Pressure ≤Mpa connection mode engineering size range DN system engineering
Pressure ≤Mpa Extrusion-Pressing Hexagon10 ~10.6 Flange-Pressing Convex 40 ~ 20010.6 Plum Club15 ~100/Kloc-0. 438+05~50 1.6 locking expansion type 50~250 1.6 double pressure single seal type10/.6 end face type 40~300 1.6 double pressure double seal type/kloc-. Kloc-0/.6 convex ring 15~32 1.6 butt welding type 125~300 1.6 snap ring type 15~32 1.6 groove type/kloc. 0 1.6- end type 15 ~ 32 1.6- flexible type15 ~1001.6-With the development of national economy and the improvement of people's living standards, thin-walled stainless steel water pipes and stainless steel pipe fittings have been developed.
Thin-walled stainless steel water pipe in China is a new type of pipe which came out at the end of 1990s. Stainless steel water pipes have a strong development momentum because of their safety, sanitation, high strength, good corrosion resistance, durability, long service life, maintenance-free and beautiful appearance, and have been widely used in building water supply and direct drinking water pipelines.
In 200 1 year, China Technology Market Management Promotion Center of the Ministry of Science and Technology issued the Notice on Popularizing and Applying Stainless Steel Pipe, Fitting and Special Technology for Medium and High Pressure Water Supply with Large Diameter-to-Wall Ratio and High Precision, which fully affirmed the thin-walled stainless steel pipe. It is considered that the popularization and application of this technology and products will be of great significance for improving the grade of modern buildings and improving and ensuring the water quality.
In July 2003 10, AQSIQ issued a series of standards, including GB/T 19228. 1 GB/T 19228.3, to promote the stainless steel card pipeline system.
On September 25th, 2003, China Engineering Construction Standardization Association issued CECS 153-2003 Technical Specification for Thin-walled Stainless Steel Pipe for Building Water Supply.
Because at present, in the field of thin-walled stainless steel water supply pipes and fittings, the main difference between related similar products lies in the different connection methods, so here are several representative connection methods of thin-walled stainless steel water supply pipes and fittings: convex connection, pressure connection, ring pressure connection and socket argon arc welding connection. "Card-convex connection method" is an improved method of crimping technology. Characterized in that the thin-walled stainless steel pipe end is rolled outwards (radially) from the inner wall by a special pipe expanding tool, and then the pipe is inserted into a pipe fitting with a socket frustum-shaped polytetrafluoroethylene sealing ring and a locking nut. When the lock nut is tightened, the flange ring pushes the compressed frustum-shaped PTFE sealing ring to seal. The design principle of its pipe fittings is basically the same as that of galvanized pipes in the past, which greatly avoids the complicated procedures in engineering design, budget and construction and is more conducive to popularization and application.
"Card-convex connection method" is an active connection method, which has the technical advantages of rapid assembly, convenience for future modification or maintenance, low technical requirements for construction personnel, stable connection, no influence from installation environment, improvement of construction efficiency, reduction of installation cost, no electricity, no sound and no open flame operation.
"Clamping convex thin-walled stainless steel pipe" and "Stainless steel clamping convex pipe fitting". The connection technology adopts: national invention patent: "a pipe joint for pipeline" (ZL01KLOC-0/05997.4), utility model patent: "a pipe fitting for pipeline" (ZL2004200559.2) and utility model patent: "pipe expander for pipeline connection" (ZL20042000
The basic composition of clamping pipe fittings is a special-shaped pipe joint with O-ring in the U-shaped groove at the end. When assembling. Insert the stainless steel water pipe into the pipe fitting and seal it with a special sealing tool. The pipe fittings and pipes in the sealing part are extruded into hexagons to form sufficient connection strength, and at the same time, the sealing effect is produced due to the compression deformation of the sealing ring. The cost of pipe fittings is low, which is suitable for popularization in civil market. Open-faced installation works are simple and the construction speed is fast. 1999, the first thin-walled stainless steel enterprise to enter China, adopted Japanese pressure welding technology in 1980s (pressure welding has no patent protection in China), and has now formulated national standards and standards. It absorbs mechanical connection methods such as ring pressing and clamping, draws lessons from the simple advantages of inserting copper pipes and plastic pipe fittings with sockets, and absorbs the traditional argon arc welding method of stainless steel.
Avoid the thorny problem of different service life of stainless steel and rubber ring (the latter will fail prematurely). The same service life of stainless steel material and building refers to stainless steel itself, and because rubber is used as sealing material in mechanical connection, the service life of rubber material and stainless steel material is definitely different, and the replacement of rubber material is inevitable. The welding type of groove socket is that stainless steel pipes and parts are directly dissolved and "dead" inside, and no other auxiliary materials are needed, so it can really be called maintenance-free and replacement-free;
Stainless steel pipes can be connected in many ways. Common pipe fittings include compression type, compression type, hinged type, push type, push thread type, socket welding type, hinged flange connection, welding type and series connection mode derived from the combination of welding and traditional connection. According to different principles, these connection methods have different application scopes, but most of them are convenient to install, firm and reliable. The materials of sealing ring or gasket used for connection are mostly silicone rubber, nitrile rubber and EPDM, which meet the requirements of national standards and eliminate the worries of users.