A flange is a disc-shaped part that is most commonly seen in pipeline engineering, and flanges are always used in pairs. In pipeline engineering, flanges are mainly used for the connection of pipelines. For the pipelines that need to be connected, a flange plate is installed on each pipeline. Threaded flanges can be used for low-pressure pipelines, and welded flanges are used for pipelines with a pressure of more than 4 kilograms. A sealing gasket is placed between the two flange plates, and then they are tightened with bolts.
Flanges with different pressures have different thicknesses and use different bolts.
When pumps and valves are connected to pipelines, the local parts of these equipment are also made into corresponding flange shapes, which is also called flange connection.
Any connecting part that uses bolts to connect two planes around the perimeter and is closed at the same time is generally called a "flange". For example, the connection of ventilation pipelines, this kind of part can be called a "flange-type part".

The end cover (Cover) is a rear cover installed behind the casing of motors and other equipment, commonly known as the "end cover". The end cover generally refers to the covers at both ends of the motor whose axial dimension is larger than the radial dimension. Its main function is to determine the spatial position of the shaft of the rotor. Of course, it needs to be matched with different types of bearings. It is connected to the casing that fixes the motor stator through the end cover to ensure the gap between the rotor and the stator. Generally, it is manufactured by casting process, and for small motors, it can also be formed by stamping of sheet metal.

The quality of the end cover (Cover) directly affects the quality of the motor. Therefore, we first need to understand what the criteria for a good or bad end cover are. A good end cover mainly comes from its core part - the brush plate, whose function is to drive the rotation of the rotor. This part is the most critical part. So, how should we measure its quality? It mainly has the following criteria:

Why are there these criteria?
Because as long as there is a problem in one link of the brush plate, it will affect the quality of the motor. If the brush is too high, it will touch the varistor; if it is too low, it will touch the white washer; (seen in the rotor) if it is too short, it will not touch the rotor, which will make the rotor unable to operate; if the brush is split, it will make the current unstable; of course, it cannot be bent either, as it will make the current abnormal. It should be added that the brush plate of the end cover is very brittle. If you are not careful, the brush will be split, bent, and other phenomena may occur. Please pay attention!
As one of the very important mechanical parts, the end cover is widely used. The main working surfaces of this part are the left and right end faces and the outer circular surface of the left end face. Its general functions are: