Flange (Flange), also known as flange flange disk or flange flange. Flange is a part of the mutual articulation between shaft and shaft, used for the articulation between pipe ends; also used in the import and export of equipment flange, used for the articulation between two devices, such as reducer flange. Flange joint or flange joint, refers to the flange, gasket and bolt three articulated with each other as a set of combined sealing structure of the detachable articulation. The pipe flange refers to the pipe installation with the flange, used in equipment refers to the import and export flange of the equipment. There are holes on the flange, and the bolts make the two flanges tightly connected. Gasket seal between the flange. Flange is divided into threaded articulation (fillet articulation) flange, welding flange and clamp flange. Flanges are used in pairs, low-pressure pipelines can be used wire connection flange, four kilograms of pressure above the use of welding flange. Between the two flanges plus gasket, and then fastened with bolts. Different pressure flange thickness is different, and they use different bolts. Pumps and valves, in connection with the pipeline, these parts of the equipment, but also made of the corresponding flange shape, also known as the flange connection. But all in the two planes around the use of bolts articulated at the same time blocked articulation parts, commonly known as "flange", such as the articulation of ventilation ducts, this type of parts can be called "flange parts". But this articulation is only a part of the equipment, such as flange and pump articulation, it is not good to call the pump "flange parts". Smaller than the valve, such as the valve, can be called "flange parts".

　　Precision planetary gearbox flange, for the motor and reducer connection, as well as the reducer and other equipment between the connection.

　　Classification methods

　　1, according to the chemical industry (HG) industry specifications: integral flange (IF), threaded flange (Th), plate flat welding flange (PL), necked butt welding flange (WN), necked flat welding flange (SO), socket welding flange (SW), butt welding ring loose flange (PJ/SE), flat welding ring loose flange (PJ/RJ), lined flange cover (BL (S)), flange cover (BL).

　　2, according to the petrochemical (SH) industry specifications: threaded flange (PT), butt welding flange (WN), flat welding flange (SO), socket welding flange (SW), loose flange (LJ), flange cover (not table note).

　　3, according to the machinery (JB) industry specifications: the whole flange, butt welding flange, plate flat welding flange, butt welding ring plate loose flange, flat welding ring plate loose flange, flanged ring plate loose flange, flange cover.

　　4, according to the national (GB) specifications: overall flange, threaded flange, butt welding flange, necked flat welding flange, necked socket welding flange, butt welding ring necked loose flange, plate type flat welding flange, butt welding ring plate type loose flange, flat welding ring plate type loose flange, flanged ring plate type loose flange, flange cover.