Flange connections involve securing two pipes, fittings, or equipment to separate flange discs first, then inserting a flange gasket between the two flanges and fastening them together with bolts to complete the connection. Some fittings and equipment come with a flange disc already attached, which also falls under flange connections. Flange connections are an essential method for pipeline construction.
Flanged connections can be categorized by type of connection as: flat welding flange, socket welding flange, blind flange, threaded flange, and flange cover, necked socket welding ring gasket.
Socket flange, slip-on flange with flat welding ring, ring joint face flange and flange cover, large diameter flat flange, large diameter high neck flange, Lapped blind flange, weld neck slip-on flange, etc.
Flat welding flanges are suitable for steel pipe connections with nominal pressures not exceeding 2.5 MPa. The sealing surfaces of flat welding flanges can be made in three types: smooth, concave-convex, and tenon-slot. Smooth flat welding flanges are used for...
Usage. Commonly used in milder medium conditions, such as low-pressure non-purified compressed air, low-pressure recirculating water.
The neck height of the flanged flat welding flange is lower, which improves the rigidity and load-bearing capacity of the flange. Compared to the welding neck flange, it requires more welding work and higher consumption of welding rods.High-pressure andBend repeatedly and temperature fluctuations, but easy for on-site installation, can omit the process of welding seam knocking, and is well-received.
A flat weld ring loose flanged flange is a movable flange plate, commonly used with water supply and drainage fittings (often seen on expansion joints). When the manufacturer ships, each end of the expansion joint comes with a flange, which is directly connected to pipelines and equipment in the project with bolts. The general purpose of using a flat weld ring loose flanged flange is to save materials; its structure is divided into two parts: the pipe section connects to the pipeline at one end and is flanged at the other, while the flange plate is slipped over the flange. The flange plate is made of low-grade material, while the pipe section uses the same material as the pipeline, achieving the goal of material conservation.
Loose fit flange with welding ring, loose fit neck flange with welding ring, loose fit flat ring flange, loose fit inverted flat flange. Additionally, to meet the locking requirements after installation, flanges with threaded rods and holes are available, which prevent bolts from loosening during vibration. Some flange bolts with no threads are made slender, known as slender rod flange bolts. These bolts are beneficial for connections subjected to variable forces. High-strength bolts are used in steel structures, with larger heads and varying sizes. Hot-dip galvanized round steel produces an alloy layer through the reaction of molten metal with the iron substrate.
