Flanges are commonly used components in large pipeline projects, but many people are unfamiliar with what a flange is. So what exactly is a flange? Let's take a look!

Flanges, gaskets, and fasteners are collectively referred to as flange joints. Flange joints are widely used components in engineering and are essential components in piping design and installation. In application, flanges are not only frequently used in pipeline construction but also play a very important role in industrial, water supply and drainage systems, ventilation systems, and automatic control systems.

Flat sealing surfaces are suitable for low-pressure and non-toxic media. The sealing surface of the groove is suitable for explosive, flammable, toxic media, and high pressure. Gaskets are rings that cause plastic deformation and have a certain material strength.

This may be more standard but is less known. For example, when there are long-distance pipelines, a part of the pipeline needs to be connected to the overall pipeline, installing valves on that pipeline, observing mirrors, retractors, etc. It is welded with electric welding, but it cannot be disassembled during future maintenance. Therefore, many of these pipelines choose flange connections for future maintenance and replacement. The flange end is connected to the pipeline by welding or other methods, and the two opposing flanges are fixed together with fasteners (bolts) to form a complete pipeline; this is basically how valves are connected.

Flange heat treatment process: heating the metal, insulating and cooling, results in different properties of the metal. The performance of the same flange pipe also differs after heating. For example, heating and cooling flange pipes yield stainless steel. Flange pipes have excellent performance, and the heating process of stainless steel flange pipes is one of the important parameters in the heat treatment process.

In flange heat treatment, the annealing cooling rate is usually slow, the normalizing cooling rate is faster, and the quenching cooling rate is even faster. However, due to the different types of steel, there are also different requirements. After the metal is heated, when the workpiece is exposed to air, flange metal parts are often oxidized, and decarburization has a significant adverse effect on the surface performance of heat-treated steel parts. Flange pipe metals usually must be in a controlled or protective atmosphere. Neutral salt vacuum heating can also be protected by coating or packaging.

In addition, the heating temperature of the flange is one of the important process parameters in the heat treatment process. The selection and control of the heating temperature are the main issues to ensure the quality of heat treatment, and the heating temperature varies according to the metal material and heat treatment purpose. Generally, by heating above the phase transition temperature, the metal heat treatment heating methods for high-temperature flange pipes are diverse, with the earliest using carbon as the heat source, then using liquid and gas fuels, and now many manufacturers use electrical applications, which are easy to control and do not cause environmental pollution.