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Advantages of plastic tubes
Nov 26, 2018

Polypropylene tubes. 

(1) in the current construction and installation works, most of the heating and water supply is PPR pipe (piece). Its advantages are convenient and fast installation, economic and environmental protection, light weight, sanitary non-toxic, good heat resistance, corrosion resistance, good insulation performance, long life and other advantages. Pipe diameter nominal is called the diameter of a larger number. If PPR32 is equivalent to dn25,ppr63, it is equivalent to DN50. Pipe diameter is divided into DN20, DN25, DN32, DN40, DN50, DN63, DN75, DN90, DN110. Pipe fittings A wide range of three links, elbow, pipe hoop, variable diameter, pipe plugging, pipe card, bracket, hanger. Divided into hot and cold water pipes, cold water pipes for green strips, hot water tubes with red strips.

Valve has PPR ball valve, globe valve, butterfly valve, gate valve, there is a outer PPR material for the copper core. 

(2) Pipeline connection mode has welding, hot melt and threaded connection and so on. PPR Tube Hot-melt connection is the most reliable, easy to operate, good air tightness, high interface strength. The pipe connection uses a handheld fuse for hot-melt connection. Dust and foreign objects on pipes and accessories should be removed before connecting. When the red light of the machine is lit and stabilized, the DN〈50 hot melt depth of the pipe (piece) to be connected is 1-2mm,dn〈110 hot melt depth of 2-4mm. When connected, the pipe end is inserted into the heating sleeve without rotation to reach the predetermined depth. At the same time, without rotating the pipe fittings to the heating head heating, to reach the heating time, immediately the pipe and pipe fittings from the heating sleeve and heating head at the same time, quickly without rotation, uniform force inserted into the required depth, so that the joint to form a uniform flange. During the specified heating time, the freshly fused connector can also be corrected, but the rotation is strictly prohibited. When the pipe and pipe fittings are heated, they should prevent excessive heating and thinning the thickness. The pipe is deformed inside the pipe fittings. Rotation is strictly prohibited during hot-melt intubation and correction. There must be no open fire on the operation site, it is strictly forbidden to dry the pipe with open fire. When the heated pipe and pipe fittings are aligned vertically, the force should be light and the elbow should be prevented from bending. When the connection is complete, the pipe and fittings must be clenched to maintain sufficient cooling time, cooling to a certain extent before you can let go. When the pp-r tube is connected with the metal pipe fittings, the pp-r tube with metal inserts shall be used as the transition, the pipe fittings and the pp-r pipe are connected by hot-melt interpolation, and when connected with metal fittings or sanitary ware hardware fittings, a threaded connection should be used, and the polypropylene raw material belt should be used as the sealing filler. If the faucet is picked up on the mop pool, the inner tooth elbow (thread inside) is installed at the end of the PPR tube. Pipeline installation process, must not push too hard, so as not to damage the wire buckle accessories, resulting in leakage at the junction. Pipe cutting can also be used special tube shear cut off: Pipe shear blade Card should be adjusted to match the cut pipe diameter, rotation cut should be evenly added, cut off, the fracture application supporting the whole circle.

When the pipe is broken, the section should be perpendicular to the pipe axis and without burrs. 

(3) In the pipeline installation process, can be layered or a single set of water pressure test. The working pressure and test pressure of all pipelines are: 0.4MPA working pressure, test pressure is 0.6Mpa, high zone and central working pressure are calculated in 0.6Mpa, test pressure is 0.9Mpa. After the piping system is installed, check thoroughly, check the installed pipes, valves, gaskets, fasteners, etc. , all in line with the design and technical specifications, the unsuitable and piping together to test the parts removed, replaced with temporary short tubes, all openings to be closed, and from the lowest irrigation, high air discharge. The test pressure qualified pipe for blowing and washing work, until the dirt flushing, and do a good job of sweeping cleaning records and test pressure records and so on. The test pressure is 1.5 times times the operating pressure of the system, but must not be greater than the allowable pressure of the pipe. The test should be slow water injection, after filling should do seal inspection.

Pressurized should be used hand pressure pump slow boost to test pressure, voltage stabilizer 1h, pressure drop less than 0.05Mpa, and then down to the working pressure of 1.15 times times the voltage regulator 2 hours, the appearance of inspection, non-seepage pressure drop no more than 0.03MPA for qualified. 

(4) The installation should also pay attention to the handling and installation of pipes should avoid touching sharp objects, in order to prevent pipe breakage. Pipeline installation process, should prevent paint and other organic pollutants with pipe, pipe fittings contact. installation interruption or completion of the open place, must be temporarily closed good, so as not to enter the debris. The water supply piping system should be rinsed by aqueous before acceptance. Flushing water flow rate should be greater than 2m/s, rinse, should not leave a dead angle, each water distribution point faucet should be opened, the lowest point of the system should be set up water outlet, cleaning time control at the flushing outlet drainage of the quality and water intake is equivalent. After rinsing, the drinking water system also uses 20-30mg/l free chlorine water to fill the pipeline for disinfection. Chlorine containing water should be stranded more than 24h in the tube. After disinfection of the pipeline, rinse with drinking water, and by the Health Management department sampling test, water quality in line with the current national standard "Drinking Water hygiene standards", can be delivered for use. Within 30 minutes, two boost is allowed to rise to the prescribed test pressure. Be sure to pay attention to the conversion of pipe diameters when budgeting and picking up materials. such as the drawing table this paragraph for the DN20 to mention the PPR25 pipe (pieces). Be sure to use the same manufacturer's products, because different manufacturers of products contain different proportions of ingredients. It can cause adhesion or more adhesion.

Hard PVC Tubes 

(1) The drainage is uPVC pipe (piece). It is widely used in pipeline installation because of its advantages of light weight, corrosion resistance and high strength. Under normal circumstances, the service life can generally be up to 30-50 years. The inner wall of uPVC pipe is smooth and the friction resistance of fluid is small, which overcomes the defect that the cast iron pipe affects the flow rate due to rust and scaling. Pipe diameter is also larger than the nominal diameter of a number.

such as DN100 is u-pvc110.dn150 is u-pvc160. Pipe fittings are divided into oblique three-way, four-way, elbow, pipe hoop, variable diameter, pipe plugging, water storage bend, pipe card, hanger. 

(2) The connection with the drainage glue bonding. Adhesives must be rolled evenly before use. Pipe and socket parts must be cleaned up, the smaller the gap, the more easy to use sand cloth or saw blade to beat the joint surface, the mouth of the thin floor evenly brush glue, socket parts brush two times glue, after the glue dry 40~60s inserted into place, at the same time should pay attention to the appropriate increase or decrease in the glue dry time according to climate change. Adhesion is strictly forbidden to water, pipe in place must be flat in the ditch, to the joint dry after 24h began to backfill, backfill with sand to fill the pipe around, leaving the joint area and then a large number of backfill. To use the same manufacturer's products. When the uPVC tube is connected with the steel pipe, the steel pipe connection must be wiped with glue, and the uPVC tube should be heated and softened (but not charred) and then plugged into the steel pipe and cooled for treatment, such as adding tubing hoop will be better. For large area damage of pipe need to replace the whole section of pipe, can be used double-bearing connector replacement pipe method. Solvent method can be used to treat leakage at solvent bonding. At this time, the water in the pipe is drained, and the negative pressure is formed in the tube, and then the adhesive is injected into the pores of the leakage site. Because of the negative pressure in the tube, the adhesive will inhale the pores to achieve the purpose of stop leakage. The sleeve bonding method is mainly aimed at the leakage of the pipe through the hole and the joint. At this time, the use of long 15~20cm of the same caliber pipe, its longitudinal cut, according to the method of bonding joints will be the casing inner surface and the external surface of the pipe to beat hair, glue after the cover in the leak tight. Glass fiber method is the use of epoxy resin reinforcement agent into a resin solution, with fiberglass cloth impregnated resin solution, evenly wound in the pipe or joint leakage of the surface, after curing into FRP.

Because of the simple construction of the method, easy to master the technology, good plugging effect and low cost, it has a high value of popularizing and using in the seepage prevention and leakage. 

(3) The water pressure test of the piping or pipe network system must be glued to dry 24h before it can be carried out. The hydraulic test of the pipeline must comply with the test pressure rules of the non-metallic pipes stipulated by the State. For pipe test length ≯1.5km without node connection, the test length of pipe segment with nodes is ≯1km. pipe or pipe network test pressure must not exceed 1.5 times times the design work pressure, the lowest ≮0.5mpa, and maintain the test pressure 2h or meet the special requirements of the design, no leakage phenomenon is qualified. Budget, also pay attention to the conversion of pipe diameter when loading. must also use the same manufacturer's products, to prevent different manufacturers of products contain different proportions of ingredients. can cause adhesion or no adhesion at all.