How to install metal-plastic pipes - detailed instructions

Hello friends!
How are you? Let's talk about metal-plastic pipes, or rather about their installation. Metal-plastic pipes are used in almost all communication systems: plumbing, heating, intended for transporting compressed air and chemical media, including aggressive ones, and they are also used for laying electrical cables and wires.

Metal-plastic pipes have a number of valuable qualities, including strength, durability, and resistance to aggressive environments.

Installation of metal-plastic pipes

Combined pipes made of metal and polymers consist of five layers. The outer and inner layers are made of cross-linked polyethylene, with an aluminum shell between them. The layers of polyethylene and aluminum are held together with bonding adhesive layers.

This design provides metal-plastic pipes with a number of advantages:

• polymer layers have high corrosion resistance, providing aluminum with protection from moisture and exposure to aggressive environments;
• The aluminum layer makes it easy to install metal-plastic pipes with your own hands, thanks to the ability to maintain the shape that was given to the pipe.

The diameters of metal-plastic pipes vary between 16-32 mm. Installation of certain types of such pipes can only be carried out using fittings from the same manufacturer, while some are universal in this regard and allow the use of any fittings.

Advantages and disadvantages

Connecting parts for HDPE pipes have the same advantages that are inherent in all polymer products:

• Light weight.
• Wide range.
• Relatively low price.
• Easy to use and install.
• Antibacterial effect.
• Resistance to aggressive chemicals.
• Dielectric properties.
• Absolute corrosion resistance.
• Good elasticity, due to which the fittings are not affected by water hammer.
• Low thermal conductivity.
• Wear resistance.
• Smooth inner surface that offers little resistance to flow.
• High strength.
• Frost resistance. In case of freezing, polyethylene does not deform or crack.
• Excellent sealing of joints.
• Long service life - from 50 years.

The disadvantages of such products include:

• Vulnerability to ultraviolet radiation.
• Low melting point of plastic.

Methods for connecting metal-plastic pipes

The elements of a metal-plastic pipeline can be connected using two types of fittings:

In the latter case, crimp couplings or push-in press fittings can be used.

When using press fittings, a tool for installing metal-plastic pipes is required - press pliers, which can be mechanical or hydraulically driven. Mechanical pliers are usually used for household needs, while hydraulically driven pliers are used for professional purposes.

Regardless of the type of fittings, you will need the following tools:

• tape measure,
• pipe cutter,
• calibrator,
• for a sliding press fitting – expander,
• wrench.

Application

Crimp-type connections are used for installation of cold and hot water supply systems, heating systems, heated floors, and for transporting water for household needs, for example, for irrigation.

The following types of compression fittings can be found on the market for connecting steel pipeline components:

• valves;
• crosses;
• corner tees (three-dimensional)
• tees with transitions;
• simple tees;
• corners with transitions;
• corner;
• transitions from diameter to diameter;
• plugs;
• straight couplings.

Sewage pipes made of polyvinyl chloride (PVC) are also connected using crimp couplings, but such fittings should not be confused, since they have significant differences.

Steel pipes come in different diameters and are used for pipelines for various purposes.

Installation of metal-polymer pipes using compression fittings

The essence of the action of compression fittings is to create pressure when screwing the nut onto the open ferrule. This creates a strong compression joint that requires two wrenches to create.

It is advisable to install a metal-plastic water supply in one piece without unnecessary connections from the collector to the plumbing fixtures. This measure is due to the fact that with a compression connection, the fittings must be periodically tightened to maintain the tightness of the connection.

If screw fittings are located under the floor or behind tiles, then tightening them is either problematic or impossible.

How to choose?

Compression fittings for a metal pipe should be purchased based on the basic parameters (flow capacity, withstand pressure, temperature of the transported medium). This increases the reliability of the connection. It is also recommended to pay attention to the following factors:

• the material from which the fittings are made - steel products are cheaper, but last less than cast iron ones;
• the material from which crimp rings are made can be metal (relatively flexible, which will allow it to deform when tightened under the influence of union nuts), polymer material, but such products last less because they are more susceptible to the negative effects of high and low temperatures ( the limit temperature for these elements is up to +95°C);
• operating conditions: it is important to pay attention not only to the indicators of the transported liquid or gas, but also to the environmental parameters, since not all types of connecting elements can retain their properties when exposed to extremely low and high temperatures;
• the ability to access the section of the pipeline where it is planned to install crimp connection elements - you must remember that this type of product can only be installed on communications with the possibility of further maintenance;
• the configuration of the pipeline section on which it is planned to install the fitting in question, which will allow you to select a product of a suitable shape: cross, corner element, etc.

Advantages

Positive qualities of this type of product:

• the ability to create a hermetically sealed connection;
• ease of installation;
• there is no need to use special tools and equipment, as, for example, when installing flanged or welding analogues;
• experience in performing similar work is not required;
• possibility of installation in areas characterized by complex configuration;
• several types of elements: single-sided, double-sided, etc.

Flaws

The crimp coupling does not last long. This type of product deforms relatively quickly, which is due to constant pressure on an insufficiently strong connection. As a result, the sealing ring begins to leak liquid and a leak forms. If the water supply system is characterized by frequent water hammer or vibration, the fitting will fail even faster than when used under more gentle conditions.

Another significant drawback is the low heat resistance when it comes to products with a polymer O-ring. In this case, the material loses its properties faster, because it is constantly exposed to temperature changes.

Do-it-yourself installation of metal-plastic pipes using press fittings

Connecting pipes using press fittings has a number of advantages:

• unlike screw press fittings, they form permanent connections that do not require monitoring or tightening;
• connections are strong and durable, service life can reach 50 years,
• permissible operating pressure at the joining points – 10 atm;
• They can be installed indoors or filled with concrete.

If you have decided to use metal-plastic pipes, do-it-yourself installation can be done simply and quickly if you use press fittings, since in this case welding, soldering and threading are not required.

The first step in installing a pipeline with press fittings is to cut the pipe at a right angle. The edge is processed by chamfering, the diameter of the pipe is adjusted to the desired size. A stainless steel sleeve is placed on the end of the pipe.

The shaped part of the fitting is installed into the pipe until it stops. A manual or hydraulic press clamp is applied to the sleeve. The handles of the tool are pressed all the way.

Types of couplings

There are different parts depending on the composition of the material: cast iron, steel, metal-plastic, copper. Each type is designed for a corresponding type of pipe.

There are crimp and press couplings.

1. Crimping ones are equipped with rings - one or two. The principle of their operation is the use of polymer seals. Due to external pressure, the material is able to shrink and tightly surround the outer side of the inserted conductor. As a result, the connection is sealed.
2. Press elements create permanent connections. They cannot be reused. If a leak occurs, you will have to replace the part with a new one. This is considered a disadvantage of such connectors.

What does the coupling look like?

Crimp couplings do not have this drawback. They are wear-resistant and durable. But they also have their drawback: low reliability during operation. To reduce the likelihood of depressurization of joints, the fastening of parts should be periodically tightened.

There are also these types of couplings:

• straight;
• plugs;
• corner;
• tees;
• crosses;
• valves.

Valve

Basic rules for installing metal-plastic pipes

Metal-plastic pipes are highly sensitive to mechanical damage, temperature influences, and do not tolerate direct exposure to ultraviolet rays. Therefore, open laying of metal-polymer pipes is possible only in those places where the presence of these factors is excluded.

In order to easily repair concealed metal-plastic pipes with screw fittings, it is necessary to provide inspection hatches at the joints. These elements should not have sharp edges.

Metal-plastic pipes are laid through building structures using sleeves. There should be a gap of 3-5 mm between the inner surface of the sleeve and the outer side of the pipe, which is created using a soft, non-flammable material that allows longitudinal movement of the pipe.

At all stages of pipe laying, it is necessary to remember that the formation of cracks, cuts and scratches on the surface is unacceptable.

Therefore, sharp objects should not be used when unpacking pipes. Marks can only be drawn with a marker or pencil.

For the installation of press fittings, reliable equipment is used, which eliminates the creation of poor-quality connections.

Installation of metal-plastic pipes - video materials will help you cope with this process - should be carried out using hangers and supports offered by pipe manufacturers. When using metal fasteners, the pipe is protected with gaskets made of soft materials.

To solve the question of how to repair a metal-plastic pipe, you can choose one of the options:

• to eliminate a leak, it is necessary to cut out a piece of pipe and install a new one using a connecting fitting;
• if the leakage area is small, you can install only a connecting fitting without buying a new pipe;
• The leak can be sealed by installing a flange with a gasket or sealed with epoxy glue or sealant.

Metal-plastic pipes are the most versatile among polymer pipes; they are reliable in operation, easy to install and have an aesthetically attractive appearance. It is these properties that explain the growth of their popularity.

Source: canalizator-pro.ru

Features of crimp couplings

Crimp couplings are used primarily to connect pipeline elements with the same diameter. Even if it is mounted by welding, the presence of such parts at the ends is mandatory: without them it will simply be impossible to connect to other existing branches of the system. But it is especially advisable to use crimp couplings for steel pipes in industry. After all, they are capable of operating in a very wide temperature range: -50 ≤ T ≤ +250˚C.

An important factor is the fastening of the steel pipeline, some elements of which are connected using crimp couplings. After all, due to the weight during operation, it can bend, which will lead to leaks. Therefore, let us dwell on this issue in a little more detail.

Improper fastening of the steel pipeline will cause leakage at the joint between the pipes and the coupling.

General provisions

So, you thought about it and decided to install the pipeline yourself. And rightly so, with attentive and diligent attitude, any business can be resolved. Where to start?

Take a sheet of paper and draw a plan of the premises where we will install the pipeline. It should look like a top view. As a rule, all the pipes in the apartment/house are replaced at once, and this is, first of all, the kitchen, bathroom and toilet. Carefully measure future pipe passage locations.

Tip: Ideally, draw straight lines with a pencil directly on the walls where the pipe will go and measure them with a tape measure.

Installing a water supply system from metal-plastic pipes is probably the most affordable way to replace pipes without proper qualifications. Feel free to get to work.

Do not forget that there is a double pipe: cold and hot, but there are a number of places where only the cold pipe passes. This is the wiring near the toilet, the supply to the washing machine, dishwasher, etc.

At this stage you already know how much pipe you need. Now carefully consider how many connections of pipes, tees, mixers and other installation units you plan to make.

Some fitting options for a metal-plastic pipe

Advice: it is very advisable that at the stage of compiling a list of components, one of the experienced people will help you. The choice of the type of fitting in a particular location is important and is selected optimally.

Do-it-yourself pipe installation also implies the presence of a certain set of tools.

Let's make a list of what you need:

1. Scissors for cutting pipes. This is a necessary device, don’t skimp, be sure to buy it, otherwise you risk ruining the pipe. Cutting with other tools can cause burrs, irregularities, and damage to the protective layer of the pipe, which will subsequently lead to leaks.

Pipe cutting shears

1. Calibrator. It is also necessary because after cutting the pipe is concave a little inward, but on the contrary, you need to flare it a little so as not to damage the rubber seals.

Pipe calibrator

1. Adjustable wrench, open-end wrenches of the required sizes, pliers, drill.

Tip: you can purchase the necessary tool for installing metal-plastic pipes along with the pipe and fitting, and you will even receive a rightful discount.

So, everything is ready to go. Now it is necessary to dismantle the old pipe, and with it the old valves at the entrance to the home.

If you live in a private house, then you simply shut off the central water supply to the house, and if you live in an apartment, then you will have to call a plumber to shut off the hot and cold water supply in your driveway riser.

Advice: it would be logical to entrust the work of replacing the valves at the entrance to the apartment to a local plumber, who will shut off the water. Otherwise, nothing will happen to him, and you will wait for him for a long time.

It is worth noting separately that the valves at the entrance to the home should only be of high quality. Choose taps that can withstand a pressure of 60 atmospheres and a temperature of 150 degrees.

Do not skimp on such valves, because in the event of an accident they are the only gate into the house.

Review of popular manufacturers

A wide range of high-quality products are produced by the joint Russian-Italian company Valtec. It will ensure reliable installation of pipelines for heating and water supply to your home. Products are equipped with certificates confirmed by laboratory tests. More than 400 types of different sizes and shapes of fittings for metal-plastic pipes, popular all over the world, are produced at very reasonable prices.

The equipment for plumbing and heating produced by OVENTROP has proven itself, which has successfully occupied a leading position in this market segment for more than 150 years. True German quality, reliability, and a wide range of copper and brass products are known in Europe and enjoy deserved popularity among demanding consumers.

In China, hundreds of large and small companies make similar products and often of very high quality, proving the assertion that Chinese is not always bad. And the prices are minimal.

Expert advice and installation nuances

When choosing this product, you need to carefully examine the labeling, even weigh it on your hand. High-quality brass products should be heavy. Do not skimp on equipment and tools, because poor assembly, damage to the outer layer of plastic pipes, creasing, careless bending, all will ultimately lead to leaks and repairs.

Recently, connections with push fittings for metal-plastic pipes have been in demand. They include a strong body, an inner ring, a seal, and an outer casing. Through the window you can control the reliability of fixation.

No additional tools or special qualifications are required. The connection is reliable, resistant to loads, and can be dismantled if necessary. The cost is reasonable, depending on the manufacturer of fittings for metal-plastic pipes, material, availability of protective coatings, etc.

Another frequently used detachable joining method is the use of collet fittings for metal-plastic pipes. They are made of brass according to GOST and have anti-corrosion properties.

Simplicity, reliability, low price are advantages. But you will have to inspect the condition of the nodes once every six months, and these are already disadvantages.

Installation

Installing metal-plastic pipes with your own hands is quite an entertaining and even creative process. Now that the valves have been changed, turn off the water supply and proceed with installation. Install a coarse filter and a fine filter (optional) behind the valve.

They differ in the size of the filter cell. Many people neglect the fine filter, and in vain. It is this that retains small particles of scale from the pipes, which, when they get into expensive ceramic mixers, can damage the smooth surface of the ceramic plates.

In addition, it is he who stops the “trifles” that accumulate in the filter on the faucet spout and reduces the water pressure.

Next, install the meters, if you use them, and start wiring.

If there are many consumers in the apartment that are connected to water in parallel, then use a collector.

This device is good because it provides all consumers with the same pressure, and a separate tap can be mounted on each branch.

A little lower we can see metal-plastic pipe installation video visually. It is useful to know the internal structure of a metal-plastic pipe.

Structure of a metal-plastic pipe

As you can see, it consists of three layers: polyethylene-aluminum-polyethylene, between which there are connecting adhesive layers. Therefore, cutting and installing metal-plastic sewer pipe connections requires precision and accuracy. From the video below you will see how to work with a pipe.

As you can see, there is nothing complicated. A little practice and everything will work out. Before installing the fitting, do not forget to treat the outside and inside edges of the pipe cut.

Otherwise, the rubber seals may be damaged. And to give the edge of the pipe a perfectly even round shape and prepare it for connection, be sure to use a calibrator.

Important: in the process of tightening the nuts when installing the connection, you can easily “tighten” them. When the connection is already sufficiently reliable, a characteristic cracking sound will appear. This means that further tightening may simply ruin the connection.

The connection is tightened using two wrenches, one holds the fitting, the other tightens the nut.

It is also often necessary to simply bend the pipe, without using a fitting. In this case, a special spring will help you, which will prevent the pipe from simply folding.

Such springs can be either internal or external.

Such bends are used by installers to the maximum because:

1. Saving on fittings.
2. There is no risk of leaks, because no connection.

If you plan to cover the pipe with a box, then use this technique.

Now let's watch a video on how to properly connect metal-plastic pipes and fittings.

It is very convenient to attach the pipe to the wall using special clips.

Fastening the pipe to the wall

Such a clip is attracted to the wall, after which the pipe is simply inserted into it. It's very fast and convenient. Such clips are calibrated to the diameter of the pipe and therefore hold very well.

Crimping connection method

Press fittings for connecting metal-plastic pipes are quite easy to use; their design is shown in the figure.

Valtec press fitting device for metal-plastic pipes

Explanation of symbols in the figure:

a – a fitting, for its manufacture, as a rule, brass alloys are used; b – dielectric plastic rings; c – a sealing gasket made in the form of a ring; d, f – crimp sleeves; e – metal-plastic pipe; g – fitting shank (inserted into the pipe ).

The crimping method has its undeniable advantages, the main of which are:

a high-quality connection is ensured; installation in a “Warm Floor” heating system is allowed, and hidden placement in the walls is also allowed; installation is carried out within a few minutes.

Crimping has its drawbacks, including:

the mandatory presence of a press machine, it can be manual or mechanically driven;

Crimping tool set

the device cannot be reused; after dismantling, they are thrown away along with the piece of pipe.

Before you buy press fittings used to connect metal-plastic pipes, make sure of their quality; Chinese analogues are much cheaper than products produced by such manufacturers as: Henco, Far, Ltm, Pexal, Valsir, Tiemme, but are inferior to them in reliability.

Repair

Metal-plastic fittings of sewer pipes periodically require repair. Even if you did all the operations correctly, after a few years the connections may weaken from the effects of differences in temperature, pressure, or simply time.

Since the pipe itself is monolithic, it means that repairs of metal-plastic pipes are carried out at the points of their connection - fittings.

The very first thing to do is simply tighten the connection. This must be done carefully. If the leak does not stop, then you will have to disassemble the connection.

Possible causes of leakage:

1. The rubber O-rings are damaged. They need to be replaced.
2. The pipe has an uneven cut. Align and calibrate the cut.
3. The brass body of the fitting burst. Replace the entire fitting.

Tip: some craftsmen lubricate the joint with silicone, which provides additional waterproofing.

It is worth saying that metal-plastic pipes are produced not only for hot and cold water supply. There are also pipes for heating and sewerage. These types of metal-plastic pipes differ in that they contain not food-grade polyethylene inside, but technical plastic. Therefore, the cost of such a pipe is much lower.

If you still want to make the pipeline maintenance-free, then you need to use not the compression fitting we discussed in the article, but a press fitting.

This pipeline assembly involves creating permanent pipe connections using special press machines. There is no point in buying this expensive equipment for installing several meters of pipe, so in this case it is better to use the services of professionals. And you can fill the pipe with concrete. In this case, the question “how to repair a metal-plastic pipe” disappears by itself.

Source: kanalizaciyadoma.ru

Installation of metal-plastic pipes

This article will discuss the installation of metal-plastic pipes with your own hands using threaded fittings.

The advantages of joining and connecting pipes using special fittings are that no threading is required, and the process itself takes little time.

However, the specifics of the production of metal-plastic pipes require fairly careful handling of them, as well as strict adherence to all installation technology.

This is important, first of all, because in the vast majority of cases a hidden installation of the pipeline is required, which does not allow the slightest violation of the tightness. There is currently a wide range of fittings (fittings) for metal-plastic pipes on sale.

To view the types of threaded fittings, we offer you a page on our website - fittings for metal-plastic pipes.

When you need to install a fitting, we advise you to pay attention to the quality level of the thread. It should be noted that areas where the thread is broken are allowed only when their total length is no more than 10% of the total length of the thread.

The ends of the fittings must have an even shape and be perpendicular to the axis of the product. The threads should not contain burrs.

All fittings, depending on the method of connecting them to the pipe, are divided into threaded (screw) and pressed.

When using threaded fittings, the connection is achieved due to the pressure created on the open expansion ring when the nut is tightened. To ensure that the fitting body is tightly connected to the tip, a special gasket is provided.

Variety of fittings depending on purpose

In addition to differences in parts based on material, there are different types of fittings for polypropylene pipes based on shape and purpose. Such elements are calculated in advance when a clear pipeline installation scheme is known.

Couplings, connectors and adapters

These elements have a cylindrical shape and are used for joining smooth sections of polypropylene pipe. Installation is carried out using an electric soldering iron or an open-end wrench, which depends on the modification of the fitting.

Fitting with transition to external thread

The element has a plastic solder coupling on one side and an external thread on the other. The latter is possible in all pitch sizes and diameters established by GOST 6357. The fitting is used for connecting polypropylene to metal engineering systems or connecting equipment, plumbing, etc.

There is a hex thread on the plastic to hold the pipe with a second wrench while tightening the counter nut. This will protect it from deformation.

Fitting with transition to internal thread

The fitting is similar to the one described above in application and configuration, only the outlet to the metal has an internal thread. The size of the turns and the pitch are possible in accordance with pipe GOST 6357. Through such a fitting, it is convenient to attach ball valves and other elements to the polypropylene wiring.

Polypropylene fitting - one-piece coupling

The part consists exclusively of polypropylene. The inlet and outlet have the same flow diameter. The cylindrical fitting is designed for joining two PP pipes by welding with a soldering iron.

Internal-external transition coupling

The PP fitting has a cylindrical shape with different end diameters. It is used in situations where it is necessary to expand or, conversely, narrow the subsequent part of the pipe. Can serve as an adapter for connecting to a tee or angle. Attached by socket welding.

The element can be of standard length or shortened. The latter option is relevant for limited areas, for example, if the pipe runs close to the radiator connection hole.

Turnkey conversion to internal thread

Cylindrical part made of polypropylene with embedded metal insert. It has an internal thread with dimensions in accordance with GOST 6357. For screwing, iron edges are provided for an open-end wrench.

This allows you to not only hold the fitting, but also tighten it with high force. Suitable for joining polypropylene to steel utilities.

Turnkey transition to external thread

A fitting with a solder coupling on one side and an external metal thread on the other. Contains iron edges for gripping with an open-end wrench. Suitable for connecting ball valves, equipment, and connecting to engineering systems. The thread diameter and pitch are selected depending on subsequent communications.

With union nut

Consists of a polypropylene coupling for soldering and a pressed-in stainless steel part with a union nut and internal thread. Additionally, there is a section on the plastic for a hex key to hold the fitting during the last turns of the key, preventing the pipe itself from turning.

The rubber seal is responsible for the tightness, so winding is not required. Used for transition from boiler, pump or metal pipe fitting.

With union nut for transition to Eurocone

The fitting consists of a socket welding coupling and a steel insert with a VT.708.E union nut and internal thread. Inside there is a metal nozzle with rubber seals. The element is used for fixing polypropylene pipes to shut-off valves or transition to metal-plastic pipes.

Installation is carried out with an open-end wrench, and additional edges on the plastic allow you to fix the fitting, protecting it from turning.

With union nut for transition to “cone”

A connector with a union nut allows you to directly, without any adapters, connect a polypropylene pipe to fittings with “cone” standard outlets.

Manifold fitting with conversion to PEX

Used to connect cross-linked polyethylene (PEX) pipes to a polypropylene manifold.

Detachable coupling for soldering

The fitting is used on a section of a polypropylene pipe where it is necessary to create a detachable connection. It can be used for channel cleaning and other technical needs. The element consists of two mating parts - an external thread and a union nut.

The device is combined - partly from PP and partly from nickel-plated brass. A sealing insert made of synthetically produced rubber is used inside. The sides are joined using socket welding and then twisted together.

Detachable coupling with transition to internal thread

Another type of detachable threaded fitting, but here one end is soldered and the other is screwed. For this purpose, the metal has an additional internal thread. Suitable for connecting shut-off valves and equipment to a system made of PP pipes, as well as joining with communications made of other materials.

Fittings

These are elements for a mating nut or thread for connecting PP pipes with systems made of other materials, such as flexible hoses. Often used on straight sections. Here are some forms of fittings.

Union nut fitting

It has a metal fitting on a fragment of a polypropylene pipe. There is a plastic flange at the end for support. The thread rotates and attracts the plastic to the mating union nut. To prevent leaks, a rubber flat ring is used inside.

The hexagon on the metal part helps to secure the fitting well to withstand pressures up to 20 bar. Often used to connect a reinforced faucet hose.

Union fitting

A polypropylene pipe with a flange at the end, on top of which there is a union nut. The principle of the fitting is similar to the American one, but the metal here is not pressed in, but simply put on top.

The part is designed for screwing onto metal external threads. The rubber seal rests against the flange and ensures tightness.

Corners, elbows, bends, water sockets

A group of polypropylene devices for joining straight sections of pipe, changing its direction, connecting other equipment, and dividing the system. Parts can be made entirely of plastic or with metal inserts.

Square 90º

A fitting with the same inlet and outlet diameters to change the direction of the pipe by 90 degrees. The connection is made with a soldering iron.

Elbow with transition to internal thread

A part with a 90º bend that changes the direction of the PP pipe. The fitting has the same internal diameter, only one side is mounted into the system by soldering, and the other by a threaded connection.

To do this, a metal internal thread is soldered into the second end. The plastic casing around it has a hexagonal design for holding with a wrench.

Elbow with transition to external thread

Angle fitting with a 90º bend for connecting pipes at an angle. One part is soldered using socket welding, and the second is screwed. The metal threads are pressed and have plastic edges for holding with an open-end wrench.

Water inlet with internal thread

Polypropylene corner fitting with mounting plate. With its help, the part is screwed to the wall. The connection from below is carried out using soldering. A ball valve or mixer, as well as a flexible hose, can be attached to the side through the internal thread.

Water inlet with external thread

Polypropylene fitting with 90 degree bend and perpendicular mounting plate. Attached to a vertical base. One edge is soldered into the system, and the second is screwed using an external thread.

Angle with union nut

A variation of the American one, but the polypropylene pipe fragment is made at an angle of 90º. The element is designed for tying polypropylene pipes to metal pipes with external threads. To connect using a union nut, you will need a wrench.

Angle at 45º

The outlet is made of polypropylene with equal diameters at the inlet and outlet. Changes the direction of the pipe by 45 degrees. Fixed on the pipeline by welding plastic with a soldering iron. With its help, it is convenient to carefully bypass architectural structures or equipment located on the path, as well as bring the pipe to the connection point using a shorter route.

Plank with water sockets

Two water sockets with internal metal threads, connected to each other by a rigid polypropylene strip. It has two holes for fixing the device to a vertical surface. Due to the strip, a fixed distance of 150 mm is maintained between the centers of the fitting, intended for connecting a standard mixer.

Contours

The parts are used when two pipes intersect and it is necessary for one of the pipes to pass over the other. You can “jump” over the interfering pipe by using 45 or 90º bends, but more couplings and soldering will be required, which slows down the process. Therefore, it is better to use contours.

Long circuit with couplings

The long contour has a smooth deviation from the axis with a gradual rise and fall. At the ends there are already two couplings for joining with a straight pipe. The fitting allows you to bypass an obstacle in the way such as a riser, window sill protrusion, etc.

Short circuit with couplings

Polypropylene pipe with a short arched bend. Helps you get around a perpendicularly located pipe or other obstacle. The short length is convenient for installation in limited space. Installation is carried out with a soldering iron, and two couplings are already available at the ends, which makes the work easier.

Smooth outline

A section of pipe without couplings that is bent at the factory for installation in obstructed areas. Has a neat bend without loss of throughput. For installation you will need a soldering iron and two couplings, since the part does not have them.

Crosspieces

A type of fitting for attaching four pipes at once. Installation is carried out using socket welding. The element differs in form.

Regular cross

It has four identical outlet pipes located in the same plane with a step of 90º (directed in four directions). Branches the stream into 4 parts.

Coplanar spider

Performs the same role as the outlet, but looks more aesthetically pleasing due to the monolithic body. Inside, the intersecting channels do not mix, but pass over each other. The fitting does not reduce the throughput, since it has protruding walls that increase the diameter of the channel inside.

Two-plane cross

It also has four pipes, three of which are located in one plane, and one in another. The exits are mutually perpendicular. Used to divert polypropylene pipe to the side.

Tees

The device is used to branch a pipe from the main line. It can only be made of polypropylene or combined with metal. Designed for horizontal wiring from vertical risers, for example when connecting radiators.

Tee with transition to internal thread

The main pipe has a flat part, and the side inlet is equipped with a metal internal thread. The outside of the branch is equipped with edges for fixing with a key. The fitting is optimal when you need to add a part with a threaded connection to the system.

Tee with transition to external thread

A plastic element with three outlets, where the side one is equipped with a pressed-in steel part with an external thread. The fitting is soldered in a straight section, and the branch continues with a threaded connection.

Triple adapter

All pipes of the part are plastic, but one has a larger diameter than the other two. Used to narrow or expand the system capacity and branch it.

Two-plane tee

Element for directing communications in two planes. Often used in corners where you need to simultaneously extend the horizontal line with a turn and make an exit to the radiator.

Collectors

Fitting with a number of bends from 2 to 6 or more. It is used to supply liquid and maintain the same pressure in different circuits or uniform distribution of coolant.

Manifold tee

A polypropylene part with a coupling and a small flat area for welding. The upper pipe is equipped with an external metal thread without a hexagonal shell. If an element is welded in series with similar ones, then a manifold of any length can be created, depending on the needs and availability of free space. This type of fitting is relevant for organizing a water heated floor.

Manifold tee with ball valve

An element similar to the one described above, only a ball valve is provided in front of the external thread. Sequential soldering of such parts makes it possible to create a manifold of the required length. If necessary, part of the heated floor can be turned off to reduce the volume of heated coolant.

Polypropylene manifold with taps

It is made in a single body made of polypropylene and, in addition to the main line, has three outlets. Each channel is equipped with its own tap. The subsequent system is mounted by soldering. For reliable fixation of the fitting, mounting eyes are provided. The part is used for distribution of water supply or heating systems.

Plugs, stoppers, caps

The parts are used when testing part of the system when not all taps, radiators or mixers are yet connected. Such fittings may also be required at the end of the pipeline. This is relevant if you plan to continue the system in the future.

End cap

Blind end fitting. Molded entirely from polypropylene. Attached by heating and soldering. To remove it you will need to cut off the pipe.

Polypropylene plug

A plastic fitting with a thread, a stop flange and a hexagonal head for a socket or open-end wrench. The plug is installed in couplings with internal threads and tightened. A rubber gasket is used for tightness.

Filters

A branch on a flat section of pipe where there is an internal metal thread. A mesh cylinder is inserted into it, blocking the passage channel. From the outside, the hole is closed with a bolt with a copper or rubber washer. The filter collects rust, plaque and dirt, which protects the subsequent system from clogging.

Check valves

The fitting is in a plastic case and contains a valve inside that prevents the reverse flow of liquid. Used in private home water supply systems.

It is installed after the pump and prevents water from flowing back into the well if the pump stops. It is also relevant for the supply in front of the boiler, so that the heated volume does not escape through the riser to the neighbors. The screw plug allows you to service (clean) the mechanism.

Compensators

Sections of pipe with a loop that are installed on long pipelines in a vertical or horizontal position. Compensates for linear expansion and contraction during heating and cooling. Help maintain the integrity of the system and extend the life of communications.

Fastenings

They come in the form of clamps, crimping semicircular grips, brackets, and clips. Used for fixing polypropylene pipes and fittings to the wall and floor. Prevents deformation and vibration of the system and promotes a neat appearance.

Ball Valves

The outer casing is made entirely of polypropylene. There is a lever on top that controls the internal flap that closes the passage channel. With its help, you can regulate the flow rate of the coolant or temporarily cut off part of the heating and water supply system circuit (annex, garage, room).

The fitting is mounted using soldering, where the pipes are inserted inside it. Some space is required to turn the lever, so there should be some free space on one side of the element.

Valves

Designed to adjust the throughput of a node or block a channel. A crane axle box or a ground axle box is used inside. The difference from a ball valve is the mechanism that closes the channel.

Installation of metal-plastic pipes. Fitting fastening

It is necessary to cut a piece of pipe to the required length. We do this using special scissors.

IMPORTANT! If you use any other tools, there is a high probability of damaging the protective layer of the pipe, and the cut will most likely turn out uneven. In the future, this will lead to problems related to the reliability of connections - leaks may occur in these places!

In order to perform a high-quality and reliable seal, O-rings are used on the fitting fitting.

To avoid damaging these rings during installation, the pipe should be flared with a calibrator! To connect a metal-plastic pipe with a fitting, nuts and a clamp clamp are used.

First, we put a nut and a clamp on the pipe.

It must be taken into account that before installing a metal-plastic pipe, it is necessary to remove sharp edges inside the pipe along the edges. This can be done using a special device or using improvised tools.

Sharp edges are removed so that during installation of the pipe on the fitting, the inner edges of the pipes do not damage the rubber seals, because otherwise, insufficient tightness of the connection may occur and, as a result, leakage.

The inner sharp edge of the pipes can be removed using a sharpened drill (designed for working with metal) of small diameter. This operation can also be performed using a round file.

Sometimes cutting pipes leads to their partial deformation. To give the pipe a perfectly round shape, you can use a special tool - a calibrator.

Using a calibrator, we flare the end of the pipe and put it on the fitting.

Carrying out tight alignment with respect to the fitting fitting, we return the clamping clamp.

We return the fitting nut and begin to tighten it.

It is important!

When tightening the nut, be careful not to apply too much force. It is necessary to tighten until a certain crackling appears. If a cracking sound appears, it means that the nut has already compressed the clamp tightly enough around the metal-plastic pipe.

In the case when you need to bend a metal-plastic pipe with your own hands at a right angle, it is advisable to use a special spring - it will not allow the pipe to be pinched at the bend! You can find out more on the page of our website - bending of metal-plastic pipes.

To install metal-plastic pipes to the surface, as an option, you can use special devices - clips.

There are clips in different sizes designed to fit different types of pipe sizes. In order to lay the pipe neatly and evenly over the clips, it is necessary to make markings to secure them.

The clips are fixed using screws, dowels, self-tapping screws and even nails. Since the pipe snaps onto the clips quite easily, you don't have to use much effort.

Source: gvozdem.ru

Installation and replacement rules

There are several basic rules that the installer must follow during the assembly of polyethylene communications:

1. In the area where the elements meet, it is necessary to remove all possible types of contamination.
2. Parts must be dry. Even a few drops will reduce the strength of the weld.
3. It is necessary to strictly observe the fixation time when soldering products to prevent deformation of the connection.
4. The edge of the HDPE pipe must be inserted into the connector deeply enough - up to the internal stop.
5. When laying in the ground, it is desirable to have a reserve length so that during subsidence or soil movement the HDPE pipe is not torn out of the fitting.
6. Do not use excessive force when tightening the union nut of detachable connectors, as this may lead to their deformation or slippage of the O-rings. When reused, the rubber seals are replaced.

Installation technology

The installation procedure for connecting parts depends on the selected type. Thermal polyfusion technology is used to weld sections of rolled pipes and fittings made of polyethylene. This is heating the surfaces to be welded to a certain temperature and quickly connecting them to each other. Soldering is performed according to the following scheme:

1. Cutting pipe products to required sizes.
2. Cleaning the end surfaces and calibrating the holes.
3. Chamfering edges.
4. Degreasing of surfaces in the welding zone.
5. Inserting parts to be heated into the connectors of the welding device.
6. Docking of heated parts.
7. Fix the parts in this position for 20–30 minutes to cool the weld area.

It is even easier to connect parts of the pipeline system using fittings with embedded electric heaters. To do this, you need to perform a number of simple steps:

1. Cut, clean, chamfer the outer edge of the pipes and degrease all parts.
2. Install the electric welding coupling onto the mounting end with clear centering to avoid distortions.
3. Connect the cables of the welding machine to the terminals of the embedded heater.
4. Leave the connected parts in the fixed position until they cool completely.
5. Check the tightness and strength of the joint.
6. To install compression fittings:
7. Cut the pipe to the required size and clean the end of burrs.
8. Align the hole using a calibrator and cut a chamfer from the outside.
9. The HDPE pipe is carefully inserted into the connector body so as not to damage the sealing gasket. Sealing will be easier if you apply silicone sealant to the surfaces to be joined.
10. Tighten the union nut by hand or with a wrench.
11. Repeat the procedure on the other side of the shaped part.

Tools needed to work with metal-plastic pipes

First, you need to understand that a metal-plastic pipe, depending on the type of fittings used, can be assembled either using a special press or using crimp nuts.

If we talk about the reliability of certain fittings, they are approximately at the same level. The difference between them is that, unlike crimped ones, there is no way to fix pressed end switches that have leaked. The leaking fitting only needs to be thrown away and a new one installed in its place.

Connection of metal-plastic pipes - fittings

In addition, to install such a pipe you need an expensive press, which makes no sense to purchase for a one-time job. Therefore, in the master class we will focus on the most common compression fittings, which even a schoolchild can assemble with his own hands.

Where are they used?

The main areas of application for couplings are construction and repair work that involves connecting pipelines with an outer diameter of up to 60 mm. Crimp types of connections are used when installing water supply systems. Both cold and hot. Heating structures, heated floors, when transporting water for industrial needs. For example, for irrigation.

Cast iron connection

The release coupling for cast iron pipes is universal and can be used for steel, asbestos-cement, and PVC conductors. The body of such a part is high-strength, cast iron, coated with epoxy. Has a rubber seal on the inside. Operates at temperatures from -25 to +70 degrees. Used for water supply and sewerage systems.

Release coupling for cast iron pipes

The cast iron connector has the following advantages:

• does not rust;
• is able to connect water pipes from different materials;
• convenient and easy to connect;
• operates under the most unpleasant operating conditions;
• dismantled without problems and at any time;
• The lip seal allows installation without much effort.

Metal-plastic connection

Crimp couplings for metal-plastic pipes have weaker characteristics than metal ones. This is a compression connection piece suitable for plastic conductors.

Metal-plastic connection

The technical specifications are as follows:

1. Easily connects pipeline sections and plugs branches.
2. Easy to install.
3. There is no need to use complex equipment or involve specialists for work.
4. Possibility of connecting polypropylene, plastic and other materials.
5. They can be quickly disassembled and reassembled when reconstruction or maintenance is required.

Couplings for copper pipes

Crimp couplings for copper pipes also have their own varieties and features. There are capillary, compression, threaded options. Such parts are in demand due to their durability, strength and simplicity. The sealing ring ensures the reliability of the water supply system.

Threaded couplings can be disassembled and reassembled if necessary. They have high tightness. Resistant to mechanical and chemical influences. They withstand blows very well. The connection process does not require the involvement of professionals or special tools. Self-assembly of structures is possible.

GEBO couplings

The GEBO crimp coupling for steel pipes deserves special attention. The part has no thread and is connected using a compression method. The GEBO element is connected not only to steel, but also to polyethylene structures.

The part is most often purchased to eliminate emergency situations. Without using welding or tapping, the pipes are connected back together. The GEBO coupling is used for both temporary and permanent steel water supply systems.

The convenience of the part is also that you can work with them using only adjustable wrenches. You don't need to have any special skills. Has the ability to be disassembled.

But, despite all the positive characteristics of the connector, it is still more of a temporary solution to the problem.

Tool for metal-plastic pipes

But let's go back a little and study the tool for metal-plastic pipes. To connect metal-plastic pipes you will need four things - a pair of adjustable wrenches (preferably Swedish), a calibrator, special scissors and a spring of the appropriate diameter for smooth bending of the pipes.

• With the keys, everything is clear without words; their purpose is to tighten the nuts as tightly as possible.
• The calibrator is used to expand the internal diameter of the pipe at its connection with the fitting.
• The purpose of the scissors should also not raise unnecessary questions - they are used to cut pipes.
• Well, the purpose of springs has already been mentioned above.

How to bend a metal-plastic pipe correctly

Armed with this simple and few tools, you can get to work.

Types of Compression Fittings

There are two types of such connections of pipeline elements:

• crimping They are equipped with one or two rings. The operating principle of this type of parts is based on the use of a polymer seal. Under the influence of external pressure, this material is compressed, tightly covering the outer surface of the inserted pipe. The result is a tight connection.
• press With their help, a permanent connection is created. The disadvantage of press fittings is that they cannot be reused if a leak occurs. Then it will simply need to be replaced.

The crimp coupling for steel pipes does not have this disadvantage. Such fittings are made from various materials, but they all have the following advantages:

• wear resistance and durability;
• large selection of different configurations.

The main disadvantage of a crimp coupling for a steel pipe is the relatively low reliability of the connection. In order to reduce the likelihood of depressurization of the joint, the fastening of this part must be tightened periodically.

For steel pipes, you can select a coupling of any configuration and purpose

The main area of ​​application for compression fittings is repair or construction work involving the connection of metal pipes whose outer diameter does not exceed 60 millimeters. The design of this part consists of a body (base) and fittings equipped with ferrules and union nuts, which ensure reliable fastening. Quick assembly/disassembly is the main advantage that characterizes these removable products. After all, if the need arises to dismantle the pipe, you will not have to cut the weld.

Advice! To replace an adapter of this type, you can use not only a similar model, but also another fitting with identical characteristics.

Convenient and inexpensive crimp couplings for connecting steel pipes are practically free of drawbacks, and if leaks occur during operation, this will most likely be caused by poor quality work of the contractor.

Do-it-yourself installation of metal-plastic pipes: where to start

Let's start learning how to work with metal-plastic pipes by learning how to cut them correctly. The fact is that this type of pipe itself is a relatively soft material - incorrect or careless pressure with scissors can simply flatten the end of the pipe. A deformed pipe, even if straightened, crimps much worse, therefore, the likelihood of a leak increases.

Do-it-yourself installation of metal-plastic pipes - trimming

The process of cutting metal-plastic pipes looks something like this: first, with light pressure, you need to make a small cut half the diameter of the pipe, after which, turning the scissors in a circle, we cut the pipe to the end. In this way, a smooth and uncrumpled edge of the pipe is obtained.

Fitting device for metal-plastic pipes

High-quality installation is impossible without the correct connection of the pipe with the fitting. To understand the principle of their connection, it is necessary to study the design of the compression fitting.

It consists of three parts - a body (on one side of which there is either a threaded connection or a fitting, and on the other there is a fitting with rubber ring seals), a ferrule nut and a cone ring.

It is these three elements that ensure the tightness of the connection. This connector works quite simply - as the nut is tightened, the ferrule compresses the pipe, forcing it to tightly and forcefully fit the fitting with the rubber seal.

Types and technical features of crimp couplings for pipes

A crimp coupling is a fitting that is intended for assembling pipes without sockets. In cases where welding is not possible or is excluded, this option is used. Also, these elements are used when pipeline systems require frequent assembly (disassembly) during their operation.

Crimp coupling

Steel pipe crimp couplings are often used to seal a steel structure.

How to connect metal-plastic pipes

Now about the direct connection of the pipe and fitting. To begin with, you need to put a nut on the end of the pipe to be connected and then tighten the brass ferrule ring.

In different models of metal-plastic pipes, the crimp ring can be made in different ways - some manufacturers make it a cone, while others make it straight with large chamfers. Those with chamfers can be installed on either side, and those made with a cone are put on the pipe with the thin side away from the fitting.

Have you put it on? Now, the evenly cut edge needs to be calibrated. As a rule, the internal diameter of metal-plastic pipes is slightly smaller than the fitting fitting - this is done in order to achieve a high crimp density.

In normal conditions, it is quite difficult to pull the pipe onto the fitting. We insert the gauge into the inner hole of the pipe and, turning it in different directions, immerse it a couple of centimeters deep.

Some craftsmen use the handle of an adjustable wrench instead of a calibrator - this is incorrect and can lead to unpleasant consequences in the form of deformation of the end of the pipe and, as a result, leakage of the connection.

Working with metal-plastic pipes - calibration

Lightly moisten the fitting fitting with water and place the pipe on it. You need to pull it until the very end, until the pipe rests against a small white ring. If you do not insert the pipe all the way, the chances that it will be torn off during operation increase several times. At this stage, you should check the evenness of the cut - if the pipe rests against the white ring evenly on all sides, then everything is in order.

If there is a gap of more than a millimeter on either side, then it is better to remove the pipe and cut its end again, since such a connection can lead to a leak.

Connection of metal-plastic pipe and fitting

If everything is connected normally, then you can move the nut as close to the fitting as possible and, using adjustable wrenches, tighten it with all the force until a characteristic creak or squeak appears.

Don’t be afraid to pull - if the fitting is of high quality, the nut will withstand any load. If it bursts, that's even better. You will get rid of low-quality spare parts, the operation of which could lead to a flood.

Polyethylene PE-X

PE-X differs from ordinary polyethylene in the cross-linking of the molecular structure of the polymer: long molecules, when chemically treated or bombarded with electron beams, form cross-links in addition to longitudinal ones.

As a result, the physical characteristics of the plastic change; Moreover, it acquires shape memory. If you stretch a cross-linked polyethylene pipe, after a short time it will return to its original size.

Cross-linked polyethylene PEX

Characteristics

• Operating temperature: 90 degrees (short-term heating up to 100°C is acceptable);
• Working pressure: up to 20 kgf/cm2;
• Service life: at least 50 years.

Please note: with increasing operating temperature, the maximum permissible operating pressure and service life of all plastic pipes without exception decrease. For example, at +95°C the maximum operating pressure of a pipe capable of withstanding 20 atmospheres at room temperature will drop to 10-12 kgf/cm2. At 95°C and 8 kgf/cm2, PE-X water supply will last no more than 8 years.

Fitting

Two types of fittings are used with PE-X: