Some basic options for pipeline flanges

Pipe flange is a bridge used to establish a connection between two pipes. It can be used to dismantle the piping system, temporary or mobile installation, transition between dissimilar materials and to connect in an environment that is not conducive to cementing.

Flanges are relatively simple mechanical connectors, especially in high-pressure pipeline applications. It is recognized in the industry as reliable and extremely cost-effective. Compared with other mechanical connectors, flanges have a very high torque carrying capacity. This is an important function of systems that experience pipeline flow through changes in temperature and pressure (such as deep water pipelines). The flange can be designed to meet various application requirements, such as high temperature and corrosion resistance.

Mode of operation

The flange of the pipeline is flush with the pipeline to which it is connected. The holes in the surface are mechanically connected by bolts, collars, adhesives or welds.

Welding connects materials by melting the workpiece and adding filler materials. For the firm, high-pressure connection of materials, welding is often the most effective method of flange connection. Most pipeline flanges are designed to be welded to the pipeline.

Brazing is used to melt material by melting filler metal, which solidifies to act as a connecting meson. This method will not melt the workpiece and cause thermal deformation, thus achieving tight tolerances and clean joints.

Many connection methods have distinctive characteristics, and there are other more important considerations for the selection of pipe flanges. Factors consumers should consider are the physical specifications, types, materials and performance characteristics of the flange that are most suitable for the application.

Physical specifications

First, the flange must be suitable for the pipe it is designed for. The physical specifications of pipe flanges include size and design shape.

Flange size

The physical size should be specified in order to adjust the flange size reasonably.

The outer diameter (OD) is the distance between two opposite edges of the flange face. Thickness refers to the thickness of the outer edge of the connection, excluding the flange portion of the fixed pipe.

The bolt circle diameter is the length from the center of the bolt hole to the center of the opposite hole.

The pipe size is the corresponding pipe size of the pipe flange and is usually made according to recognized standards. It is specified by two numbers without dimensions, namely the nominal pipe size (NPS) and the schedule (SCH).

The nominal diameter is the inner diameter of the flange connector. When manufacturing and ordering pipe connectors, the hole diameter of the pipe fitting should match the hole diameter of the mating pipe.