Butt welding flange is a kind of flange. The flange is a part that connects the pipe to the pipe and is connected to the pipe end. There are holes in the flange, and the bolts make the two flanges tightly connected. Butt weld flanges and their gaskets and fasteners are collectively referred to as flange joints. Flange joints are an essential component in equipment and equipment components, and are also indispensable parts in piping design and pipe fittings.
Butt welding flange is not easy to be deformed, sealed well, widely used, suitable for pipelines with high pressure or temperature fluctuations or high temperature, high pressure and low temperature pipelines. The advantage is that the price is relatively cheap, the nominal pressure does not exceed 2.5MPa; also used for conveying price On the pipeline of expensive, flammable and explosive medium, the nominal pressure is around PN16MPa. The welding flange connection is easy to use and can withstand large pressures. The welding flange pads are made of different materials according to different grades of pressure. From low-pressure asbestos pads, high-pressure asbestos pads to metal mats.
Butt welding flange
Production process of butt welding flange:
1. Whether the annealing temperature reaches the specified temperature. The welding flange treatment is generally a solution heat treatment, which is commonly called “annealing”, and the temperature range is 1040~1120 °C (Japanese standard). You can also observe through the observation hole of the annealing furnace. The flanged pipe fittings in the annealing zone should be in an incandescent state, but there is no softening and sagging.
2. The welding flange is used to process the water vapor in the casting furnace. On the one hand, check whether the material of the furnace body is dry. When the furnace is installed for the first time, the material of the furnace body must be dried. Second, whether the flanged pipe fittings entering the furnace have excessive water stains. If there are holes on the flange pipe fittings, do not leak water. Go in, or else destroy the atmosphere of the stove.
3. The furnace body sealability. The soldering flange bright annealing furnace should be closed and isolated from the outside air; if hydrogen is used as the shielding gas, only one exhaust port is open (used to ignite the discharged hydrogen). The inspection method can be applied to the gaps of the joints of the annealing furnace with soapy water to see if it runs. The most easy place to run the gas is the place where the annealing furnace enters the pipe and the place where the pipe is discharged. The sealing ring in this place is particularly easy to wear. Always check frequently.
4. Protect the gas pressure. In order to prevent micro-leakage on the welding flange, the protective gas in the furnace should maintain a certain positive pressure. If it is hydrogen shielding gas, it generally requires more than 20kBar.
5. The annealing atmosphere. For the welding flange, pure hydrogen is generally used as the annealing atmosphere, and the purity of the atmosphere is preferably 99.99% or more. If another part of the atmosphere is an inert gas, the purity can be lower, but it must not contain too much oxygen or water vapor.
Source: China Butt Welding Flanges Manufacturer – Yaang Pipe Industry Co., Limited (www.yaang.com)