Various materials will be re-inspected in the factory according to different manufacturing methods
Pressure vessel steel mainly includes carbon steel, low alloy steel, high alloy steel, low temperature steel, medium temperature steel and composite steel plate. The re-inspection method should be different according to whether the material needs heat treatment to restore performance during the manufacturing process.
① The material does not undergo the thermal process of metallographic phase transformation during the manufacturing process of the pressure vessel, and does not need to undergo the final recovery performance heat treatment, which is a general manufacturing process. The raw materials used in this process are carried out according to the requirements of the purchased parts.
②When the material undergoes the thermal process of metallographic phase transformation and the heat treatment for restoring performance during the manufacturing process of the pressure vessel, a sample should be prepared from the heat-treated sample blank provided by the steel plant for mechanical performance re-inspection. If necessary, heat-treated sample blanks can be directly cut from raw materials, and then sampled for inspection after simulating the thermal process of the manufacturing process. The sample thickness is the thickness of the steel plate. The length and width of the sample should not be less than 3 times the thickness of the steel plate. The axis of the sample should be located at 1/4 of the thickness from the surface of the sample, and the distance between the sample and each side of the sample. Not less than the thickness of the sample blank, and the inspection items and quantity should meet the requirements of the drawings or technical conditions.
③The re-inspection of imported materials should be conducted in accordance with the test methods, acceptance requirements, sample form, size, and processing requirements specified by the corresponding specifications and standards of the material producing country, and the technical requirements shall not be lower than the technical indicators of the corresponding domestic materials. The foreign brand materials produced by domestic material manufacturing units shall also be re-inspected according to this principle.
Incoming acceptance of raw materials
The principle of factory acceptance
①The pressure vessel manufacturing unit shall establish the acceptance control procedures for raw materials (plates, pipes, welding materials, forgings, bars and other pressure components) and purchased parts.
②The quality, specifications and markings of the materials used for pressure vessels shall comply with the requirements of the corresponding material standards and ordering technical agreements specified in the design documents.
③The manufacturer of special steel plates for pressure vessels shall obtain corresponding special equipment manufacturing licenses.
④The pressure vessel manufacturer shall be responsible for the authenticity and consistency of the materials and material quality certificates obtained for pressure vessels.
⑤Overseas brand materials should be materials that are permitted to be used in the current standards and specifications of overseas pressure vessels and have been used overseas, and their scope of use should comply with the regulations of the corresponding overseas product standards.
Steel plates, copper pipes, steel forgings, steel rods enter the factory for acceptance
Strict management of pressure vessel pressure components and material quality are important measures to ensure the quality of pressure vessel products. For this reason, pressure vessel manufacturers should formulate corresponding acceptance systems to prevent unqualified raw materials from flowing into the production process.
① When the raw materials enter the factory, the material inspector should review the material quality certificate according to the drawing requirements, procurement technical documents, material standards, etc. The content of the quality certificate should be complete and complete. Regarding material grades, specifications, quantities, supply status, inspection items and data , Implementation of standards, etc., and the material quality control person in charge will give the material inspection number.
a. The material quality certificate should be the original steel plant quality certificate. It should be stamped with the steel plant quality inspection seal or the copy of the inspection official seal of the material supplier and the effective seal of the handler;
b. After the material quality certificate is inspected and meets the requirements, the consistency between the quality certificate and the actual product should be inspected, that is, the batch number, material number, specification, supply status and material mark of the actual furnace should be consistent with the quality certificate;
c. Special materials for pressure vessels subject to manufacturing license. The quality certificate and the mark on the material should also include the manufacturing license mark and license number.
② After the material quality certificate has passed the examination, the material inspector must check the consistency of the material quality certificate and the actual product. The physical product identification is clear, and the brand, specification, batch number, supply status, etc. are consistent with the quality certificate.
③The raw materials need to be checked:
a. Appearance quality. The surface of the material has no defects such as cracks, bubbles, scars, folds and inclusions.
b. Material specifications and geometric dimensions.
c. All raw materials that need to be re-inspected shall be re-inspected according to project requirements.
④ For raw materials with no quality certificate, no original mark on the material, inconsistent quality certificate with the raw material, or unqualified re-inspection, the manufacturer shall refuse to accept the storage.
⑤ When there are doubts about the materials of the main pressure components, the person in charge of the material quality control decides the content of the re-inspection.
⑥ The raw materials that have passed the experience should be placed in the material qualified area according to the grades and specifications. Stainless steel and carbon steel should be placed separately. The material custodian should transplant the mark on the material according to the regulations. The mark is confirmed and verified by the inspector.
⑦Stainless steel and non-ferrous metal materials should be set up in special storage areas and should not be placed in the open air.
⑧ Make a record of the acceptance of materials in storage.
⑨ The raw material report that has passed the above inspection should be reviewed and confirmed by the person in charge of material quality control.
Acceptance of welding consumables
The quality of the welded joints between the pressure components of the pressure vessel product is a relatively weak link in terms of the safety of the pressure vessel. Although the factors that affect the quality of welded joints are more complicated, the primary factor in order to ensure its quality is to ensure that the welding materials are qualified. Welding materials are not used well or mixed in construction.
① The pressure vessel manufacturer shall establish and strictly implement the welding material acceptance, re-inspection, storage, drying, distribution and recycling system.
② Welding materials used to manufacture pressure components of pressure vessels should ensure that the mechanical properties of the weld metal are higher than or equal to the limit specified by the base material.
③After the welding materials enter the factory, the purchaser will review whether the items and data of the welding material certificate conform to relevant standards, ordering technical agreements, technical conditions and special requirements together with the person in charge of material quality control. After passing the inspection, the person in charge of material quality control shall give the welding material inspection number.
④ Welding materials must have quality certificates and clear and firm marks, and the packaging of welding materials must be intact.
⑤After the welding material quality certificate has passed the inspection, the purchaser and the material custodian shall verify the batch number, weight, quantity, etc. of the welding material and the quality certificate, and the contents shall be unified.
⑥ Where special re-inspection item requirements are required, re-inspection should be carried out as required.
⑦The welding materials that have passed the inspection and re-inspection should be placed in the welding material warehouse that meets the management requirements, and the material should be marked by the keeper in an obvious position.
⑧The welding material warehouse for storing welding materials must meet the following conditions:
a. Welding material first and second storehouses should be equipped with a hygrometer and a dehumidification device. The temperature in the warehouse should be above 5℃; the relative humidity should be below 60%.
b. The custodian should record the temperature and humidity in the welding material warehouse once a day in the morning and afternoon.
c. It is strictly forbidden to place harmful media such as oil and water in the welding material warehouse.
d. The distribution of welding materials should be distributed first in the advanced warehouse to prevent the welding materials from being stored in the warehouse for too long.
e. Special welding consumables should be kept by a dedicated person, and a special area should be set up for storage to prevent mixing.
Acceptance of purchased parts (safety accessories, standard parts, etc.)
Other metal materials used for pressure components of pressure vessels are accepted according to the acceptance principle of raw materials, but safety accessories for pressure vessels (safety valves, bursting disc devices, emergency shut-off valves, pressure gauges, liquid level gauges, temperature measuring instruments, etc.) ) And other auxiliary parts (standard parts, gaskets, etc.) should also be checked and accepted according to the requirements of technical conditions and corresponding standards.
(1) Safety accessories
① After the safety accessories enter the factory, the purchaser, together with the custodians and inspectors, will inspect the content, model, specification, scope of application, materials, conformity standards, and compliance with the ordering technical agreement of the quality certificate.
② After the quality certificate is qualified, the mark, label and external dimensions of the actual product shall be verified and inspected according to the quality certificate.
③ For the safety accessories that need to be verified, the verification work will be carried out after the above inspection work is qualified, and the verification work will be kept after passing the verification.
(2) Other auxiliary materials
① For standard parts for pressure vessels, if there are special technical requirements, there should be a quality certificate. The content of the quality certificate meets the technical requirements of the project content, and the mark is clear, and there is a database of rejected persons with unclear marks.
② The standard parts with performance level requirements must have the marks required by the corresponding national standards, and the unclear marks are refused to be put into the warehouse.
Incoming acceptance of outsourcing parts
The outsourcing processing of pressure components of pressure vessels is generally carried out by the pressure vessel manufacturing unit due to insufficient processing capacity or production time requirements. Outsourcing processing is generally processed with materials. Therefore, when outsourcing processing, you should sign an agreement with the outsourcing unit to clarify the processing content, requirements, qualification standards and respective responsibilities, or hand over the construction drawings and processing technical requirements together with the blanks. Processing by the cooperating unit, after processing the outsourcing parts and entering the factory, the inspection and acceptance shall be carried out according to the following principles.
(1) Acceptance of stamping parts and hot work parts
Stamping parts and hot-worked parts refer to parts that are formed by outsourcing units only by pressure processing or other hot-work methods.
① Whether it is consistent with the content of the drawing, technical agreement or processing technical requirements.
② Inspect the appearance quality and size of stamping parts and hot work parts according to drawings.
③Whether the material mark is the original mark of the unit during the inspection (all the subcontracted parts with marking requirements should require the subcontractor to retain the original mark), when the subcontractor cannot keep the original mark, the mark transplantation should be required, and Confirmed by the inspection personnel of the outsourcing processing unit to prevent the outsourcing unit from mixing.
(2) Incoming acceptance of heat treatment outsourcing parts
① After the heat-treated parts enter the factory, the outsourcing personnel and the inspectors will check the heat treatment automatic recording curve and the heat treatment process as follows: whether the entering temperature, heating rate, holding time and temperature, cooling rate, and exit temperature are consistent. At the same time, the heat treatment automatic recording curve record paper should also record the project number, part number, name, quantity, name and quantity of the furnace test plate, the signature of the operator and the inspector, the heat treatment date and the heat treatment unit inspection stamp. And other content.
②Inspect the physical object for deformation during the heat treatment process and whether the sealing surface is protected, etc.
③The heat treatment is followed by the furnace heat treatment and so on.
(3) Incoming inspection and acceptance of outsourcing parts for machining
① After the mechanical processing outsourcing parts enter the factory, the outsourcing personnel and the inspectors will inspect the surface processing accuracy, processing dimensions and tolerances of the physical objects in accordance with the drawings and processing technical requirements.
②Whether the material mark is transplanted clearly.
Acceptance of other metal materials
Acceptance of cast iron materials
Because cast iron is a brittle material with low tensile strength and its quality is greatly affected by casting reasons, the application restrictions on cast iron materials are: it must not be used to contain extremely toxic, highly toxic or hazardous media, and the design pressure is greater than or The pressure components of the explosive medium pressure vessel equal to 0.15MPa shall not be used for the pressure components of the shell-and-tube waste heat boiler. In addition, the allowable cast iron materials for pressure vessels are specified in the "Consolidation Regulations", and should:
① After the iron castings enter the factory, the purchasing personnel and the material quality control person shall inspect the guaranteed items, data, delivery status, grades, etc. in the quality certificate according to the drawings and technical agreements, and the mechanical properties shall meet the requirements of the corresponding national standards.
②The purchaser shall inspect the physical size together with the inspector, and there shall be no shrinkage, slag inclusion, looseness and other defects that affect the strength and processing.
Acceptance of non-ferrous metal materials for pressure vessels
①The acceptance inspection of non-ferrous metal materials (aluminum, iron, copper, nickel and their alloys) used for pressure vessels shall be carried out according to the acceptance inspection principle of raw materials. For special projects, the quality certificate shall be verified according to the requirements of the order technical agreement, and the physical object shall be re-inspected.
② Non-ferrous metals used in pressure vessels should be stored in a special place, and a strict storage system should be established, which should be stored separately from carbon steel and low alloy steel.
③When non-ferrous metal materials such as iron and iron alloys, nickel and nickel alloys, copper and copper alloys, aluminum and aluminum alloys, tantalum, zirconium, niobium and their alloys are used in pressure components of pressure vessels, their design pressure, design temperature, and heat treatment state It shall comply with the relevant provisions of the "Consolidation Regulations".
Acceptance of composite steel plate materials for pressure vessels
①The acceptance inspection of clad steel plates for pressure vessels shall be carried out in accordance with the requirements of the above-mentioned raw materials.
②The clad steel plate used for pressure vessels shall comply with the relevant regulations of the "Consolidation Regulations".
a. The shear strength of the composite interface of stainless steel-steel, nickel-steel, iron-steel, copper-steel clad plate and the use state of the base material should meet the requirements of the "Consolidation Regulations".
b. Carbon steel and low-alloy steel base materials (including steel plates and steel forgings) shall be impacted in accordance with the provisions of the base material standards
test.
Acceptance of overseas grade materials
① The technical requirements of foreign brand materials shall not be lower than those of similar domestic materials (such as phosphorus and sulfur content, sampling location, sampling direction and impact energy index of impact samples, elongation after fracture, etc.).
②The material quality certificate and material mark shall comply with the provisions of the "Consolidation Regulations".
③ Review the incoming materials and material quality certificates, and conduct a confirmatory re-inspection of the chemical composition and mechanical properties of the materials.
④The material used for welding structural pressure components, the welding procedure qualification shall be carried out before the first use.
⑤Steel materials with a standard tensile strength lower limit greater than or equal to 540MPa, and low-alloy steel materials with a design temperature lower than -40℃ shall pass the technical review in accordance with the "Consolidation Regulations".
⑥ The overseas grade materials manufactured in China shall meet the requirements of ① ~ ⑤ above, and shall also pass the technical review in accordance with the requirements of the "Consolidation Regulations".
Re-inspection of materials
General requirements for reinspection
① When the following situations occur, the materials shall be re-inspected:
a. For the manufacture of four-stage forgings for pressure vessels of the vessel category;
b. The main pressure component materials for which the authenticity of the quality certificate cannot be determined or the performance and chemical composition are doubtful;
c. Overseas brand materials used to manufacture pressure components;
d. Austenitic stainless steel open plate used to manufacture main pressure components (a set of retest samples should be intercepted at both ends of the open plate);
e. The design drawings require re-inspection materials.
②Re-inspection content and quantity:
a. Surface quality and material mark of steel plate;
b. The mechanical properties of austenitic stainless steel open plates should be retested according to the batch number, and the chemical composition of other materials should be retested according to the heat number and the mechanical properties should be retested according to the batch number;
c. If the ultrasonic inspection guarantee is not provided, the ultrasonic inspection re-inspection shall be carried out in accordance with the requirements of the "Consolidation Regulations".
③The results of the material reinspection should meet the requirements of the corresponding material standards or design drawings.
④The low-temperature container welding rod should be re-inspected for the moisture content of the coating or the diffusible hydrogen content of the deposited metal according to the batch, and the inspection method should be in accordance with the corresponding electrode standard or technical requirements.
