Polyethylene is used to produce and cover various types of pipes in various applications such as drinking water, sewage, gas, heating and plumbing pipes for homes, solid material transfer pipes, drip irrigation, protective pipes (wire and cable and glass fiber passage, etc.).<\/p>\n
Polyethylene pipes have been in use for about 40 years, and gradually, with the recognition of the advantages and functions of this pipe and the gradual improvement of the characteristics used in many applications, they replaced various types of concrete, steel, cast iron and PVC pipes.<\/p>\n
The flexibility of polyethylene pipes has made the movement and installation of pipelines much easier and less expensive than steel pipelines. The flexibility of these pipes allows for the bypassing of obstacles and the reduction of joints and connections. These pipes are much more resistant to natural disasters such as earthquakes than other types of pipes.<\/p>\n
Drinking water networks
\nUrban water supply networks
\nUrban and rural sewage networks
\nPressure irrigation
\nUrban and rural sewage
\nCable coating, metal pipe
\nIndustrial water supply<\/p>\n
High resistance to breakage and cracking
\nVery high chemical resistance
\nResistance to corrosion
\nHigh flexibility
\nFunction at temperatures from minus 40o c to 70o c
\nAbility to use on uneven terrain
\nLong life
\nEasy and fast execution
\nHigh hydraulic resistance
\nSound insulation
\nExcellent earthquake resistance
\nImpact resistance
\nResistance to abrasion and scratching:
\nPolyethylene pipes are very suitable for transporting liquids that are abrasive or scratch-resistant due to the following polymer properties:<\/p>\n
Low modulus of elasticity
\nHigh impact resistance
\nFriction coefficient Low
\nHigh chemical inertia The lifespan of polyethylene pipes against liquids containing abrasive particles and scratches is up to 10 times higher than that of metal and clay pipes.
\nThe resistance of polyethylene pipes to natural disasters such as earthquakes is much higher than that of other types of pipes. The figure below shows the damage rate in the 1995 Japanese earthquake for different types of pipes.<\/p>\n
PE63<\/p>\n
PE80<\/p>\n
PE100<\/p>\n
In the production of polyethylene pipes, the higher the pressure classification (PE63 to PE100), in addition to saving on material consumption, it increases the cross-sectional area of \u200b\u200bthe pipe at a constant outer diameter, which increases the pipe’s transfer capacity. If we assume that the transfer capacity is constant, the transfer speed can be reduced and, as a result, smaller pumps can be used for transfer. This reduces costs. In addition, when repairing pipes and using Amster pipes in the previous pipe – the loss of transmission capacity will not be large.<\/p>\n
PE100 has advantages in non-pressure pipes, apart from pressure pipes, as it has a higher internal strength than standard heavy polyethylene (1250MPA versus 950MP), a higher modulus, greater radial stiffness, which is a great advantage in pressure and non-pressure sewage networks.<\/p>\n
Long-term strength or the basis of the hydrostatic design of the pipe determines the life of a pipe at a given pressure and temperature and is usually carried out by a series of tests at different pressures and temperatures over a specified period of time. To check the 50-year life of the pipe, the pipe must be obtained without creep tension.<\/p>\n
Rapid crack growth is a very important defect that is frequently seen in transmission lines. The largest crack reported for a steel pipe was 11 km long, and for polyethylene, the largest crack was observed in a gas pipeline in Hungary with a diameter of 315 mm and a length of 700 m. Resistance to rapid crack growth is a term used to examine impact strength. These tests are used at a specific temperature to determine the pressure above which rapid crack growth occurs. This pressure is called the critical pressure.
\nThe probability of rapid crack growth in pipes increases with increasing diameter and thickness of the pipe at low temperature and high ambient pressure. The term crack growth is used when the crack length is 4.7 times greater than the nominal outside diameter of the pipe.<\/p>\n
\nThe slow crack growth characteristic shows the long-term and environmental resistance of the pipe. The initiation of crack growth depends on the internal stress residual from the processing time in the pipe and the installation pressure of the pipe. The crack test examines the long-term creep properties of the material, these tests are known as ESCR.
\nIf a crack grows and a crack forms in the pipe, it is said that the pipe is bent. Pipes made of first-generation polyethylene bend in 100 hours, but the next generation bends in 1000 hours and the current generation lasts nearly 100 years.<\/p>\n
This is important for the transmission of natural gas. Because it is possible for it to penetrate through polyethylene. Of course, the measured leakage rate is so low that it does not affect the transmission of gas.<\/p>\n
Gas leakage rate from polyethylene<\/p>\n
The expansion coefficient is necessary for calculations related to the specific diameter and the amount of pressure on the pipe joints and the surrounding soil.<\/p>\n
The amount of heat that a plastic pipe can transfer through its wall depends on the thermal conductivity of the pipe. The thermal conductivity of polyethylene is 0.43\u00a0\u00a0\u00a0\u00a0 w\/mok. ASTM C177<\/p>\n
For the transport of beverages, the hygiene of the materials in the pipe is important. The hygiene standards related to polyethylene are:
\n1- FDA, CFR, Title 21 (1994) 177. 1520. Olefin polymers\u00a0\u00a0\u00a0\u00a0 (USA)
\n2- NS<\/p>\n","protected":false},"excerpt":{"rendered":"
Polyethylene is used to produce and cover various types of pipes in various applications such as drinking water, sewage, gas, heating and plumbing pipes for homes, solid material transfer pipes, drip irrigation, protective pipes (wire and cable and glass fiber passage, etc.). Polyethylene pipes have been in use for about 40 years, and gradually, with […]<\/p>\n","protected":false},"author":1,"featured_media":430,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[26],"class_list":["post-425","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-7","tag--pipe-ethylene"],"_links":{"self":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts\/425","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/comments?post=425"}],"version-history":[{"count":6,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts\/425\/revisions"}],"predecessor-version":[{"id":881,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts\/425\/revisions\/881"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/media\/430"}],"wp:attachment":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/media?parent=425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/categories?post=425"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/tags?post=425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}