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Cranes for connecting polyethylene pipes with compression fittings. Compression polyethylene fittings for plastic pipes. Complete set of compression fittings

They allow you to reliably and make connections without the use of special welding equipment for connection plastic pipes. The connection of plastic pipes in this case occurs by a crimping method.
The advantage of compression fittings is the simplicity and ease of installation. There is no need to pre-prepare the connected pipes for installation. No special skills are needed to assemble compression connections, compression fittings are supplied ready for installation, assembled and complete.
Compression fittings have another important advantage - such connections are collapsible, and this allows, if necessary, quick dismantling or alteration of the pipeline system. Installation of polyethylene fittings can take place in almost any weather conditions, including at low temperatures.

Description and technical characteristics of compression fittings

Compression fittings are designed to connect pipes in drinking pressure and technical cold water supply systems, as well as in pipeline systems with a working medium, in relation to which the chemical resistance of products is ensured. Compression connections have different working pressures according to the marking.

Compression fittings are made of durable polyethylene and polypropylene. Polyethylene fittings with threaded transitions are joined with metal products and products from other materials that have the appropriate inch thread.
Polyethylene compression fittings reliably connect pipes made of the following materials:
- HDPE (PE80, PE63, PE100, etc.)
- PPRC (polypropylene type 3 - cold pipelines)
- PEX (cross-linked polyethylene - cold pipelines)

A short list of compression fittings for connecting plastic pipes

Fitting name	Picture	Existing dimensions (diameter, mm)
Coupling for pipes of the same diameter		20,25,32,40,50,63,90,110
Reducer for pipes of different diameters		20-63
Coupling with external thread for changing from plastic pipe to metal		20 x 1/2" ... 63 x 2"
Coupling with internal thread for changing from plastic pipe to metal		20 x 1/2" ... 63 x 2"
Branch (elbow) for changing the direction of the pipeline		20,25,32,40,50,63,90,110
Branch (elbow) with internal thread for changing the direction of the pipeline with a simultaneous transition to a metal pipe		20 x 1/2" ... 63 x 2"
Branch (elbow) with external thread for changing the direction of the pipeline with a simultaneous transition to a metal pipe		20 x 1/2" ... 63 x 2"
Tee for the production of a branch of a plastic pipe		20,25,32,40,50,63,90,110
Tee with external thread for the production of a branch with a simultaneous transition to a metal pipe		20 x 1/2" ... 63 x 2"
Saddle for connecting a branch plastic pipe to an existing pipeline		63 x 25, 110 x 32, 110 x 40
Saddle with female thread for connecting a branch metal pipe to an existing pipeline		25 x 1/2" ... 315 x 4"
Connection with built-in ball valve		20 x 20, 25 x 25, 32 x 32, 40 x 40
Connection with female thread with integrated ball valve, with simultaneous transition to a metal pipe		20 x 1/2", 25 x 3/4", 32 x 1", 40 x 1 1/4", 50 x 1 1/2", 63 x 2"
Flange connection for transition from plastic pipe to pipe fittings flange connection		50 x 50, 63 x 50, 110 x 100
End cap for permanent or temporary sealing of the pipe end		20,25,32,40,50,63,90,110

Complete set of compression fittings

Compression fittings are complete products. This means that all elements of products are interchangeable only within the same type of product group.
It must be borne in mind that the split ring, designed for axial fixation, is made of strong but brittle polyamide. If it fails, the compression fitting must be disposed of.
Sealing collar Made of EPDM (rubber-like plasticized polyethylene) material. The body of the compression fittings is made of polypropylene. To give additional strength to products with internal threads, certain types of couplings and saddles may have an external reinforcing steel cage.

Storage of polyethylene compression fittings

Compression fittings must be stored indoors, protected from direct sunlight. Storage at negative temperatures is possible without restrictions. When storing compression fittings in heated rooms, it is not recommended to place them at a distance of less than 1 meter from heating devices.

Installation and use of compression fittings

Compression fittings are mounted without the use of special tools (small diameters) or with special wrenches included in the product range. Installation instructions for compression fittings are given below.
The thread of the compression fittings must be sealed with FUM tape, the tightening torque of the threaded connections must be controlled so as not to subject the connections to additional mechanical loads.

Installation instructions for compression fittings

The method of connecting HDPE pipes with diameters from 20 to 50 mm.

Pipe preparation.

Mounting.
The pipe is inserted into the compression fitting up to the mark. ATTENTION! The pushing force of the pipe must be significant, otherwise it means that the pipe has not entered the rubber seal. The union nut of the compression fitting is tightened to the end of the thread.

The method of connecting HDPE pipes with diameters from 63 to 110 mm.

Pipe preparation.
The pipe is cleaned of dirt. The pipe is cut off even cut, perpendicular to the axis of rotation.

Compression fitting preparation.
The compression fitting is disassembled, while removing: rubber sealing ring; resistant glass; split fixing ring.

Assembly.
Stage 1 - pre-assembly.
Assembly takes place without a split ring. A rubber ring and a thrust cup are mounted on the pipe. The pipe is inserted into the body of the compression fitting and a rubber sealing ring is filled into the gap. The ring is recessed as much as possible into the body and the thrust cup is pushed forward. The coupling is additionally pushed onto the pipe until it stops. The union nut is screwed on and screwed with a special key until it stops. In this case, the thrust cup settles into the housing.
Stage 2 - final assembly.
The cap nut is removed. The split ring is put on the side of the pipe and shifted to the coupling. The union nut is screwed in with a wrench until it stops.

Installation of compression polyethylene fittings with an existing transition to a metal pipe.

Compression fitting preparation.
The compression fitting is partially disassembled. The union nut is unscrewed by 3-4 turns.

Preparation of plastic pipe.
The pipe is cleaned of dirt. Using a beveler or a sharp knife, cut the outer chamfer on the pipe. At the initial stage of work, it is necessary to mark the pipe: note the depth of the pipe entering the body of the compression fitting. Before installation, it is advisable to moisten the pipe with water or liquid soap. In some cases, grease is applied to the rubber ring of the coupling.

Preparation of a metal pipe.
The pipe is cleaned of dirt. A thread is cut into the pipe and sealing material is wound (FUM tape, linen, etc.).

Mounting.
The plastic pipe is inserted into the compression fitting up to the mark. ATTENTION! The pushing force of the pipe must be significant, otherwise it means that the pipe has not entered the rubber seal. The union nut of the compression fitting is tightened to the end of the thread.
The metal pipe is screwed into the threads of the compression fitting.

Operating conditions and safety measures

The pipeline with connections using compression fittings is used at ambient temperatures not exceeding + 40 degrees Celsius. It is possible to operate the pipeline underground and in the aquatic environment. Compression fittings are collapsible. It is recommended to install pipelines with compression fittings in such a way that they can be accessed during operation.
The connection of plastic pipes with compression fittings is durable (the service life is comparable to the service life of plastic pipes) if the connection is constantly in a humid environment and is not exposed to unacceptable chemicals and high temperatures.

Our Company offers various types of plastic pipes for sewerage, plumbing, heating, as well as connecting fittings to them. with an assortment and technical specifications You can find it on the website page.

When assembling or repairing a water main from polyethylene pipes, in areas of branching, bending and connecting pipes with different diameters, mechanical and welded fittings are used. They are focused on the requirements of GOST 27077-86, and include the following types of products:

For gasket gas pipes: fittings of thermistor and cast type.
For water supply: compression (collet, clamp), segment welded and flange type.
For drainage system: corrugated type.

Design features

According to their functional features, fittings are divided into the following types:

Tees (for joining 3 elements of the pipeline): even for connecting pipes with the same cross section and reductive (transitional) for products with different diameters.
Elbows (change the direction of the line at a given angle).
Couplings (for joining pipes in a stationary state).
Crosses (to form a single system of four products or divide the channel into 4 branches).

Compression fittings

They are used when installing external water supply (drinking and irrigation purposes) with a diameter of 110 mm or more. The catalog of fittings is represented by couplings (equilateral and transitional) with internal or external thread, elbows, adapters and plugs.

The main structural elements include:

Body part.
Cover with nut.
Sealant.
Clip of round section.
Pressing sleeve.

Compression fittings provide crimping with a ferrule and sleeve. The ring prevents breakout during hydraulic shock and vibration.

Positive characteristics:

Eliminate the need for special tools.
They give flexible and rigid properties to the fastening.
Quickly and easily mounted.
Available in a wide range of parameters and raw materials used.

Cast connections

Cast fittings are integral structures obtained under pressure with further mechanical processing. They are used for laying water and gas pipelines. Allow to carry out turns and branchings, to make docking of pipes with different parameters. It is allowed to connect cast clamps with welded clamps.

Butt-welding technology is used to connect to the pipe - the ends are aligned and melted, the formed joints withstand pressure, similar to a PE pipe.

An additional method of docking is the use of welded couplings. Cast fittings have an extended shank for mounting thermistor couplings.

Electrofusion joints

Represented by a series of connecting elements, for the fixation of which the technology of melting the upper part of the contours and walls of the fittings is used with the help of a heating coil inside the connecting element. They belong to a low price category and are used in a limited space. The limiting pressure range reaches up to 25 atm. Temperature conditions up to 40 gr. The connection to the pipeline is carried out by butt welding.

Segment fittings

They are formed under the influence of HDPE 80 welding. They are used in branched water pipes.

Thermistor connections

Principle of operation: welding equipment is connected to the outputs of copper windings located inside the structures. The passed current heats the winding, the fitting melts, connecting with the pipeline. The disadvantages include the high cost and the need for special welding machines.

Flange clamps

Docking circuits with fittings using flanges contributes to the tightness of the pipeline and prompt assembly / dismantling of the system. It facilitates the technology of connecting different containers, equipment and mobile mechanical elements. Paronite gaskets are used as seals.

Corrugated pipe fittings

When connecting elements of a water main and a non-pressure sewage system, welded corrugated pipe fittings are successfully used. To prevent displacement of the pipe during installation, a special rubber compressor located in the inner part of the bell.

Fitting diameter

The dimensions of the connecting elements directly depend on the parameters of the pipes, their throughput and wall thickness, but a number of nuances should be remembered:

Thick products. Marking allows you to find out the outer diameter of structures, without taking into account internal parameters. And thick walls affect the decrease in the parameters of internal patency.

Surface roughness. The internal coating of PE pipes is characterized by high levels of smoothness. This helps to speed up the transport of fluid and reduce the level of plaque formed.

Due to the increased wall thickness, the most popular option is a diameter of 20 mm or more. When compared with metal-plastic pipes, then the most requested parameters correspond to the number 16.

Common fittings and pipes made of PP include products with parameters of 20, 25, 32 and 40 mm. The maximum size threshold includes 110 mm, but it is in little demand.

Tip: for a water supply system in private construction with an optimal number of draw-off points, pipes with a cross section of 20 mm will become an actual solution.

Pipe joining technology

The connection of PE pipes is carried out by 2 methods: welded and detachable. The welding technology consists in the fact that the ends of the circuits are preheated to viscosity, connected and subjected to pressure until they completely merge with respect to each other. After performing welding work in compliance with the temperature and requirements, a strong monolithic seam is obtained. This technology is used for structures with a cross section of 50 mm.

The detachable technique is performed using compression-type clamps, made of brass or plastic. The need for constant monitoring of the connection eliminates the possibility of its use in hard-to-reach areas, so it is more often used in residential buildings where a large number of twists and turns. If it is necessary to lay a non-pressure pipeline or gas lines, this technique is the simplest and most economical. The exclusive advantage is that there is no need to use welding machine, special experience and knowledge. Installation can be done by hand.

Mechanical (split) fittings

Clamp fittings are used for technologically simple and cost-effective creation of predetermined line configurations of any complexity. For the repair and laying of water pipelines, structures with a diameter of 20-110 mm are used.

This is due to the inability to connect thin-walled structures end-to-end and the high cost of socket and thermistor welding methods.

Structurally, the joints are equipped with clamping parts and replaceable body parts (elbows, triple ramifications, etc.).

The flare nut is connected to the body by crimping the collet.
The toothed collet covers the PE contour and pulls it up to the body part.
The thrust ring transmits the tightening power of the nut to the O-ring.

The products of a number of manufacturers are represented by a single design of a collet and a thrust ring. The seal in the form of a ring provides reliable sealing of pipes along the outer cross section. The housing is equipped with internal stops that prevent the movement of pipes in the connection. The parameters of the product are indicated on the body part.

Material selection

The body part and the nut are made of PP, the toothed collet is made of solid polymers: POM (polyoxymethylene) or PPO (polyphenylene oxide). The seal is made of durable and flexible NBR rubber.

During the operation of products, with an increase in temperature, a lower pressure is provided, which is due not to the strength characteristics of the joints, but to PE pipes. With an increase in the level of heating, PE becomes softer, pipes can come out of the tee or elbow with insufficient axial force.

The table indicates the working pressure, but in practice a short-term increase is possible.

Standard set of fittings includes:

Solid systems are complemented by tank connections, adapters for metal pipes, adapters and tees. Tank connections are used for quick and reliable connection of the PE circuit to a container (made of plastic or metal) for liquid media.

They are presented in the form of a coupling with an extended thread, a plastic nut and a seal. Sealing is provided not on the thread, but on the surface of the tank.

Adapters for metal pipes provide easy connection of polymer threads or PE contours. Adapters are available only for pipes with a cross section of 15-28 mm.

brass connections

In terms of quality, they are comparable to PP fittings and have a similar device. The key advantage is the ability to connect with "bad" metal threads and reusable.

The toothed collet is made of metal or plastic. The first option is used for clamping PE and PP structures. For installation, a conventional wrench. In terms of cost, polymer fittings win 1.5-2 rubles.

saddles

They often replace tees when necessary to branch out the water line. This makes it faster and more economical. But the contour following the saddle outlet will have smaller parameters. For uniform flow division, a tee is required.

Saddle outlets are presented in the form of polymer clamps with a side outlet (threaded connection inside the pipe). A coupling with an external thread or a shut-off valve is screwed into the outlet. Branches correspond to parameters of standard pipelines: 25 - 315 mm. If the threaded outlet is equipped with a steel ring that prevents rupture if incorrectly installed, it belongs to the series of reinforced fittings.

Threaded connection adapters

The product range includes:

This includes transitions from external to internal threads and vice versa. "Bushi", "futorki" and "cuttlefish" provide a transition between threads of different sections and thread. They turn the clamping threaded socket into an elbow. However, a large number of adapters can harm the system: the best solution would be a line of 1-2 threaded connections.

Fitting cost

Fitting prices have little effect on the overall price of a pipeline. For example, a threaded coupling d = 25-32 mm has a cost similar to 1.5-2 m of pipeline. A similar coupling Ø 6.3 cm is comparable in cost to a 2.5-3 m pipe, and Ø 11 cm is comparable to a 4 m pipe. Fittings with such parameters are more expensive than thermistor clamps.

Video

The modern plumbing market provides many pipes from various materials, which are used for laying sewers, water pipes and other similar systems. Pipes made of different materials differ not only in their characteristics, but also in the way they are connected to each other.

Plastic pipes have several similar connection methods, but they all differ in their strength and ease of execution. In this article, we will analyze in detail all types of polyethylene pipe connections, as well as their advantages and disadvantages.

Introduction to the material

To begin with, it is worth disassembling the two main properties of polyethylene, from which pipes are made. Its first property is plasticity. Turning to GOST, you will see that the elongation coefficient of the material at break is 250%, but in reality this figure can reach 500-600%.

Such a high rate of plasticity is not always a plus. Thin polyethylene pipes will not withstand high pressure, and the threads cut on them for connection will completely make them inoperable, so it will not work to connect them with a thread.

The second property of polyethylene is fusibility. It allows you to weld pipes, because they begin to melt at a temperature of only 105-110 ° C. Here you can also find a significant drawback of these pipes - a low operating temperature limit, because the pipes soften at a temperature of 80 ° C, so it is impossible to use them for transporting hot liquids.

Having learned these properties, we can conclude that compression fittings for polyethylene pipes, as well as welding with a soldering iron, are the best solution for assembly sewer systems. Next, we suggest that you familiarize yourself with all the connection methods in detail.

Butt welding

Despite the fact that fittings for PE pipes make it possible to achieve a reliable connection, it is not always advisable to use them. So, for example, pipes of wide diameter are connected strictly by butt welding, because large fittings cannot be quickly attached to the pipe after desoldering.

When assembling lines from pipes of large diameter, specialists use heating devices that melt the ends of two pipes, after which they allow them to cool down, turning them into a single whole. The result is a reliable connection, the strength of which is equal to 90% of the strength of the pipe itself, which is quite enough for highways with walls several centimeters thick.

Connection with welded fittings

AT this case fittings are used for welding polyethylene pipes, which differ from similar products for polypropylene pipes only with your material.

The connection is made according to the following instructions:

Cut the pipe so that the resulting end is perpendicular to the axis;
Chamfer the outside of the pipe and inside the fitting so that the connection is made without various irregularities;
Choose a soldering iron nozzle that is suitable for the diameter;
Select the correct nozzle heating temperature, bearing in mind that the melting point of polyethylene is approximately 50°C lower than that of polypropylene;
Next, put polyethylene pipes and fittings for water supply on the soldering iron;
Now you can insert the pipe into the fitting, however, you must not turn the pipe, otherwise this will lead to the formation of peculiar waves that will reduce the strength of the connection, as well as create a slight resistance to the flow of water.

Electrofusion connections

This method of connection is also based on the weld fittings described above, however, here you do not need a soldering iron. Such a connection of polyethylene pipes is made with fittings with a built-in metal spiral, which has a high resistance electric current. Under tension, this spiral heats up strongly, melting the fitting.

Work should be carried out according to the following instructions:

Assemble all planned pipeline;
Connect the step-down transformer to the mains or use a car battery;
Connect the terminals to the coupling (details: " ");
Wait for the time required for it to melt (may be indicated on the fitting or instructions for it), after which, do this work with all other electric couplings.

Compression fittings

Such fittings for polyethylene pipes completely solve the above problem. The compression fitting is a simple but independent system that consists of the following components:

plastic case;
Sealing rubber bands;
Tightening nuts.

Assembling such a system is quite simple:

Insert the pipe into the fitting, after lubricating it with soapy water;
Tighten the tightening nut securely, which will press the sealing rubber.

There are many advantages to such a connection, but we will highlight two main ones. The first advantage is the ability to disassemble and reassemble the finished pipeline system. This possibility is especially relevant when using a boiler or a cleaning filter. The second plus of compression fittings is the ability to assemble the system without any auxiliary tools.

There are also some obvious downsides. For example, such connection fittings for polyethylene pipes have a short service life, because the tightness of the connection depends entirely on the state of the sealing gum, which over time may lose its elasticity.

Conclusion

It is impossible to make a final choice between all the above methods of connecting polyethylene pipes, because each of them has important benefits, for example, welding is high reliability, and compression connections are easy to maintain, so you will have to make the final choice yourself.

Polymer pipelines are a modern analogue of cast iron and steel communications. They are characterized by higher resistance to negative external influences, resistant to clogging, corrosion and temperature extremes. To connect these pipes, special PE fittings are used, which provide a tight and durable connection. They are widely used in heating and water supply systems. Communications made of these materials have long term operation, aesthetic appearance. Since the components of the pipelines are light in weight, there is no need to use powerful lifting equipment during their installation.

The production of these elements is carried out in several ways:

by processing raw materials with nitrogen compounds;
peroxide method;
by silane gas treatment technology.

Regardless of the production technology, finished products meet high performance requirements.

Advantages of polyethylene fittings

The advantages of these shaped elements include:

the absence of toxic components in the composition;
resistance to deforming mechanical loads;
chemical inertness;
resistance to pest damage, rotting and destruction under the influence of moisture;
wear resistance;
ease of installation.

To order connecting fittings for polyethylene pipes, contact the managers at the phone numbers listed on the site or use the web form.

Compression mounting technology has several advantages:

allows you to create a flexible and rigid connection;
eliminates the need to thoroughly align HDPE pipes;
ensures complete tightness of the polyethylene water pipe;
does not require the use of a welding machine and the presence of special skills;

The design of compression HDPE fittings includes a body, a cover, pressing nuts, sealing and ferrules. For the production of these elements, polypropylene copolymer, acetal resin, food-resistant rubber and stainless steel are used. The materials comply with sanitary standards and are suitable for drinking water supply.

The connection of HDPE pipes using compression fittings is called collapsible, because such a design can be assembled and disassembled several times. For installation, it is necessary to cut the pipe at a right angle, chamfer it and insert it into the connecting piece until it stops. Then, using a compression wrench, tighten the press-in nut as much as possible. As a result, the crimp ring is tightly fixed on the segment and ensures a tight connection.

Compression HDPE fittings from OptiPlastic

Our online store presents products from reliable manufacturers: Kokhanovsky Pipe Plant (Belarus), Georg Fischer (Switzerland) and SAB (Italy). We have established partnerships with suppliers, so we can offer the best prices and delivery times.

The catalog includes about 200 items of fittings of various diameters:

plugs, couplings, bends, tees Ø 20-110 mm, PN 10;
flange connections Ø 50-110, PN 10;
threaded saddles Ø 20-315, PN 10 and 16;
ball valves Ø 20-63, PN 10 and 16;
keys Ø 20-75 and 63-110.

Fittings are suitable for creating plastic plumbing systems from any grade of PE. If a the right dimensions are not in the catalog, we will arrange their delivery as soon as possible. You can pick up the goods yourself from warehouses in Moscow, Klimovsk and Novomoskovsk or order delivery in Moscow and the Moscow region.