Flange Profile and Purpose

Flanges are very practical for the pipe system that needs dismantle, and the Heat Treatment of Flange is also important. Here are a brief introduction about flange and its heat treatment.

Flanges and gaskets, fasteners collectively known as flange joints. Flange joints are widely in engineering design. It is an essential part of piping design and valve, and it is also a common part in engineering such as industry, heat, water supply and drainage, heating, ventilating, and control.

Forging flange sealing surface has three types:

Flat Face (FF), it is suitable for the low pressure, the medium non-toxic situation. Female and Malel Face (FMF), applies to the slightly high pressure occasion. Tongue and Groove Face(T and G). It is suitable for the flammable, explosive, the poisonous medium and the high pressure situation. GASKET is a kind of ring which can produce plastic deformation and have a certain strength of material.

For example, there is a long distance pipeline,the whole pipeline need to be connected by each pipe, also installed valve, sight glass and so on, then weld it up. But it is not convenient for repair or maintenance later because of its non-removability. So most of these pipes will be uses flange joints, To facilitate the maintenance and replacement.

The flange is weld connection to the pipe or in other ways. And then fix two relative flanges with fasteners (bolts), which form a complete pipe. Pipes and valves, sight glass are basically the same way to connect.

Heat Treatment of Flange

Heat treatment is necessary for Stainless Steel Fittings, Carbon Steel Fittings and Alloy Steel Fittings, and their treatment way are different. Metal performance will have different changes after process of heating, insulation, cooling, so as same flanges. Such as stainless steel flange superior performance, which get through the heating cooling on flange, At the same time, it is one of the important parameters in the heat treatment process.

The flange is in the process of heat treatment, the general annealing cooling speed is the slowest, the normalizing cooling speed is quicker, quenching cooling speed is faster. Flange are mutually connected and uninterrupted in the process. When heating, the workpiece connects to the air so oxidation often occurs. Decarbonization (the reducing of steel carbon content), The fittings have a very adverse impact after heat treatment. Flange and fitting usually should be controllable atmosphere or protective atmosphere. Coating or packaging methods can protect heating molten salts and in vacuum.

In addition, the heating temperature of the flange is one of the important technological parameters in heat treatment process, and controlling the heating temperature is the main problem to ensure the heat treatment quality. It is generally heated to a phase change temperature above to obtain high temperature tissue. Heating is one of the important processes of heat treatment. There are many heating methods for flange and fittings,firstly use charcoal and coal as heat source, and then apply liquid and gaseous fuel. Now a lot of manufacturers are using electrical applications, so easy to control, and no environmental pollution. Using these heat sources can be directly heating, or molten salt or metal, floating particles for indirect heating. At the same time, the performance of flange is different from the process of cooling, the main control cooling speed.