how to made carbon steel pipe flange
How to made carbon steel pipe flange?
How to choose made flange material?
The material has black carbon steel and stainless steel. The mechanical properties of raw materials include mechanical properties at room temperature and high temperature, such as strength index, plasticity index, impact toughness, hardness, fracture toughness, permanent strength, creep limit, fatigue properties, stress corrosion resistance, etc. The different uses are specified separately and are stated in the technical requirements for raw materials. Some mechanical properties of large-size raw materials are low, so pay attention to the design of materials.
Raw material smelting process
Ultra-high-strength steel, titanium alloy and high-temperature alloy are produced by vacuum self-consumption remelting process, and titanium alloy and high-temperature alloy require no less than secondary vacuum self-consumption remelting. The alloy structural steel and the non-induced heat-resistant steel are produced by an electric arc furnace, an electric arc furnace electric slag remelting double process or other better smelting methods. Aluminum alloys are usually smelted by flame furnaces, electric resistance furnaces and induction furnaces, and high-quality aluminum alloys require a series of technological measures to strictly control the impurity content and diversify the heat treatment state of the materials.
Different type flange:
Standard: ASTM A105,ASTM A420
SIZI:SCH160XXS, SCH 120,SHC160 and so on
Type: slip on flange, weld neck flange, blind flange
Made:steel forged,low temperatute
Different welding type:
Socket welding:Socket welding generally inserts the pipe into the flange for welding. The socket weld cannot be used for radiographic inspection. Socket welding for magnetic powder or penetration testing
Butt welding:Butt welding uses a butt welding flange to weld the pipe to the butt joint. The weld can be radiographically flawed. It is recommended to use the butt welding flange for high weld joint inspection requirements. The quality after welding is good, but the detection method is relatively strict. Butt welding to do radiographic inspection
Flange flow chart
①Receiving inspection of raw material. It is the first compulsory chain to guarantee good quality. The testing items refer to chemical composition, mechanical capacity and metallographic analysis.
② Cutting raw material. Correctly and strictly controlling cutting size and proportion can ensure moderate cost.
③ Heating. It is a very important step for flange quality. It is the necessary to record the heating temperature in details to avoid overheating. Overheating will destroy the structure of the metal and mechanical properties.
④ Forging. Forging process is divided into free forging and die forging. The forging time and strength of flange is different for different pressure class.
⑤ Heat treatment. The purpose of heat treatment is to eliminate the stress inside of flange so that the density is more evenly. Carefully recording the temperature of heat treatment and cooling time are the keys.
⑥ Forging blank inspection. Choosing some blank samples to test the chemical composition and mechanical property again to ensure all items are qualified.
⑦ Machining. In the machining process, the inspection is carried out along with the processing, so that to guarantee each part of flange is qualified.
⑧ Finishing checking. Finished products will be checked 100% before delivery to ensure the cargos are perfect.
The whole production chains are all very important, so the datas of each production step of flange must be recorded in details according to ISO request. It is the guarantee for good quality.
