing list inventory acceptance of the following: count the number of boxes, box number and check the packaging; check the name, model and specifications of the equipment; check the specifications of the receiver, the orientation and the number of; check the specifications of the equipment spare parts, accessories, size, type and quantity, in particular, the fan's belt and fan blade specification size.
3, equipment appearance check: finned tubes should not be broken, cracked, rolled edges, inverted and adjacent fins close together. No damage to the flange surface of the tube bundle; the weld surface of the tube box weld shall not bite the edge (depth ≤ 0.5mm, length ≤ 10% of the length of the weld and ≤ 100mm), cracks, unwelded, unfused, surface porosity, arc pits, unfilled and slag visible to the naked eye and other defects. Weld and base material should be smooth transition; fillet weld or lap weld welding angle height should be equal to the thickness of the thinner parts. The residual height of the weld <4mm.
4, check whether the motor, tube bundle, wind pipe on the nameplate is complete.
(2), air-cooled installation acceptance?
1, air-cooled tube bundle installation must be carried out before the hydrostatic test, the test pressure in strict accordance with the nameplate on the test pressure.
2, the frame is firmly connected, the air blower itself and the air box connected tightly, and all the bolts are tightened.
3, the frame, wind turbine wind box without mechanical damage and residual deformation, columns and beams without obvious skewing.
4, wind box wall plate on the connection weld should be tight, no leakage of welding, intermittent, burn through, joints disconnected and wrapped corners are not dense.
5, the verticality of the column shall not exceed 1/1000 of the total length of the column, and not more than 25mm.?
6, wind cylinder ellipticity: diameter of 2-3m ≤ 2.5mm; diameter of 3-5m ≤ 4mm.
7, wind cylinder flange surface parallelism: diameter of 2-3m ≤ 5mm; diameter of 3-5m ≤ 6mm.
8, wind cylinder wall and fan blade tip spacing deviation: diameter 2-3m for 3-8mm; diameter 3-5m for 4-12mm.
9, fan motor seat center position deviation ≤ ± 2mm.?
10, the level of pipe bundle does not exceed 1/1000 of the length of the bundle.?
11, the disk car flexible without lightness.?
12, fan test run check: whether the blade is smooth, there is no impact sound, the belt is not loose, fan vibration is not greater than 0.15mm, motor bearing temperature is not greater than 70 ℃
Four, process piping acceptance standards
1, the standards adopted
"Industrial Metal Piping Engineering Construction and Acceptance Specification" GB50235-97
Code for Construction and Acceptance of Welding Works for On-site Equipment and Industrial Pipelines GB50236-98
Code for Construction and Acceptance of Piping Works for Toxic and Combustible Media in Petrochemical Industry SH3501-2002
Non-destructive Testing of Pressure Vessels JB4730-94
1.1 Scope of Application
Industrial Metal Piping Engineering Construction and Acceptance Code GB50235-97
Applicable to industrial metal pipelines with design pressure not greater than 42Mp and design temperature not exceeding the permissible operating temperature of the material
Petrochemical toxic and flammable media pipeline engineering construction and acceptance code SH3501-2002
Applicable to pipeline engineering construction and acceptance code SH3501-2002
Applicable to industrial metal pipelines with design pressure of 400Pa ( Adiabatic pressure) ~ 42MP (gauge pressure), design temperature -196 ℃ ~ 850 ℃ toxic, combustible media just straight pipeline engineering construction and acceptance.
2, pipeline classification
Pipeline level Applicable range
SHA 1, the degree of toxicity of extremely hazardous media pipeline (except benzene pipeline)
2, the degree of toxicity of highly hazardous media propiononitrile, phosgene, carbon disulfide and hydrogen fluoride media pipeline
3, the design pressure of not less than or equal to 10.0 Mp to transport poisonous and combustible media pipeline
3, the design pressure is not equal to 10.0 Mp to transport, Combustible media pipeline
SHB 1, the degree of toxicity for extremely hazardous media benzene pipeline
2, the degree of toxicity for highly hazardous media pipeline (except acetonitrile, phosgene, carbon disulfide and hydrogen fluoride pipeline)
3, Class A, Class B combustible gases and liquefied hydrocarbons Class A A A, Class A B, Class A A combustible liquids pipeline media
SHC 1, Toxicity degree of moderate, mildly hazardous media pipeline
2, Class B, Class C combustible liquid media pipeline
SHD low-temperature pipeline design temperature below -29 ℃
3, pipeline components of the inspection
3.1 pipe, fittings, valves must have the manufacturer's quality certificate.
3.2 Pipe, pipe fittings should be used before the appearance of the inspection, the surface should meet the following requirements.
--No cracks, shrinkage, slag, folding, heavy skin and other defects.
--No more than the negative deviation of the wall thickness of rust, depression and mechanical damage.
--There is material marking.
3.3 Materials should be carefully checked the material and specification of the pipeline according to the design requirements before the material is used.
3.4 Pipe constituents and pipe supports shall be properly stored during construction, shall not be confused or damaged, and their color codes or markings shall be obvious and clear.
3.5 Pipes that cannot be installed temporarily shall be closed at the mouth.
3.6 Valve Inspection
3.6.1 Valve products used in the project, should be consistent with the design documents, "valve specification" requirements.
3.6.2 Valve quality certificate should be the following:
1, the manufacturer's name
2, valve name, model, specifications, nominal pressure
3, applicable media, temperature
4, the date of shipment
5, the product standard designation, the conclusion of the quality inspection
6, the manufacturer of inspection units and inspectors stamped. Unit and the seal of the inspector
3.6.3 The appearance of the valve quality should meet the following requirements:
1, the valve should be the manufacturer's nameplate, the nameplate should be marked: valve name, model, nominal pressure, nominal diameter, operating temperature, the name of the manufacturing plant;
2, the valve's shell should be marked with a nominal pressure, nominal diameter, the media flow direction and other markings;
2, the valve shell should be marked with a nominal pressure, nominal diameter, media flow direction and so on;
3, the valve should be marked with a nominal pressure, nominal diameter, media flow direction and other markings;
3, the valve body shall not be damaged, corrosion, lack of parts, dirty, off the nameplate, the color scale does not match, etc.;
4, the valve handle or handwheel should be operated flexibly and easily, without jamming phenomenon;
5, the valve should be intact at both ends of the temporary end cap, closed tightly, the valve body is free of debris;
3.6.4 the following pipeline valves, one by one to carry out the shell pressure test and sealing test. Test and sealing test. Unqualified, shall not be used.
1) delivery of toxic fluids, combustible fluids pipeline valves;
2) delivery of design pressure greater than or equal to 1MP, or design pressure less than or equal to 1MPa and design temperature greater than 186 ℃ non-combustible fluids, non-toxic fluids pipeline valves
3) delivery of design pressure design pressure is less than or equal to 1MPa and the design temperature is -29 ~ 186 ℃ non-combustible fluids, non-toxic fluid pipeline valves should be 10% from each batch, and not less than one for the shell pressure test and sealing test. When unqualified, should be doubled sampling, still unqualified, the batch of valves shall not be used.
3.6.5 Valve shell test pressure shall not be less than 1.5 times the nominal pressure, the test time shall not be less than 5min. to shell packing no leakage as qualified; sealing test to nominal pressure, to the valve valve sealing surface does not leak as qualified.
3.6.6 test qualified valves, drain the internal water in a timely manner, blow dry. In addition to the need to degrease the valve, the sealing surface should be coated with antirust oil, close the valve, closed the entrance and exit, make a clear mark.
4, pipe prefabrication processing
4.1 pipe prefabrication prefabrication according to prefabrication processing plan and meet the following requirements:
4.1.1 pipe prefabrication processing according to the site review and confirmation of the pipe section prefabrication plan. Prefabrication processing drawings should be labeled on-site welding location and adjustment margin;
4.1.2 Welds on-site welding should be easy to apply and inspect.
4.2 Each process in the process of pipe prefabrication should check its marking and marking transplantation.
4.3 Pipe cutting, beveling
4.4 Steel pipes with curvature exceeding the allowable deviation are straightened before processing. Carbon steel pipe can be cold or hot adjustment, stainless steel pipe should be cold adjustment.
4.5 Cold conditioning of steel pipes is carried out at room temperature, and pipes with a nominal diameter of not more than 50mm are straightened in the pipe straightening machine, and its compression mold should be in line with the outer diameter of the steel pipe.
4.6 Carbon steel pipe hot tuning should be heated to 800 ~ 1000 ℃, and then flat to the platform repeatedly rolled to make it visually straighten, can also use flame straightening method.
4.7 steel pipe under the material should be according to the size of the prefabricated processing map number material. Cutting should comply with the following provisions:
4.7.1, stainless steel pipe should be cut by mechanical or plasma method:
4.7.2, carbon steel pipe can be cut by flame, and the surface layer that affects the quality of welding must be removed.
4.8 Welding bevel processing of steel pipe should meet the following requirements:
4.8.1, carbon steel pipe, it is appropriate to use mechanical methods of processing, can also be used flame processing:
4.8.2, stainless steel pipe should be processed by mechanical methods. Stainless steel pipe if cut or repaired by grinding wheel, must use special grinding wheel sheet.
4.8.3, if the flame or plasma processing of steel pipe, must remove the surface layer affecting the quality of welding.
4.9 The wall thickness difference between the two sides of the welding bevel is greater than the following values, it should be processed according to the requirements of thinning.
4.9.1 The difference of inner wall of SHA grade pipe is 0.5mm or outer wall is 2mm;
4.9.2. The difference of inner wall of SHB and SHC grade pipe is 1mm or outer wall is 2㎜;
4.9.3. The difference of outer wall of the rest of pipes is 3mm.
4.10 The quality of bevel shall be as follows:
4.10.1 The surface shall be smooth, and there shall be no cracks, heavy skin, burrs, convex and concave indentation;
4.10.2. The slag, iron oxide and iron filings on the cutting surface shall be removed;
4.10.3. The deviation of the end face inclination shall be 1% of the outer diameter of the pipe, but shall not be more than 2㎜;
4.10.4. The size of the beveling and the angle shall be in line with the requirements.
4.11 Pipe pairing, pre-assembly
4.12 Pipe section pairing, the seat cushion is placed firmly, positioning is reliable, to prevent deformation in the welding process.
4.13 Pipe segment alignment should be checked for straightness, the allowable deviation is 1㎜/m, but the maximum cumulative deviation of the whole length shall not exceed 10mm.
4.14 Pipeline components are grouped together, use the inner diameter of the alignment device.
4.14.1 When the pipe sections are grouped together, the method of strong alignment or heating the pipe shall not be used to eliminate the defects such as excessive gap, wrong edge and different center of the interface end face. When these defects are found, the dimensions of adjacent or related pipe sections shall be checked, and then the defective areas shall be corrected and reworked.
4.15 pipeline instrumentation source components should be in accordance with the specified location of the first drill holes and then welded. Thermometer take source parts of the opening, shall not be chamfered inward.
4.16 pipeline pre-assembly, should be pipeline components for inspection and cleaning, with the following conditions before assembly:
4.16.1, the pipeline components of the material, specifications, models should be in line with the design requirements;
4.16.2, pipeline components inside and outside the surface of the soil, grease and other debris and so on has been cleaned up:
4.16.3, complete marking.
4.17 When the pipe is pre-assembled, the overall size and the size of each part and the adjustment margin should be checked, and their deviation should be in accordance with the following requirements:
4.17.1 The permissible deviation of the total length L in each direction is ±5㎜;
4.17.2 The spacing N, and the permissible deviation is ±1.5㎜;
4.17.3 The transversal deviation of the branch pipe and the main pipe c The allowable deviation is ±1.5mm;
4.17.4 The bolt holes adjacent to the flange face shall be installed across the center, and the allowable deviation of f is ±lmm;
4.17.5 The flange end face shall be vertical, and the allowable deviation of e is:
a. Not more than lmm when the nominal diameter is small boy or equal to 300mm;
b. Not more than 2mm when the nominal diameter is more than
4.18 The same wall thickness of the pipe pair, the inner wall flush, the amount of the wrong edge does not exceed the following provisions:
SHA grade pipe for 10% of the wall thickness, and not more than 0.5mm;?
SHB, SHC grade pipe inner wall difference of 1.0mm or outer wall difference of 2mm;
4.19 pipe prefabrication should be easy to transport and installation, the combination of parts should be sufficient stiffness and strength, otherwise there should be temporary reinforcing measures, and if necessary, should be marked out the location of the lifting rigging bundling points.
4.20 After the pipe section prefabrication is completed, it should be numbered and protected for safekeeping.
4.21 pipe support and hanger production, installation
4.21.1 pipe support and hanger should be installed in the pipeline according to the design of parts drawings and the amount of centralized processing, prefabricated in advance. Piping support, hanger type, processing size, material should meet the design requirements. Steel plate, steel section with mechanical cutting, cutting should be removed after the burr. Mechanical shear notch quality should meet the following requirements:
(1), shear line and the number of material line deviation is not more than 2 mm;
(2), the surface of the notch is not cracked;
(3), the end of the section steel shear slope is not more than 2 mm.
4.21.2 When thermal cutting is used, slag and splatter shall be removed, and the cutting quality shall meet the following requirements:
4.21.3 Bolt holes of pipe supports and hangers shall be processed by mechanical methods.
4.21.4 Pipe support, hanger ring or "U" type card with flat steel bending, the arc part should be smooth, the size should be consistent with the outside diameter of the pipe.
4.21.5 The working surface of the bottom plate of the bracket and the spring box of the spring support and hanger is smooth and clean. Slide or rolling bracket slide after processing, take protective measures to prevent scratches or bruises.
4.21.6 Piping support, hanger production and assembly, the deviation of the external dimensions shall not be greater than 3mm, and numbering and marking.
4.21.7 pipeline installation, timely adjustment and fixing support, hanger position is accurate, the installation is flat and firm, and pipe contact tight.
4.21.8 After installation, check the form and position of support and hanger one by one according to the design drawings.
4.21.9 Pipes without thermal displacement, the boom is installed vertically. There is thermal displacement of the pipeline, the hanging point is located in the opposite direction of the displacement, according to the displacement value of 1/2 offset installation.
5, pipe installation
6, welding process requirements and welding quality inspection
6.1 general process requirements
6.2 austenitic stainless steel welding
6.3 low-temperature steel welding
6.4 dissimilarity steel welding dissimilarity steel due to the physical and chemical properties of the larger differences in the dissimilarity of the weld metal than the same metal, complexity, the main welding in the application of welding. Metal is complex, the main problem in the welding is how to prevent cracking, decarburization and tissue inhomogeneity.
6.5 Welding Quality Inspection
6.5.1 Appearance Quality Requirements
The weld and the base material smooth transition, the surface should be free of cracks, pores, slag and other defects, the weld should not be lower than the base material surface, the residual height of the bevel does not exceed 1 + 0.1b (b is the maximum width of the bevel after the completion of the group) and does not exceed 3mm. low-temperature steel, stainless steel weld surface shall not exist. Edge biting phenomenon. Carbon steel weld edge depth of not more than 0.5mm, continuous length should not be greater than 100mm and the total cumulative length of not more than 10% of the length of the weld.
6.5.2 Internal quality requirements internal quality inspection in accordance with the design requirements and construction acceptance specification specified nondestructive testing standards.
6.5.3 Repair of surface defects
6.5.4 Rework of internal defects
The inspection program carries out appearance inspection and non-destructive testing.
7, piping system test and blowing
7.1 piping pressure test
1) piping system pressure test should be carried out according to the design requirements, after the piping installation is completed, nondestructive testing.
2) Before the pipeline pressure test, the corresponding information should be reviewed and confirmed by the construction unit, and jointly check the corresponding technical and quality conditions, qualified before the pressure test.
3) The pressure test is carried out with clean water, and the hydraulic test pressure is 1.5 times of the design pressure.
4) Pressure test should be carried out according to the design pressure of the pipeline section test, the design pressure of the same pipeline can be connected up at the same time for the pressure test.
5) test steps and requirements
Note: If there is a leak in the test process, shall not be repaired with pressure. Defects should be retested after elimination.
8, the project handover acceptance
8.1.1 before the handover of the project, the construction unit should be metal piping project installation quality inspection, confirmation, its quality should meet the standard requirements.
8.1.2 piping components of quality documents, re-examination reports should be complete.
8.1.3 quality inspection records should be complete and accurate.