PP pipe installation and selection criteria

PP pipe standard:

• Execute HG 20539-92.

·Select the production of glass fiber modified polypropylene material treated with coupling agent, the transportation of general purpose water and corrosive liquid.

·The sanitary performance of drinking water pipes complies with the provisions of GB/T17219.

Excellent quality of glass fiber reinforced polypropylene FRPP pipe:

Illustration: PP tube

·Long service life----The FRPP pipe can be safely used for more than 50 years under the rated temperature and pressure conditions.

·Excellent corrosion resistance----Resistant to the corrosion of most chemicals, can withstand a wide range of acid and alkali corrosion with a pH range of 1-14.

·Excellent anti-wear performance-----When conveying ore slurry, the wear resistance of FRPP pipe is more than 4 times that of steel pipe.

·Higher stiffness----The FRPP pipe is not easily deformed due to the addition of glass fiber reinforced materials.

·Heat-resistant insulation and energy-saving-----FRPP pipe has a maximum operating temperature of about 95 degrees. The thermal conductivity of this product is only 1/200 of that of steel pipe, so it has better insulation performance.

·Reliable connection performance-----The strength of the FRPP tube hot melt interface is higher than that of the pipe body, and the joint will not be broken due to soil movement or load.

·Good construction performance-----The pipeline is light in weight, the welding process is simple, the construction is convenient, and the comprehensive construction cost is low.

PP pipe performance:

PP pipe size:

The size and size of PP pipe is not a simple geometric size, but it is a functional size that provides mechanical properties and fits with pipe fittings. The standard has high requirements for dimensional deviation, and improper control or non-strictness in machining is extremely prone to excessive standards. In addition to relying on raw materials and processing quality assurance, the mechanical properties of plastic pipes are mainly provided by wall thickness, the wall thickness does not meet the standard requirements, and pipe rupture occurs.

Pipe specifications of PP pipe:

The opacity of PP pipe:

The opacity is to ensure the hygienic performance of the water conveyance in the pipe (to avoid the harmful substances such as algae) and the anti-aging properties of the material, especially for the pipe used for the surface, so the light transmittance is too high, which will reduce its hygienic performance.

Mechanical properties of PP pipe:

The standard requirements for impact specimens are <10%, and such products that do not meet this standard may be broken during normal transportation, handling, installation and use (especially in winter) in the event of an external impact.

Hydrostatic test of PP pipe This is the most important technical requirement in pressure pipe. Polypropylene, especially PP-R pipe, is a thick-walled product in plastic pipe. It is easy to cause various plastic products due to improper processing due to improper processing. Quality issues, even with regular pipe materials. Therefore, for different raw materials, especially raw materials with a narrow processing range (according to individual domestic materials and Korean materials), it is necessary to study and find out the corresponding optimum processing conditions, and also to use processing with stronger plasticizing ability. Equipment to ensure the mechanical properties of the final product.

PP pipe marking:

The main technical information of PP-R pipe should be reflected in the logo. It is an important basis for enterprise production, user use, quality traceability and dispute arbitration. This is clearly defined in the national standards.

Identification of PP pipe:

1. Take a little PP-R material and ignite it. After burning, it will be dripped on white paper. The ash residue with poor quality is good. The quality is like wax, and the color is translucent.

2. The burnt small melted part is clamped with iron tongs, and the wire is pulled out. The molecular chain of polypropylene is very long, and it has good ductility and flexibility. The length of the wire is pure high quality raw material. If the pipe is easily broken, it means that there are more mixed materials.

3, high-quality PP pipe PP-R products burned very light taste, mixed with miscellaneous materials will have an unpleasant smell; after burning, if the section is dark red, it is proved to be mixed with calcium carbonate powder.

After purchasing a good PPR tube, we can't ignore the quality of the installation. The simple way to judge is whether the overflow around the melt interface is uniform, the overflow side is annular, and the tube and tube are well bonded. The marking lines on all pipes are still in line after installation, and some of the pipes have protruding lines on the outside and should be aligned with them. After the installation is completed, first pass the water check. After confirming that there is no water leakage, pressurize it to 4Mpa with the test press for 24 hours. There is no obvious pressure drop and water leakage, indicating that the installation is qualified and the air tightness is good. In addition, it is recommended that you use a buried tube in the installation.

A. Touch: Whether the texture is fine and the particles are uniform. Nowadays, PP pipes mainly have white, gray and green colors. Under normal circumstances, recycled plastics can't be white, so many people think that white is the best. In fact, this view is one-sided. As technology updates increase, color is not the standard for distinguishing PPR tubes. If the tube is good or bad, it can't solve the problem. Touching it, the coarse particles are likely to be mixed with other impurities.

B, smell: there is no smell. The main material of the PPR pipe is polypropylene. The good pipe has no odor, and the poor one has a strange smell. It is likely to be blended with polyethylene instead of polypropylene.

C, pinch: PPR tube has a considerable hardness, can be squeezed into a deformed tube, certainly not a PPR tube.

D, ç ¸: Good PPR tube, "rebound" is good, too easy to smash naturally is not a good PPR tube. However, the hardness is not equal to the elasticity. If you have a PPR tube that cannot be broken, you should leave doubts. Because some unscrupulous manufacturers increase the hardness of the pipe by adding too much impurities such as calcium carbonate, such a pipe is prone to brittle cracking for a long time.

E, burning: Ignition and burning, very intuitive and very useful. The PPR pipe mixed with recycled plastic and other impurities in the PP pipe material will emit black smoke and have a pungent smell; after burning, the pipe material will not emit black smoke or odor, and the melted liquid will still be clean after burning. .

PP pipe installation notes:

1. In order to ensure the installation quality of PP-R polypropylene pipe, the inner and outer walls of the pipe should be smooth, flat, free of bubbles, cracks, cracks, dents, peeling and severe cold spots and obvious marks.

2. The pipe of PP pipe is cut by small copper pipe cutter. The blade is perpendicular to the outer wall of the pipe. When the knife is tight, it should not be too tight. After the cutting line is first wound around one turn, the depth of the knife is rotated every turn, and the pipe is cut quickly. Slowly turn to prevent the broken pipe from falling. At the cutting point, apply a reaming cone cutter to the neck portion of the nozzle, or use a round file to eliminate the chamfer inside the tube.

It can also be cut with a special pipe: the pipe clamp should be adjusted to match the diameter of the pipe, and the force should be evenly applied when the screw is cut. After cutting, the complete round of the complete rounder should be applied at the fracture.

3, PP-R polypropylene pipe installation side connection can be welded, hot melt and threaded connection, etc., and the hot melt connection is the most reliable. The PP pipe is easy to operate, has good air tightness and high interface strength.

Before connecting, firstly machine the pipe end to a groove of about 30 degrees, and wipe the connected pipe and pipe end with cotton yarn to make it dust-free, oil-free, and insert the mark.

4. When the PP-R polypropylene pipe is connected with the metal pipe fitting, the PP-R pipe with metal thread insert is used as the transition. The pipe fitting is connected with the polypropylene pipe by hot-melt socket, and the hardware of the metal pipe fitting or sanitary ware. When the fittings are connected, the spiral connection is used, and the polyvinyl fluoride raw material tape is used as the sealing filler, and the thick white paint and the hemp yarn are not suitable.

5. The pipe support should be buried before the pipeline is installed. The maximum installation distance of the cold and hot water pipe supports meets the requirements of the specification.

6. The horizontal pipe of the PP pipe is bent longitudinally and horizontally, the verticality of the riser pipe, and the installation deviation of the pipes and valves in the row must meet the requirements.

PP pipes belong to public pipes, so during construction, the following problems should be noted when installing PP-R pipes:

1. PP pipe is less rigid and less rigid than metal pipe, and should be protected during handling and construction to avoid mechanical damage caused by improper external force. After the dark application, the position of the pipeline should be marked to avoid damage to the pipeline due to the secondary decoration.

PP pipe has a certain low temperature brittleness below 5 °C. Be careful when constructing in winter. Cut the pipe slowly with a sharp tool. The installed pipelines should not be stressed or tapped, and if necessary, cover the parts that are vulnerable to external forces. 3, PP-R tube is prone to aging degradation by ultraviolet radiation for a long time, and it must be wrapped in a dark protective layer when installed outdoors or in direct sunlight.

In addition to the mechanical connection of the PP pipe to the metal pipe or water machine, such as threaded inserts or flanges, the other parts should be hot-melt joints to make the pipe integrated without leakage.

The coefficient of linear expansion of the PP pipe is large (0.15mm/m °C), and technical measures must be taken to prevent the pipe from expanding and deforming when the pipe is installed or not directly buried.

After the pipeline is installed, it must be tested before sealing (direct burial) and covering the decorative layer (not directly buried). The pressure test pressure of the cold water pipe is 1.5 times of the working pressure of the system, but not less than 1 MPa; the test pressure of the hot water pipe is twice the working pressure, but not less than 1.5 MPa. Pressure test time and method technical regulations.

When PP pipe is used or not directly buried in the dark pipe, the branch and hanger must be installed as required.

PP tube purchase:

The three-type polypropylene pipe (PP pipe) adopts hot-melt welding technology in the hot and cold water transportation project, and its comprehensive technical performance and economic index are superior to galvanized pipe, UPVC pipe, aluminum-plastic composite pipe, cross-linked polyethylene pipe and poly Butene tube is the leading product of water supply pipeline in developed countries in Europe and America.

The three-type polypropylene pipe (PP pipe) for cold and hot water has the advantages of hygienic non-toxicity, heat resistance, corrosion resistance, good heat preservation and simple installation, and can be directly used for pure water and drinking water pipe systems.

The plastic coated copper tube has the advantages of high temperature resistance, corrosion resistance, high strength and good permeability resistance.

Compared with the traditional cast iron drain pipe, the rigid polyvinyl chloride (PVC-U) pipe for building drainage has the advantages of light weight, low fluid resistance on the inner wall and good corrosion resistance.

Regardless of the type of pipe, consumers should pay attention when purchasing PP pipes:

1. Whether the stated implementation standards on the pipe are the corresponding national standards, and try to purchase products that implement national standards.

2, the appearance of the pipe should be smooth, flat, no blistering, uniform color, no impurities, uniform wall thickness.

3, the same material, choose a thicker pipe.

Pay attention when using pipes:

1. Conceal the buried water pipe as far as possible to use a complete pipe, use less joints, and try not to go underground.

2. After the installation of the water pipe is completed, it must be tested first to be closed.

3. After the installation is completed, you must obtain the warranty book and the pipeline trend map.

It is recommended that water pipes or professional teams install water pipes.

PP pipe has been valued by all countries in the world for its excellent hygienic performance and heat, pressure, corrosion resistance, softness and shock resistance. It is a truly environmentally friendly water pipe in building hot and cold water pipes.