Characteristics of HDPE
All HDPE products have similar properties regardless of their purpose. These characteristics are as follows:
- Long service life - manufacturers guarantee 50 years of use.
- High resistance to corrosive environments - polyethylene products can not be corroded and biologically inert.
- Elastic qualities - the plasticity of the material allows avoiding the rupture of communications during freezing of water and considerable deformation in the case of soil shear.
As we can see, the distinctive qualities of HDPE are its advantages. And if to add to these properties simplicity of installation, a small weight and a democratic price, it becomes clear why the products made from HDPE became popular.
In comparison with the above pluses, the shortcomings of the HDPE seem insignificant. Thus, ultraviolet rays can reduce the service life of communications, and an increase in the temperature of the liquid to be run can lead to deformation and even melting of the material. Oxygen permeability is also considered a disadvantage.
Methods for the manufacture of HDPE
Polyethylene pipes are produced using one of three technologies.
- Pneumatic formation - the polymer is fed into a mold where the product is formed under the influence of a pneumatic pressure supercharger.
- Extrusion - polymer is melted, after which the mass is extruded from the extruder, stretched and solidified in the form of the finished product.
- Die casting - the polymer mass is injected into the mold and evenly distributed over its walls under high pressure.
Where the HDPE pipes are used
The purpose of polyethylene pipes is determined by three main parameters: the strength index, the outer diameter and the polyethylene brand.
In general, HDPE products are used in pressure and non-pressure pipelines and cable communications.
Smooth pressure pipe is used for water and heat supply. It has high internal strength and low ability to gas diffusion, ensures unimpeded movement of the transported liquid.
The sizes of produced communications vary from 16 to 110 mm, and the length reaches 12 and more meters. Such products can have as one, and two layers.
HDPE pipes for non-pressure systems have good heat resistance and rigidity, because the drainage system and sewerage operate under increased pressure from the outside.
The diameter of pipes of non-pressure household systems is 110 mm, industrial - more than 300 mm. Most often in sewer systems use two-layer pipes of HDPE-PVD type.
The cable box must have smooth inner walls and increased stiffness. This product must protect the internal electrical wiring from mechanical damage and moisture.
The wiring box can be either single-layer or double-layered. Single-walled pipe is used in places where it is relatively easy to lay out communications. In areas with increased load, double-walled HDPE-PVD pipes are used.
Assembling the communication PND
Regardless of the difference in purpose, any pipe can be installed in the pipeline system in the following basic ways:
- The threaded method - mounting on fittings and couplings, is carried out with a simple set of spanner keys. In this way, the channels for the cable are connected.
- Welding method - welding of the joint between pipes, it requires an expensive tool.
- Crimping method - mounting on the collet or press fittings, is carried out using a set of press keys. This is how small diameter pipes are connected.
Having become acquainted with information about what HDPE products are, what they are needed for and what their differences are, it's easy to choose materials that fit the parameters for you.
