1. clamping type: insert the square pipe into the pipe fitting, with protruding U-shaped grooves at both ends of the pipe fitting and built-in sealing rings, and use special pipe fitting tools to clamp and connect. Scope of application: DN (nominal diameter) ≤1mm, which can be installed in the open and applied in the dark.
2. compression type: insert the square pipe into the pipe mouth of the pipe fitting, fasten it with the nut, and compress the sleeve at the pipe mouth through the sealing ring with the screw force to play a sealing role, thus completing the connection of the square pipe. Scope of application: DN≤15mm, which can be applied openly and secretly.
3. welding type (socket or butt welding): conduct annular argon arc welding on the pipe fittings and fittings which are usually socket type, so as to play a sealing role and complete the connection of the fittings. Scope of application: for the pipelines of public buildings and large buildings, the DN is 15
mm
-1mm, and the DN is more than 1
mm, mostly by conventional butt welding; Indoor installation can be concealed, and outdoor burial can be done.
4. Quick-connect flange type: carry out annular argon arc welding on the flange and the matching parts, and use quick clamps to compress the gasket between the flanges to play a sealing role and complete the matching connection. Scope of application DN is 15
mm-1
mm, and it is used for pipelines of public buildings and large buildings.
5. Tapered thread type: annular argon arc welding is carried out on the external thread sleeve and the matching, and the internal thread pipe fittings are connected with tapered threads to play a sealing role, thus completing the matching connection. Scope of application DN is 65
mm-1
mm, which is used for pipelines in public buildings and large buildings, and can be used in harsh environments such as foundation subsidence, high temperature and high pressure.
6. Limit compression type: the square pipe adopts flanging or port welding ring, and the connection mode is articulated or semi-articulated. After the limit seal of rubber sealing ring is compressed by 2%-3%, it enters the metal sealing groove, and the limit seal is used to protect the sealing element. The joint can be made of copper or carbon steel. The application range DN is below 4
mm, and it is suitable for harsh environments such as foundation subsidence and various high temperatures and pressures.
7. Movable quick-connect flange: the traditional flange is changed into a movable flange, the square pipe end is turned over or welded, the ring mouth is embedded in a groove, and the sealing rubber piece is placed in the groove, and the sealing element is protected by limiting compression. The application range DN is below 4
mm, and it can be used as a buried pipe.
8. heat shrinkable pipe fittings: when connecting square pipes, on-site welding can be adopted. Because the welding point can't be handled in the construction site, heat-shrinkable pipe fittings are used as supplementary sealing, a rubber welding sleeve is put on the welding point of the pipeline, and then a special cross-linked polyethylene sleeve is put on it, which shrinks under the action of heat, so as to achieve shrinkage sealing. The applicable scope is pipes with DN below 4
mm.