All about small diameter rigid plastic tubes: Instruction + Video

All about small diameter rigid plastic tubes: Instruction + Video Rigid plastic pipes of small diameter Plastic pipes are usually used to drain sewage and supply water to an apartment.

But in order to choose the right pipes, you should familiarize yourself with all the features of products of different diameters. If you have precisely determined for which sphere to use this or that pipe, you can easily choose materials for your home.

Characteristics of Plastic Pipes

A thermoplastic polymer is used to manufacture small diameter rigid plastic tubes. The creation of such pipes is carried out according to a certain standard, and for this reason all products have the same characteristics:

  • According to GOST, the material's melting temperature is +149 degrees.

  • For plastic, the tensile strength should be 35 N / mm 2.
  • For plastic, the coefficient of linear expansion should be 0.15mm / m о С.

These products may have different diameters. For example, plastic tubing with a diameter of 3 mm can be used to make laboratory equipment.

For plumbing or sewerage systems, pipes with a diameter of 5 cm are often used.


This is one of the most important characteristics. When choosing tubes, it should be borne in mind that they have an inner and outer diametrical section. Note also that Russian manufacturers take the outer diameter as the main parameter. If you need to create a sewage or water supply system for internal purposes, as a rule, products with a small diameter are used.

In this case, the minimum value is 1. 6 cm, and the maximum is 5 cm. In the case when it comes to creating a pipeline for conducting drinking water, it is permissible to use products with a large diameter.

Varieties by field of application

There are 3 main types of polypropylene pipes, but there are enough of them to replace the no longer quoted metal products. The PN10 model has very thin walls, but they have been used to create a water supply system for more than 50 years.

They can be used for cold and hot water supply. In addition, they can be used when arranging a warm floor.

Polyvinyl chloride pipes can also be used to create storm sewers, and then the external indicator of the volume of pipes will be from 2 to 11 cm, and the internal indicator, respectively, from 1.6 to 9 cm.

Models of rigid plastic pipes of small diameter, marked PN20, are designed for long-term use, from 25 years and above.

In such products, the wall thickness is 1. 8 cm. Note that the outer diameter may be the same as that of the previous type of pipes, but inside it will still be smaller. Due to this, they can be used in the case when the internal pressure is from 2 MPa. They can also be used when installing heating systems.

This becomes available due to its resistance to high temperatures.

Such pipes can retain their excellent properties even at +90 o . Note also that products with the PN10 marking can be used at a temperature that is 2 times less. When creating pipes with the PN25 marking, additional fiberglass reinforcement is used. In this case, the period of use largely depends on the operating pressure, and also on the temperature of the liquid.

The characteristics are as follows:

  • Can withstand high pressure, but not more than 2.5 MPa.
  • For products, the outer diameter ranges from 2.1 to 8 cm.
  • The indicator of the inner section varies from 1.

    3 to 5 cm.

  • In the thinnest pipes, the wall thickness is 0.4 cm, and the largest ones have 1. 3 cm.

It is these characteristics that determine the final cost of pipes.

When choosing products for water supply, diameter plays a huge role, since this directly affects the throughput.

Polyvinyl chloride and its description

Polyvinyl chloride pipes are inexpensive when compared with similar products, but made of iron. Very often they use transparent pipes. They can be used to create ventilation lines and laboratory equipment. Note that such products cannot be used if the temperature is above +100 degrees.

This is due to the fact that in this case, the material will begin to emit hydrogen chloride, and this is very harmful to health.

Note that polyvinyl chloride is smooth and excellent in repelling dirt. You can install such transparent tubes almost anywhere, as they are very flexible.

Advantages and disadvantages

The advantages of small diameter plastic tubes include:

  1. All about small diameter rigid plastic tubes: Instruction + Video Long service life, as such products can be used for more than 50 years.
  2. Small size and light weight.

    This allows the pipes to be easily transported and loaded for transportation.

  3. Convenience of installation. Laying transparent PVC pipes can be done even by someone who has not previously been involved in similar work and has no experience.
  4. Low noise level. With a complete system, you will hear very little noise.

  5. Security. Such products are not dangerous for humans and their health, since they do not emit harmful vapors and do not come into contact with chemically aggressive substances.
  6. Low level of thermal conductivity.
  7. Easy maintenance. Due to the fact that the walls of the tubes are transparent, they can be easily inspected, if necessary, and also easily cleaned of contamination.

But keep in mind that all small-diameter plastic pipes are not suitable for transporting substances on an industrial scale.

Making transparent PVC pipes

In order to make PVC products, methods similar to extrusion and casting are used.In the first method, the plastic is heated and pressed through a special ring-shaped hole.

If we are talking about casting, the pipe is made in several stages:

  • First, the plastic is poured into a special mold on a centrifuge.
  • After that, the centrifuge is turned on and waited until the material is evenly distributed along the walls of the mold.

  • When the material cools down, take out the transparent tubes.

Note that it is not recommended to use transparent tubes for the pipeline, since there are more suitable specimens for this.

Features of PVC pipes

The described type of plastic rigid pipes of small diameter is used to create non-pressure systems. They can be used for transporting drinking water and other substances.

There are the following features:

  1. Special tools must be purchased for installation.

    The pipes are connected by cold welding. You can also connect the pipes with a rubber cuff.

  2. Pipes of this type are rigid and for their connection they use fittings, the same as for connection of metal products. For this reason, when designing systems, professionals make calculations such as for steel pipes.
  3. PVC products make it possible to carry out both internal and external laying of communications.

    But then, when creating an outdoor system, you can not worry about the appearance of the structure.

  4. Polyvinyl chloride products are cheaper. For example, plastic square pipes are very often used to create ventilation systems, whereas 20 years ago they would have used galvanized metal or ordinary.

Single-layer polypropylene pipes

In the building market you will find both multilayer and single-layer products. Pipes of the second type differ in that they contain nothing but polypropylene.

They are divided into several types:

  • PPH tubes are distinguished by their unique ability to be used in large temperature ranges, but unfortunately they poorly resistant to low temperatures. In addition, they are highly resistant to aggressive substances. These tubes are often used to transport liquids for technical purposes. Due to their thin walls, they are often used to create ventilation systems.
  • Variety PPB has high resistance to low temperatures and flexibility.

    Another characteristic that should be noted is a high level of thermal expansion.

  • Tubes of the type PP R are universal and can be used at any temperature. They are highly durable and can also retain their shape perfectly under all conditions. Since these pipes are environmentally friendly, they can be used to transport drinking water.

Features of multilayer samples

When creating on top of a thick-walled tube, foil is glued, which will then be covered with a protective layer of polypropylene.

Each layer is connected to each other through holes in the foil. Usually pipes with a length of 400 cm are used. Their outer diameter with this length can be from 1.6 to 12.5 cm.

You can immediately buy fittings, a plastic box and other parts in the kit. All elements can be connected using special equipment. You can find threaded fittings if desired, and then connecting small diameter plastic pipes to a metal water supply system is not difficult.

Such pipes can also be used to transport hot and cold water and as additional elements of the heating system. In addition, they are used for various pipelines for technical purposes.

Polyethylene products

Such pipes can withstand temperatures not lower than -22 O Celsius. Note that for models that have a diameter less than 6.3 cm, they are connected using fittings, and they can be made of polypropylene and brass. For larger diameters, a butt weld connection is used. They can be used when the pressure is high or even when there is none.

Often the free-flow option is used when it is required to make an internal sewage system.

Metal-polymer pipes

Inside the metal-plastic pipes, a layer of aluminum foil is inserted, which helps to reduce the coefficient of expansion. The main advantage is that the fold remains in shape. Most often, hidden installation is done. Do not forget that with such excellent characteristics, pipes are expensive, but they justify their cost with high quality and resistance to expansion.


Whichever type of small diameter plastic pipes you choose, with their help you can create a domestic water supply system that can be boldly use for more than a dozen years. But when choosing, you should choose the right type of pipe and install it according to the rules for carrying out such work.