【導(dǎo)讀】ofthisRegulation.Regulation.approvalinadvance.

　　

【正文】 n steel factory shall submit verification views, 3 TECHNICAL SUPER VISION REGULATION FOR SAFETY OF STEAM BOILERS 17 trialmanufacture results and stability of volume production steel to the SSA of MOL to place them on file. Clause 29. The following requirements shall be met when boiler pressure parts are made of steels with foreign designation: (1) The steel designation shall be one listed in the foreign boiler steel standard or the designation whose chemical position, mechanical properties, welding performance are similar to those of domestic permitted boiler steels and listed in steel standard or mature boiler steel designation. (2) Acceptance inspection shall be performed inaccordance with the technical standard and the technical condition prescribed in order contract. Compared with domestic standards, if an inspection item is in short, the inspection item in short shall be added whenever necessary, only after the inspection is qualified can the steel be used. (3)Before the steel is used for the first time, welding procedure qualification and forming performance test shall be carried out, only after the test results are satisfied, can the steel be used. (4)Boiler strength calculations shall be conducted employing the performance data prescribed in the technical standard and the technical condition of the steel. (5)Consent from SSA of MOL shall be obtained for the steel not listed in standard and the electric resistance welded boiler tube listed in standard. Clause 30. When the steel manufacturer produces foreign designation steel, the production and acceptance inspection shall be carried out in full accordance with the foreign standard. Production appraisal shall be carried out before volume production. 3 TECHNICAL SUPER VISION REGULATION FOR SAFETY OF STEAM BOILERS 18 Clause 31. For the main steel products in boiler services, such as plate, tube and welding consumables, receiving acceptance inspection shall be made by the boiler manufactory according to relevant rules. Only the acceptance inspection is satisfied, can the steel products be used. For the steel products for boilers with a rated steam pressure less than or equal to , retest can be exempted when the original quality certificates are plete and the materials are marked pletely and clearly. For the materials with stable quality and with proved product safety quality by a SSA of MOL, retest can be exempted. Other wise, it stall not be exempted. Clause 32. Rules of management for storage, maintenance and use of materials shall be established by the boiler manufactory. Markings for steel products for boiler pressure parts shall be available. Shift of markings shall be made for identification, before the steel plate for pressure part is cut off. Clause 33. Rules of management for storing, drying, distribution returning and reuse shall be established by the user for welding consumables for boiler pressure parts. Chapter 4 Structure Clause 34. The structure of boiler shall conform to following basic requirements。 (1)In operation each part shall be able to expand unrestrainedly in the 3 TECHNICAL SUPER VISION REGULATION FOR SAFETY OF STEAM BOILERS 19 direction preset in design。 (2)Normal water circulation in each circulating lop shall be guaranteed, all heating surfaces shall be cooled reliably。 (3)Sufficient strength shall be available for each pressure part。 (4)Compound stress and stress concentration shall be avoided or reduced to a minimum in consideration of pressure part structure and arrangement of opening and welded seams。 (5)The structure of the watercooled furnace shall be able to carry sufficient loading。 (6)The brickwork shall be of good gastightness。 (7)Loadbearing structural ponent shall be of sufficient strength, rigidity, stability and corrosionresistance when the design load is applied。 (8)The structure shall be easy for installation, operation, inspection, repair, internal and external cleaning. (9)For pulverized coal fired boiler, the structure and arrangement of furnace and burner shall be adapted to design coal type, and protected against furnace slaging or cooking. Clause 35. Expansion indicators on drum and header shall be provided for boilers with rated steam pressure and above. The expansion center for boiler proper determined in design shall be fixed up for pendant boiler. Clause 36. The wall thickness used for shell cylinder shall not be less than 6mm at all times for watertube boiler and it shall not be less than 12mm when heating tube and drum are connected by expanding. 3 TECHNICAL SUPER VISION REGULATION FOR SAFETY OF STEAM BOILERS 20 Clause 37. The wall theckness used for shell cylinder shall not be less than 6mm for shelltype boiler with inside diameter of boiler shell greater than 1000mm, and it shall not be less than 4mm when the inside diameter does not exceed 1000mm. Clause 38. The inside diameter of the internal furnace of shell boiler shall not exceed 1800mm, and the wall thickness used for internal furnace shall not be less than 8mm nor greater than 22mm。 When the inside diameter is 400mm or lesser, the thickness used shall not be less than 6mm. The plate thickness of the reverse bustion chamber of horizontal internally busted boiler shall not be less than 10mm nor greater than 35mm. Clause fixing manner between header and inner tube sleeve and between spray tube and header shall be able to guarantee relative expansion and avoid resonance, and the structure and arrangement shall be easy for inspection and repair. Clause 40. The minimum safe water level of watertube boiler drum shall be able to guarantee downers to be supplied with water reliably. The lowest sage water level of shell boiler shall be 100mm higher than the fire line. The lowe