Views:2541 Author:Site Editor Publish Time: 2020-05-19 Origin:Site
When decorating and laying wires, most families use buried wiring. In this way, flame-retardant PVC pipes are used. Because the price of PVC pipes is five or six yuan per meter more expensive than ordinary pipes, many owners buy sets of pipe pipes that are ordinary thin plastic pipes. Once this kind of pipe is used, the wires will leak. , No fire protection. Many homes use a large amount of combustible materials such as wood and cloth as interior decoration materials. They are often used without fire protection, and close the unsightly power switch in the room with a cabinet or decorative frame. These are hidden fire safety hazards. The rigid polyvinyl chloride pipe for water supply is simply referred to as PVC-U water supply pipe, which is made of PVC resin as the main raw material, added with special additives, and extruded by an extruder. However, hygienic PVC resin powder with a low residual amount of vinyl chloride unit (VCM) is required, and a non-toxic or low-toxic (organotin or low lead content) thermal stabilization system is used to ensure the sanitation of the pipe. VCM is a carcinogen. In China, the hygienic PVC resin has a VCM residue of no more than 5 × 10-6. Lead is a cumulative toxin, especially for young children (under 6 years old), fetuses, and pregnant women. Larger.
Unlike PVC-U drainage pipes, the pressure resistance of PVC-U water supply pipes is its main mechanical index. Both the mechanical equipment factors, raw material and formula factors affect the pressure resistance of pipes, and the corresponding adjustment of the process must also be considered . Such as the gap between the extruding screw and the barrel should not be too large; a larger feed rate and a greater compression ratio; design a reasonable formula, and make corresponding reasonable process adjustments to control the degree of plasticization to 60% ~ 70% . Although the rigidity of PVC-U water supply pipe itself is large, and the low-temperature pressure resistance is excellent, the stress of the 20 ° C pressure ring can be greater than 36MPa, which is the largest amount of water supply plastic pipes for construction in the market, but its high temperature pressure resistance Very poor, so it can only be used in cold water or low temperature hot water piping systems below 45 ℃.
How to buy:
The connection method of UPVC water supply pipe is the same as that of the drainage pipe, and it is generally glued. The selection of UPVC water supply pipes should focus on the following aspects:
1. The user chooses to first apply the macro inspection of appearance and size, such as whether the circumferential wall thickness is uniform and whether the wall thickness is thick enough, more comparisons can be made.
2. The test report of the pipe and the test report of its hygienic indicators should be requested, preferably the original. Technical indicators (according to GB / T10002.1-2006) Vicat softening temperature ≥80 ℃ longitudinal shrinkage rate ≤5% dichloromethane impregnated surface without change drop weight impact test (0 ℃) TIR ≤5℅ hydraulic test 20 ℃, The ring stress is 36MPa / 38Mpa, there is no crack and leakage in 1h.