Pipe
Polypropylene (PP) is a thermoplastic (hot meltable) made from the polymerization of propylene, which is the least dense plastic, usually translucent and colorless solid, odorless and non-toxic.
Because of its low-temperature brittleness, polypropylene is usually copolymerized with a small number of ethylene molecules in order to improve this shortcoming, thus dividing it into homopolymer and copolymer polypropylene.
Polypropylene has excellent pressure-bearing properties, and is very easy to hot-fusion welding after the pipe is made, it can withstand higher temperatures, so it is widely used in home furnishing water piping.
Once the PPR pipe is hot-fused according to the specification, it can never leak, which means that the connection itself is theoretically free of defects and is a permanent connection.
Commonly used PP-R pipe specifications are 5, 4, 3.2, 2.5, 2 five series
PPR pipe specifications PPR pipe is divided into five series of 11, 9, 7.4, 6, 5 according to the standard dimensional rate SDR value.
PPR pipe specification PPR standard dimensional rate SDR: is the ratio of nominal outside diameter dn and nominal wall thickness en of PPR pipe.
PPR pipe specifications SDR and PPR pipe series are related as follows: SDR = 2S + 1
PPR pipe fittings specifications are expressed in the following way.
PPR pipe fittings nominal outside diameter dn refers to the nominal outside diameter of the PPR pipe connected to the PPR pipe fittings. the wall thickness of the PPR pipe fittings should be no less than the wall thickness of the PPR pipe of the same PPR pipe series S. the wall thickness of the PPR pipe should be no less than the wall thickness of the PPR pipe of the same PPR pipe series S.
Most companies PPR pipe fittings are only the highest standard S2 a series, hot and cold water are all applicable
PPR pipe specification S5 series --------------1.25 MPa (12.5 kg)
PPR pipe specification S4 series --------------1.6MPa(16kg)
PPR pipe specification S3.2 series ------------2.0 MPa(20kg)
PPR pipe specification S2.5 series --------------2.5 MPa(25kg)
PPR as a new plumbing material, PPR pipe has the unique advantage that it can be used as both cold water pipe and hot water pipe, due to its non-toxic, light weight, pressure resistance, corrosion resistance, is becoming a promotional material, PPR pipe is not only suitable for cold water pipes, but also for hot water pipes, and even pure drinking water pipes.
The interface of PPR pipe adopts hot fusion technology, and the pipes are completely The interface of PPR pipe is fused together, so once the installation pressure test is passed, there will not be the same as aluminum plastic pipe aging leak phenomenon over time, and PPR pipe will not scale, PPR pipe is claimed to never scale, never rust, never leak, green advanced water supply materials.
There are many choices of water pipes, such as PPR water pipes, copper pipes, copper-plastic pipes (aluminum-plastic pipes), pvc pipes, iron pipes, etc. PPR water pipes are very ideal. The reason is that good PPR water pipe is reliable in quality, completely comparable to copper pipe; there is also a more acceptable price, much lower than copper pipe; in addition there is no rust and copper rust.
PPR water pipe has cold water pipe and hot water pipe, is the difference between the thickness of the wall, it is recommended to use hot water pipe to row, the wall is thicker, better quality, and the price is not much more expensive. In addition, once you find that the water pipe was extended for no reason, must be corrected by the workers. Because not only calculate more money for water pipes, but will affect the use of the effect, especially the use of hot water effect.
The water pipe is recommended to go along the top of the wall, with the ceiling, etc. to trim, never under the floor. The pressure test of the water pipe after arranging the water pipe is also very important. Test, everyone must be present, and the test time of at least 30 minutes, conditions permit, the best one hour. 10 kg pressurization.
Another point is that the water pipes all need to be fixed. In fact, the important reason for fixing is because of minimizing the sound of water flow. Use as few joints as possible for water and gas pipes. Straight pipes must be used as a complete one. Where joints must be made, such as at bends, thick white paint must be used, not raw material tape. After the gas pipe is installed and accepted, you can ask the workers to apply a layer of thick white paint on the outside of all the joints to be sure!
The size of domestic PPR hot water pipe is generally 25mm x 4.2mm, 20mm x 3.5mm, these two specifications.
PPR is divided into hot water and cold water, there are red lines on the pipe is used for hot water, blue lines are used for cold water, red lines of hot and cold water can be used.
The essential difference between PPR cold water pipe and hot water pipe is that the wall thickness is not the same. This wall thickness is different means that the wall thickness of hot water pipe is thicker when the outer diameter of cold water pipe and hot water pipe is the same, while the wall thickness of cold water pipe is thinner.
The easiest and fastest way to distinguish is to see if there is a red and blue marker line on the body of the pipe, there is a red marker line is generally hot water pipe, blue marker line is generally cold water pipe, which is the way used by most domestic industrial plumbing.
But not all PPR pipe manufacturers will be marked red and blue lines on the water pipe, because this method itself is not very strict. Then it is mainly through the spray code of the pipe body to identify the hot and cold water pipes. Mainly through the standard size of the water pipe than SDR and pipe series S to identify whether the water pipe can be used for hot water. The standard size ratio commonly used for hot water is SDR6 / SDR7.4, and the corresponding pipe series is S2.5 / S3.2.
Thermal expansion coefficient of PPR water pipe: PPR pipe line expansion coefficient is large, about 0.15mm/m-℃, meaning that by the external temperature (such as winter and summer) or internal water temperature (cold and hot water) changes, there is a large amount of deformation, because the PPR pipe is a rigid straight pipe, itself can not digest the amount of deformation, it is easy to cause the pipeline system bending deformation or even leakage 1.5 resistance to high and low temperatures: PPR pipe poor resistance to low temperatures. PPR has cold brittleness (brittle point of -20 ℃), in winter (5 ℃ below) construction that requires special care, PPR long-term use temperature of 70 ℃ (50 years, 1MPa), the maximum use temperature of 95 ℃.
PPR water pipe is a long-term use of decoration materials, if you have to divide a good or bad, the most important thing is to compare the kind of water pipe is more durable, other performance are marketing needs. To compare the good and bad of PPR water pipes, mainly from the following aspects.
The first choice depends on the selection of PPR water pipe materials
The physical and chemical properties of the selected raw materials are directly related to the quality of water pipes, whether the selected materials are healthy and environmentally friendly, there will never be other additions, which is the most basic.
Secondly, the raw materials are related to the most essential PPR water pipe welding performance
Raw material is not good PPR water pipe, hot fusion will appear thin and soft phenomenon is not conducive to welding operations, and raw materials good PPR water pipe hot fusion welding mouth will be uniform expansion easy welding operations.
Next, look at the copper fittings
Although the amount of copper fittings is relatively small, but the copper parts of the good or bad can explain the overall level of PPR water pipe process. Brass parts without nickel-plated brass (yellow) is better than nickel-plated brass (silver-white), the quality of brass is very important, if the use of poor quality brass, the mechanical properties will certainly be affected; quality brass wire mouth pieces will be heavier than nickel-plated brass wire mouth pieces
Finally, the more intuitive is the amount of material used
Because whether the material is sufficient related to the manufacturing cost, of course, also related to the quality of the product, from the water pipe wall thickness, the amount of copper parts is sufficient, is the real table as one.
Better thermal and sound insulation, low flammability. Corrosion-resistant, no chemical effect on all ions in the water and chemicals in the building. Environmental protection is different, PPR pipe colorless and tasteless, health and healthy, recyclable. Strong pipe connection, hot fusion connection to eliminate the hidden danger of water leakage.
PPR as a new plumbing material, PPR pipe has the unique advantage that it can be used as both cold water pipe and hot water pipe, due to its non-toxic, light weight, pressure resistance, corrosion resistance, is becoming a promotional material, PPR pipe is not only suitable for cold water pipes, but also for hot water pipes, and even pure drinking water pipes. Once the installation pressure test is passed, there will not be the same as aluminum plastic pipe aging leak phenomenon over time, and PPR pipe will not scale, PPR pipe is said to never scale, never rust, never leak, green advanced water supply materials.
PPR pipe diameter: PPR pipe diameter can be from 16mm to 160mm, mainly used in home decoration is 20mm, 25mm two kinds (respectively, commonly known as 4 points of pipe, 6 points of pipe), of which 4 points of pipe used more.
The wall thickness is 2.8mm and 3.4mm. The 4-part pipe is 15mm, and the 6-part pipe is 20mm.
In all the fittings, the inner and outer wire joints are more expensive, and a wire joint is even more expensive than the price of a meter of water pipe, while the other fittings are relatively cheaper.
When buying, first look at the appearance of high-quality pipes, smooth appearance, complete identification, accessories also have the brand name; poor quality products can not do these.
Because the quality of the pipe using 100% imported PPR raw materials, poor quality pipe only part of the PPR raw materials, the two have a big difference in performance, reflected in the following aspects.
Toughness: good quality PPR pipe toughness, can be easily bent into a circle without fracture.
Thermal expansion and contraction: good water pipes can still maintain hardness at high water temperatures, while poor quality pipes are softened at 60 degrees water temperature.
Service life: quality products are guaranteed for 50 years, while poor quality products can only be 5-6 years.
PPR pipe: as a new type of plumbing material, PPR pipe has the unique advantage that it can be used as both cold water pipe and hot water pipe, due to its non-toxic, light weight, pressure resistance, corrosion resistance, is becoming a promotional material, PPR pipe is not only suitable for cold water pipes, but also for hot water pipes, and even pure drinking water pipes. Completely fused together, so once the installation pressure test passed, there will be no aging leak phenomenon like aluminum plastic pipe over time, PPR pipe is said to never scale, never rust, never leak, green advanced water supply materials.
PPR water pipes are generally bonded by hot fusion, specifically in the connection needs to pay attention to the following points:
1. Heating temperature and time
2. Welding depth
3. Whether the die is worn
4. PPR material is good or bad
5. whether the water pipe port is cracked
Finally, the water pipe needs to be pressure tested after installation.
