From the variety of materials that are used to make polymer pipes for various purposes, Special attention Always pay attention to fiberglass, as it has truly unique performance properties. As a rule, fiberglass pipes are used more for industrial purposes and are distinguished by the fact that they easily withstand any operating conditions and have a fairly long service life. And, despite the fact that this material is relatively expensive, it is last years are becoming increasingly popular, including among ordinary private developers.

Fiberglass pipes

What are these pipes?

So, fiberglass is a special composite material, which is characterized by increased strength characteristics. Manufacturers of the pipes described in this article assure that their products, which are impregnated with epoxy/polyester resins, can be used for above-ground/underground installation of pipelines for various purposes. Such pipes perform well under conditions of increased pressure of the transported substance; they are used to lay pipelines in a wide variety of climatic zones (even the Far North is included here).

Note! If necessary, then inner surface products can be applied protective covering, thanks to which they can be used to transport various gaseous or liquid media.

Marking glass plastic pipes, which have similar coverage, looks like this.

1. "P". Such products can be used for cold water supply pipelines.
2. "A". Pipes bearing this marking are intended for moving liquid media that include various abrasive impurities.
3. "G". These are pipes that are used for laying hot water supply networks.
4. "X". Products that have this marking are designed for chemically active liquids, including products from the oil refining industry.
5. "WITH". The last category of pipes, which is intended for all other purposes.

Features of the appearance of fiberglass pipes

The production of this kind of pipes arose back in the 50s of the last century, since it was then that the production of epoxy resins acquired an industrial scale. This technology, like any other new product, was not particularly popular at first: people had no experience in using fiberglass, moreover, traditional materials (such as aluminum or steel) were relatively inexpensive.

However, after 10-15 years the situation changed dramatically. For what reason?

1. First of all, this is explained by the fact that the cost of steel and non-ferrous metals has increased significantly.
2. Fiberglass pump and compressor pipes had an advantage over steel ones - they weighed little and were resistant to corrosion (the pipes did not suffer from prolonged contact with salt water, which cannot be said about their “competitors”).
3. Another reason, which is largely related to the previous one, is that commercial development of gas/oil fields has begun to develop.
4. And finally, the production technology itself changed - now fiberglass pipes were cheaper and became more and more durable.

It is quite obvious that we did not have to wait long for results - by the end of the sixties, the Ameron company from the USA burst into the building materials market with high-quality high-pressure fiberglass pipes. Initially, the company's products won North America, and therefore moved to the Middle Eastern market. Already in the eighties, European countries entered the game, and some time later, the Soviet Union.

Video - Fiberglass pipes

Types of pipes depending on the type of resin

The performance properties of the pipes described in the article may vary depending on the specific resins they are made from. It is for this reason that during the purchase it is imperative to clarify what kind of fiberglass they are selling you. From this point of view, products are divided into two categories; let’s get acquainted with the features of each of them.

1. Fiberglass made from polyester resins. This material is characterized by chemical neutrality and resistance to the influence of various types of substances; the material is very important element when laying pipelines for the oil refining industry. However, you should be aware that such pipes are not suitable for use in conditions high temperatures(over +95 degrees) or high pressure (maximum - 32 atmospheres).
2. Fiberglass made on the basis of epoxy resins. Thanks to the epoxy resin used in the production process, finished products it turns out much more durable. Pipes made using this technology and having a larger diameter are able to withstand very high pressure (maximum - 240 atmospheres) and temperatures of no more than +130 degrees. Another advantage of this material is its relatively low thermal conductivity, and therefore there is no need for additional thermal insulation (the products practically do not give off thermal energy). The cost of such pipes is somewhat more expensive when compared with that of polyester fiberglass.

Where can fiberglass pipes be used?

Let’s immediately say that they can be used in a wide variety of industrial and economic sectors. But more specifically, such pipes have proven themselves excellent in the areas listed below.

1. Energy. Here, such pipes are actively used when laying pipelines operating at high pressure levels.
2. Oil industry. In this case, fiberglass pipes are used both for transporting valuable minerals ( we're talking about about main lines), and to ensure all other production processes, including for gas/oil production.
3. In the housing and communal services system. And here the products described in the article are used for laying water supply systems (DHW and cold water supply), as well as for installing heating systems.
4. Medical, chemical industry . Due to chemical neutrality, as well as resistance to various types of aggressive influences, fiberglass pipes are simply irreplaceable for transporting alkalis, acids and other mixtures/liquids.

Note! Among other things, in Lately Such pipes are increasingly used for domestic purposes. Moreover, this use is completely justified - their trouble-free (that is, without repair) service life is more than half a century.

Features of manufacturing fiberglass pipes

How are such pipes produced today? There are four main methods, we will look at each of them. But first, let us note that the performance properties of finished products can vary significantly depending on the number of structural layers.

1. The simplest single-layer pipes are considered the cheapest. And it’s not surprising, because fiberglass in this case is practically not protected by anything.
2. Double-layer products have an outer protective shell that increases resistance to UV radiation and various types of aggressive environments.
3. Finally, in products consisting of three layers, one layer is an additional strength layer - it is located between the outer and inner. Such pipes are very durable, and therefore can be used in very high blood pressure. However, it should be remembered that they are not cheap.

Now let's look at the basic manufacturing technologies.

Technology No. 1. Extrusion

In this case, the hardener is mixed with resin, as well as crushed glass fiber, and then the resulting mixture is forced through the hole using a special extruder. As a result, we get a technologically advanced and sufficient cheap production, however, there is no reinforcing frame, which affects the strength characteristics of the product.

Technology No. 2. Pultrusion

Here the products are formed between the outer and inner mandrels. Thanks to this, all surfaces come out perfectly smooth, but due to production limitations, such pipes cannot be manufactured with a large diameter or designed for increased operating pressure.

Technology No. 3. Centrifugal molding

The peculiarity of the method is that the reinforcement in this case is a ready-made sleeve made of fiberglass, pressed against the surfaces of the mold, which rotates due to centrifugal forces. Due to these same forces, the resin is distributed along the walls of the products as evenly as possible. But the main advantage is that you can get perfectly smooth outer surface. Although there is a minus - the technology is quite energy-intensive, and therefore expensive.

Technology No. 4. Winding

Here, glass fiber, which is impregnated with a binder, is wound onto a cylindrical mandrel. The equipment used for such production has become most widespread due to its increased productivity and simplicity.

Note! This method can be of several types. Let's look at the features of each type of winding.

The first variety. Spiral-ring

A special stacker moves back and forth parallel to the rotating mandrel. After each such pass, a layer of fibers remains, and the step is permanent. Thanks to this winding technique, extremely tear-resistant fiberglass pipes are obtained.

Note! What is characteristic is that if the thread is pre-tensioned, then the strength finished product because of this, it will also increase, and the risk of cracks during bending will be minimal.

Using this method, pump-compressor products are produced (they are able to withstand high operating pressures), various load-bearing elements(including supports for power lines), as well as housings for rocket engines.

The second variety. Spiral belt

It differs from the previous version only in that the stacker leaves a small tape consisting of several dozen fibers after each pass. For this reason (more passes are required), the reinforcing layer is not so dense. The advantage of the technique is that it uses simpler, and therefore cheaper, technology.

Variety three. Longitudinal-transverse

The main difference is continuous winding - both longitudinal and transverse threads are laid simultaneously. At first glance, the technology itself in this case should be simpler and cheaper, but there is one difficulty - a purely mechanical one. So, the mandrel itself rotates, and therefore the reels must also rotate (those from which the threads are wound). What is typical is that the larger the diameter of the pipe, the larger number you will need these coils.

Variety four. Transverse-longitudinal oblique layer

The technique was created in Kharkov back in Soviet times and was intended for use in the manufacture of rocket shells. Soon the technology was spread to other countries. The bottom line is that the stacker forms a wide tape, which, in turn, consists of numerous fibers that are impregnated binder. This tape is wrapped with non-impregnated thread even before winding - this is how axial reinforcement is created. After laying, each new layer must be rolled with a roller, which squeezes out excess binder and compacts the reinforcement.

This technique has important advantages; let’s look at each of them in more detail.

1. The production process is continuous, and the wall thickness can be any (only changing the overlap of the tape is required).
2. IN finished pipes there is quite a lot of glass fiber (this figure can reach 85 percent; for example, with other methods it is a maximum of 40-65 percent).
3. The performance indicator in this case is also quite high.
4. Finally, it becomes possible to produce pipes of the most large sizes(theoretically there are no restrictions at all), which depend solely on the dimensions of the mandrel.

Table. The main types of pipes described in the article.

Table. Diameter of casing and pump-compressor products according to GOST.

Table. Diameter of linear products according to GOST.

Key advantages of pipes made of fiberglass

What is the reason for such high popularity of such pipes? Below is a list of the advantages of this material - it is not too long, but each of the points is of great importance.

1. The cost of fiberglass pipes is more than acceptable, especially when compared with products made from stainless/high-alloy steel.
2. Thanks to one or another reinforcement scheme (all of them were listed in the previous section of the article), it is possible to obtain products that have specific mechanical properties. For example, the first type of winding (spiral-ring) makes it possible to produce pipes that are extremely resistant to high operating pressure.
3. Fiberglass is also characterized by excellent resistance to various aggressive environments and corrosion.
4. Finally, the material just weighs a little. More specifically, its specific strength is approximately 3.5 times higher than that of steel. Consequently, pipes made of these materials, having the same strength, will have completely different weights.

Approximate cost of fiberglass pipes

The modern range of products described in the article is quite large, and therefore there are many manufacturers. However, they all produce pipes in accordance with GOST standards, and therefore the dimensions and characteristics must be identical. But still, let’s get acquainted with the features of several types of pipes, and also find out today’s average market prices. For the convenience of visitors to our website, all information below is presented in the form of a small table.

Table. How much does fiberglass pipe cost - prices, characteristics.

Name, photo	Short description	Average market value, in rubles
1. Profile pipe fiberglass	The dimensions of the product are as follows - 10x5x0.6 centimeters (HxWxT). As for the weight, in this case it is 3.14 kilograms per linear meter.	From 1250 per meter
2. Fiberglass profile pipe	A similar product, only the dimensions differ (in this case they are 18x6x0.6 centimeters) and, therefore, the weight. The density in this case varies between 1,750 and 2,100 kilograms per cubic meter. Note also that the specific strength of this material is the same as high-quality steel.	From 2200
3. Corrugated fiberglass pipe	The dimensions of this product are 3.4 x 0.9 centimeters, and the weight is 500 grams per meter of length. The internal diameter of such a pipe is 2.5 centimeters.	From 200
4. Round pipe fiberglass	Her outside diameter is 7 centimeters, while the internal one is 5.5 centimeters. The walls of the product are 1.5 centimeters thick. The mass is 2.8 kilograms per meter of length.	From 1150
5. Round fiberglass pipe	In terms of characteristics, this product is very similar to the previous one - its outer diameter is also 7 centimeters, but the inner diameter is already 6 centimeters. The walls are centimeter thick.	From 800

Note! As you can see, the cost can be different and depends on the specific shape of the products, their dimensions and wall thickness. The price may also vary depending on the specific manufacturer, but not much. Be that as it may, there is plenty to choose from in any case.

Video - Advantages of fiberglass pipes

Summing up

In the end, it is worth noting that today we talked, of course, only about a small part of such a vast and interesting topic, such as the use of fiberglass (in particular, pipes made of this material). We have only briefly mentioned whether such pipes can be used in sewer or heating systems, are they better than plastic or, say, metal-polymer analogues? Be that as it may, we will return to this topic later. That's all, good luck with your work!

As is known, for the installation of hot water pipelines or heating systems, the use of standard polypropylene or polyethylene pipes impossible, since plastic is not able to withstand the required temperature load.

However, the use of more traditional products made of metals and alloys (copper, steel, etc.) is also undesirable - they are quite expensive and have too much weight, making installation and repair of the circuit difficult. In this case, it comes to the rescue modern solution– fiberglass reinforced polypropylene pipes, combining the lightness of plastic and the reliability of alloys. It is the RVK pipe that has these characteristics.

Pros and cons of polypropylene products

Advantages of conventional polypropylene (PPR) pipes:

• low cost - the price of such products is significantly less than products made from metals and alloys;
• strength;
• light weight - polymer products are much lighter than similar metal products;
• resistance to low temperatures;
• chemical neutrality to most aggressive environments - acids, alkalis, oil and gas products, saline solutions;
• no threat of corrosion.

Disadvantages of simple pipes:

1. A small value of the upper temperature threshold - polypropylene pipes begin to melt when they reach 175°C, and soften when the temperature in the system rises to 130-140°C. At first glance, this should not be a problem, since the operating temperature in the heat supply system is characterized by values ​​of 90-95°C; however, when two parameters are combined - high pressure and high operating temperature - the damage received by the pipes from the coolant becomes more significant, therefore, the risk of pipe damage increases.
2. Tendency to expand significantly with increasing thermal load. To a greater extent, this concerns the length of the product: the length of the pipes increases greatly, and wavy lines appear on the surface. This is not only unsightly, but also carries the threat of depressurization of the circuit or damage to wall or floor coverings, including cracking of fragile materials - plaster or cement.

This problem cannot be solved by conventional methods; even the installation of compensators is not entirely effective. The most logical solution is the use of glass fiber reinforced plastic pipes. Characterized by everyone positive properties high-molecular compounds, and in addition to increased resistance to high temperatures, these pipes can be used in almost any heating circuits and hot water supply systems.

Comparison of pipes reinforced with glass fiber and aluminum foil

To strengthen plastic pipes and give them thermal stability, two types of reinforcement are used:

• aluminum foil;
• fiberglass.

In this case, the aluminum plate can be used in various options: in perforated or solid form, act as an outer covering or be located in the middle of products, between layers of polymer. Fiberglass is certainly placed inside reinforced plastic pipes.

It should also be noted that aluminum reinforcement allows the product to withstand greater pressure within the system, so if the operating pressure is unknown or too high, it is better to use this option.

Characteristics of foil-reinforced pipes (designated PPR-AL-PPR):

• increased rigidity of products, resistance to mechanical loads and all types of deformation;
• thickness of the reinforcing metal layer – 0.1-0.5 mm (varies depending on the size of the pipe cross-section);
• the method of joining aluminum and plastic is glue, the quality of which determines the quality of the products;
• excellent tightness that does not decrease over time.

Installation of pipes with an aluminum layer is associated with some technological difficulties: before soldering or welding individual elements the metal layer at the ends needs to be cleaned. Failure to comply with this recommendation will lead to a rapid loss of structural integrity - due, first of all, to delamination of the polymer and metal during heat treatment, and secondly, due to electrochemical damage to aluminum.

Against the background of the problems listed above, polypropylene pipes with fiberglass look like a more acceptable solution:

• the reinforcing material is quite similar in nature and characteristics to the main polymer;
• there is no need to clean the ends before welding or soldering;
• During the heat treatment process, the glass fiber and alloy not only do not delaminate, but, on the contrary, form a more durable connection.

Based on this, a glass fiber reinforced pipe is in most cases perfect solution for designing pipelines of various technological directions.

Characteristics of glass fiber reinforced products

As you might guess, such products have three layers: two polypropylene and one reinforcing layer, consisting of the same material mixed with fiber fibers (fiberglass). Due to the almost identical composition, such a three-layer structure is almost equivalent to a monolithic one.

Characteristics of glass fiber reinforced polypropylene pipes:

• complete absence of threat of corrosion;
• remarkable smoothness of the internal surface of the products, resisting the accumulation of deposits and, as a result, the occurrence of blockages;
• increased mechanical strength of products;
• no threat to longitudinal or transverse deformation when the internal temperature of the system increases;
• chemical and biological neutrality - both to aggressive environments and to waste products;
• small hydraulic resistance therefore, the value of pressure losses is reduced to a minimum;
• good noise reduction;
• do not in any way affect the properties of the supplied water, therefore, they are absolutely safe for human health;
• long service life – with correct installation and operation – at least 50 years.

Concerning dimensional characteristics glass fiber reinforced pipes, the most popular diameters are:

• up to 17 mm – used for installing heated floors;
• up to 20 mm – for domestic hot water pipes;
• 20-25 mm - such pipes with fiberglass are used for indoor heating common use and when installing sewer risers.

To secure pipes of smaller diameter, plastic clips are sufficient; for products with larger cross-sections, it is necessary to use clamps.

Installation of fiberglass pipes

The connection of such products is carried out in the same way as conventional plastic pipes.

There are three ways to fasten products:

1. Using threaded fittings.
2. Using cold welding(that is, special glue).
3. Thermal welding (soldering).

The first option is made as follows: the end of the pipe is pulled onto the fitting of the connecting element and crimped in a circle with a mounting nut. The connection is not inferior in reliability (strength and tightness) to the third method; it can be used even when constructing pressure-type pipelines. The only drawback is that if you apply excessive force when tightening the mounting nut, it can simply burst.

In the case of cold welding, the glue used ensures quick creation of the joint, but not reliability. When installing, apply to the inner surface of the polypropylene coupling adhesive composition, then the end of the pipe to be connected is inserted there; the connection is held motionless for some time so that the glue has time to harden.

When welding with welding machine the surfaces of pipe ends and couplings are heated; after joining they form a single polymer mass. This connection is the most durable and airtight.

In general, the use of fiberglass reinforced pipes is completely justified, convenient and beneficial with economic point vision.

Fiberglass pipes are an excellent alternative traditional materials such as steel, and concrete. They have excellent strength, corrosion resistance, are lightweight, and easy to operate and install. They have a smooth surface that allows for higher flow rates, which reduces energy consumption.

Fiberglass is a common type for fiberglass. The fibers can be randomly placed, pressed into a sheet, or woven into a fabric. The plastic matrix may be a thermoset polymer matrix, most often based on thermoset polymers such as epoxy resin, polyester resin or vinyl ester.

Story

From the mid to late 1980s of the 20th century, the production and use of underground composite pipes began to grow large diameter. Technological advances in the filament winding process, corrosion resistance, and strong market factors have contributed to the popularity of fiberglass pipe. Definitions of what constitutes a large diameter pipe can vary, but in general sizes range from 12 to 14 inches.

Composite or fiberglass pipe is used in a wide range of industries such as power generation, petrochemicals and desalination sea ​​water. Fiberglass pipe is corrosion resistant and has a large life cycle, which often exceeds 30 years, and is a better alternative to steel and other metal alloys, ductile iron and concrete. According to statistics, more than 60,000 km of large-diameter pipes are in operation worldwide.

Application area

Main areas of use:

Thermal expansion and contraction

The fiberglass pipe has different diagonal and axial directions. In the circumferential direction the thermal expansion is approximately the same as that of steel. However, in the axial direction the thermal expansion is approximately twice that of steel.

The relatively low weight of fiberglass pipe is an advantage that should be taken into account when designing a piping system. Since thermal forces are smaller, the restraining equipment (guides, anchors) does not need to be as powerful and heavy as for steel pipelines. There is some increase due to the finite pressure load on the piping system, but experience has shown that this change in length does not need to be taken into account when designing a fiberglass piping system. Composite piping systems can handle thermal shock between maximum rated operating temperatures if the pipe connections are not mechanical.

Characteristics

Fiberglass pipes have the following advantages:

• long service life due to excellent resistance to corrosion and chemical attack (salt water, CO 2, H 2 S, solvents, thermal and oil water);
• ease of handling and light weight (approximately ¼ the weight of steel);
• require less personnel and equipment for installation;
• quick installation thanks to fittings and reduced installation costs;
• Improved flow characteristics due to smooth internal lining and reduced material resistance.

Fiberglass pipes: technical characteristics

The main reason for the increasing use and popularity of fiberglass is the key benefits such as high strength-to-weight ratio, dimensional stability, good mechanical properties, ease of installation, reduced installation and maintenance costs and overall durability in extreme conditions. Another benefit of fiberglass pipe is that it has a smoother interior surface than traditional building materials. The smooth internal bore resists large deposits and can produce high service fluid flow throughout the life of the project.

When designing a large diameter underground pipe, many considerations must be taken into account: local soil conditions, depth groundwater, burial and live loads, deflection due to error and operating temperatures, fluid velocity and pressure, head loss due to turbulent flow, hydraulic hammer, bending pressure and pulsation pressure. Designing a proper underground piping system is a complex process that involves extensive calculations - product design should always be carried out by qualified engineers.

Composite fiberglass pipe

Fiberglass uses a variety of epoxy and vinyl ester resins and, if necessary, corrosion barriers to achieve optimal performance. performance characteristics for any practical application. A wide range of temperatures and pressures allows you to best match the fiberglass pipe to the requirements of a specific application.

High-pressure fiberglass pipes are time-tested as they have been used in harsh environments for decades and have proven their durability and value. The first samples appeared more than 40 years ago.

Advantages of fiberglass composite piping systems:

• increased resistance to corrosion/abrasion when exposed to strong acids;
• high strength;
• pipe spans are similar to steel counterparts;
• high quality PVC for higher temperatures and longer piping distances;
• optimal replacement for steel pipes with external or corrosive internal coating.

Fiberglass pipe diameters range from 1 to 72 inches.

Microbiologically induced corrosion

This vulnerability is a common problem in industrial processes due to the presence of microbes. This eventually leads to the formation of gaps, with pockets of oxygen and ion concentrations, allowing corrosion to progress.

If not treated with a fiberglass repair kit, piping systems will be significantly weakened, often creating holes in the pipe walls, leading to leaks and loss of fluid.

Treatment can be done by protecting the pipelines or chemically treating the fluid, which itself may be susceptible to corrosion.

Either of these methods requires additional costs, which may only delay failure.

Fittings and accessories

Fiberglass pipe accessories are made from epoxy and vinyl ester resins. These adhesives provide the best corrosion resistance and temperature performance.

Fittings include flanges, couplings, tees, reducers, drainage pipes, repair kits, fiberglass repair kit and much more. Fiberglass pipes are designed for harsh operating conditions and are suitable for wide range chemicals specified in the fiberglass chemical resistance manual.

All fittings come with a pipe or flange connection for easy field installation. Prices for fiberglass pipes include all accessories necessary for installation and range from 4,350 to 47,900 rubles per linear meter, depending on the diameter.

Modern residential plumber Baker Glenn I.

Ceramic and fiberglass pipes

Ceramic and fiberglass pipes are used as sewer pipes. Both types of pipes are considered rigid and are installed using fittings and sealants (Table 3.4). Ceramic products, similar to tiles, are products made from densely sintered clay. Such pipes are hard, heavy, brittle and difficult to install. Due to their heavy weight, they are available in short lengths of 2 (0.61), 4 (1.22) and 6 feet (1.83 m), making them easy to install. Although the short length of the pipes makes it difficult to slope them properly in the trench, they are impermeable to bulk waste and resistant to corrosion and deposits.

Table 3.4. Characteristics of ceramic and fiberglass pipes

Note. Both ceramic and fiberglass pipes should not be located within 5 feet of the home.

Fiberglass pipes are typically made from fiberglass and asphalt resin. Light weight and long length are the advantages of the produced pipes, which are easily given the desired slope in the trench. Pipe lengths typically range from 8 (2.44 m) to 10 feet (3.05 m). Such pipes, compared to ceramic ones, are much easier to install. In many areas, ceramic and fiberglass pipes are being replaced by PVC pipes. However, you may encounter them when repairing sewer lines in older homes.

In most cases, repairs can be made using PVC pipes and flexible couplings, as shown in Fig. 3.12. The components of such connections are couplings, fittings for sleeveless connections and clamps for fastening joints. These joints are made from thick rubber or neoprene fiber, similar to the material used in car tires. When purchasing a clamp or coupling, you must select the size that is appropriate for the diameter of your pipe. The clamp is completely placed over one of the pipes, which is then laid in place. Once both pipes are in place, you place the clamp on the second length of pipe and tighten the clamps. This type of connection allows for quick and easy pipe repairs, but should not be used for pressure pipe repairs.

Rice. 3.12. Elastic couplings and clamps are used to connect drain pipes