Production Process of Insulation Joint

Insulated joint is a general term for pipeline joints that meet the sealing performance, strength performance, and insulation performance requirements for buried steel pipelines. It includes components, insulation board, packing, sealing ring, short tube, etc.

Chinese name for insulation joint

Size specifications DN15~DN1200

Pressure rating PN1.0~PN40Mpa

Manufacturing standard SY/T0516-2008

Insulated joint is an upgraded product based on the problems existing in the use of insulated flanges. It is an essential and important pressure component in the cathodic protection system of steel pipelines and is widely used in the cathodic protection system of steel pipelines.

Insulation strength: 2500V 50Hz, no breakdown or arcing for 1 minute; Insulation resistance: DC 1000V resistance ≥ 6M Ω; Hydraulic test pressure: 1.5 times the design pressure; Airtight test pressure: equivalent to the design pressure; Non destructive testing: 100% radiographic testing of all butt joints according to JB4730-94, and 100% magnetic particle testing of other pressure bearing welds; Groove: Adopting API5L standard.

A high-strength rail insulation joint is formed by placing rail end insulation components at the ends of two connected rails, with groove type insulation plates clamped on both sides of the joint, and two reinforced fish tail plates installed in the grooves of the insulation plates. Then, high-strength bolts are inserted into the reserved holes of the joint and tightened. The first type of insulation board is a mesh glass cloth groove type insulation board, with the first, third, fifth, and seventh layers being paste like insulation adhesive, the second and sixth layers being mesh glass cloth, and the fourth layer being thickened glass cloth; The second type of insulation board is an electric heating plate slot type insulation board, with the first, third, fifth, and seventh layers being insulating adhesive films, the second and sixth layers being glass cloth, and the fourth layer being perforated electric heating plates.

The integral insulation joint consists of the following parts: upper and lower pipes, sleeves, insulation components, seals, and insulation coatings. A double sealed structure with insulation performance is formed by sandwiching insulation and sealing components between the upper and lower pipe mating faces of the insulation joint. The sleeve adopts two forms of groove welding or direct welding with the upper conduit, which firmly wraps the insulation and upper and lower pipes inside, forming a "sealed container", thus ensuring good insulation effect and greatly improving the pressure bearing capacity of the insulation structure.