Pipes

Fiberglass pipes. Methods of manufacture. Classification, marking. Installation

August 13, 2020

Fiberglass pipes - long hollow elements made of fiberglass with a constant cross section, which are intended for implementation of movement on them of any working environment or for protection are placed inside cables of various function. Production on an industrial scale has been established since the mid-1950s, but indeed widespread begins in two or three decades.

Fiberglass pipes are universal products, which have found application in many areas of construction and industry

Methods of manufacture

Fiberglass pipes are made on the basis of four technologies, radically different from each other. To obtain composite products are used:

1. Winding (winding). It relies on fairly high performance and extremely easy to perform. There are winding:

  • simple;
  • continuous.

The winding is divided according to the use of polymeric binders:

  • thermosetting - polyester, phenol-formaldehyde, epoxy and other resins;
  • thermoplastic - polyamide, polypropylene, polyethylene, polyethylene rephthalate, etc.. In this case, the technology is possible in one or two stages.

Reinforcing glass fiber is laid in different ways, but large-scale industrial production is only four:

  • spiral-ring. This is how high-pressure and structural fiberglass pipes are made, for cases of solid propellant rocket engines, pylons of power lines. Fiberglass pipes of large diameter in this way are practically not produced due to the high complexity and high cost of the process;

For the manufacture of pipes using different methods of winding and winding material

  • spiral tape. Simplification of the technological process allows to obtain products of large diameter. But it turns into a decrease in quality, in this way fiberglass pipes for highways with average or low pressure are made;
  • longitudinally and transversely. In this way, the fibers are stacked by machine independently of each other;
  • oblique longitudinal-transverse. The method was developed at the Kharkiv Aviation Institute, to mass-produce fiberglass shells for rockets.

Importantly! The latter method differs from others by obtaining the highest content of glass in the resulting product. It comes to 85 % of the total mass of fiberglass. Rarely used fiberglass winding is close to this method, with which small batches of large products are obtained.

2. Centrifugal molding (casting). This way, which allows to increase the thickness of the walls almost indefinitely, receive pipes with the increased ring rigidity, as well as products for microtunneling, exposed to high axial loads.

3. Pultrusion method (broaches). On high-performance equipment are performed for heating systems, plumbing pipes of small diameter and rods.

4. Extrusion method (extrusion). Simplification of technology to increase productivity to the highest level allows to produce from thermoplastics, mainly, products with non-continuous reinforcement, that is, with deteriorating physical and mechanical characteristics.

In addition to production technology, pipes differ in material composition, which affects the properties

Classification

High-strength composite products, depending on, which material is chosen as the reinforcing filler, happen:

  • basaltoplastic;
  • organoplastic;
  • fiberglass.

Take into account the type of polymeric binder, which can be:

  • polyester;
  • epoxy.

The type of connection matters:

  • adhesive;
  • mechanical.

Based on the design features of the walls, pipes are treated as:

  • multilayer;
  • lined;
  • without lining.

Pipes without protective coating (linings) used for transportation of non-aggressive environments

By design, the product can be:

  • single-layer. Manufactured using the wet winding method with a predominance of epoxy resin and flakes as a binder;
  • multilayer. They are hidden by one or more layers of polyethylene.

Useful Information! The use of resins increases the resistance of fiberglass pipes to acids, salts and alkaline solution.

The resin is used biphenol, isophthalic or orthophthalic.

Pipes are distinguished depending on the device of internal section, which happens:

  • continuous. The shape can be round, semicircular, rectangular, trapezoidal, segmented;
  • ring. These are performed in agreement with the customer.

Products may differ in the method of cutting reinforcement, strengthening the degree of the lateral face of the groove wedges.

Areas of application and marking of fiberglass pipes

The advantages of fiberglass products have led to their spread in various fields. Mass application was found in:

  • oil industry. Ability to maintain high corrosion resistance under the influence of aggressive environments (oil, solutions, formation waters) and high specific strength allow to give preference to fiberglass products before steel and polymer;
  • coal industry. Light weight and simplicity of installation play a role here, low flammability and flammability, non-toxicity of combustion products, corrosion resistance, no striking fragments in the methane explosion;
  • energy. Resistance to high pressure makes fiberglass necessary for pipelines;
  • housing and communal services. Sewerage and reclamation systems are equipped with fiberglass products, utilities.

Fiberglass pipes are suitable for installation of domestic water supply and sewerage systems

Label fiberglass products as follows:

  1. And - are intended for pumping of working environments with various abrasive inclusions;
  2. P - for hot water supply systems with energy temperature up to 75? WITH;
  3. P - for the water supply network, including, supplying drinking water;
  4. C - universal purpose. The working medium can have different acidity;
  5. X - able to transport chemically active liquids and gases.

Advantages and disadvantages of fiberglass pipes

The proliferation of fiberglass products is due to the following advantages:

  • duration of operation;
  • light weight, which simplifies transportation and installation;
  • low coefficient of thermal expansion;
  • ease of installation;
  • resistance to corrosion and inertness to aggressive environments;
  • durability;
  • strength;
  • resistance to temperature fluctuations in the range from - 65? From to +155? WITH;
  • relatively low cost;
  • environmental friendliness.

pay attention! There is such a lack of fiberglass products, as low stability at considerable loading, falling across the fibers, which leads to the formation of cracks. Therefore, to enhance the tightness of the inside is applied a special corrugated layer.

The advantages outweigh the disadvantages, which, rather, can be attributed to the peculiarities of use.

Installation of pipes can be carried out by a bell method, which is simple

Installation of fiberglass pipes

There are many ways to connect fiberglass products, that do not require special equipment and are not difficult:

  • clutch. The possibility of additional installation of structures with the use of adhesives is allowed, when no subsequent disassembly will be required;
  • toboggan. Considered as a kind of coupling, when the pipes are joined using a special device, and then connected by fasteners;
  • open pipe. Standard and extremely simple connection, in which the pipe is inserted into the extension of the next;
  • screw;
  • threaded;
  • flange. The ends of the pipes are equipped with flanges.

Fiberglass pipes are easy to connect, as no special equipment is required, no special skills.

Speed ​​of installation of fiberglass products in combination with advantages, provided by their use, contributed to the creation of sustainable demand in various spheres of economic activity. The use of fiberglass pipes in the domestic sphere has especially expanded.