Loose flange
Loose flange with neck butt weld ring
Loose flange, butt weld ring, loose neck flange, butt weld ring loose plate flange, flat weld ring loose plate flange, plate flip over loose flange, and in order to meet the need of locking after the device, There are rods with holes, and these holes can prevent the bolts from loosening when they are vibrated. Some flange bolts without threaded polished rods should be made thinner, called thin rod flange bolts. This flange bolt is conducive to the connection of variable forces. There are special high-strength bolts on the steel structure, the head will be larger, and the size will also change. Hot-dip galvanized round steel makes the molten metal react with the iron matrix to produce an alloy layer.

Flat welding ring loose flange (PJ/SE)
The flat welding ring loose flange is a movable flange piece, which is generally matched with the water supply and drainage fittings (the most common on the expansion joint). When the factory leaves the factory, there is a flange on each end of the expansion joint, which is directly connected to the project. The pipelines and equipment are connected with bolts. The purpose of using flat welding ring loose flanges is generally to save materials. Its structure is divided into two parts. One end of the pipe is connected to the pipe, the other is made of flanging, and the flange part is sleeved on the flanging. The flange is made of low-grade materials, and the pipe part uses the same material as the pipe to save material.
Loose flange with flat welding ring:
1. Cost saving. When the pipe material is special and expensive, the cost of welding the flange of the same material is high.
2. It is inconvenient for welding or processing or requires high strength. Such as plastic pipes, glass steel pipes and the like.
3. Easy to construct. For example, it is not easy to align the flange bolt holes during connection or prevent the flange bolt holes of the equipment from being changed in the future.
Disadvantages of flat welding ring loose flange:
1. Low pressure.
2. Low strength at the welding ring (especially when the thickness is below 3mm)
Production standard of flat welded ring loose flange: