How to solder a HDPE pipe with polypropylene. Methods for connecting HDPE pipes and the necessary fittings for this. Cold mounting

Currently, more expensive and heavy pipes made of metals and alloys are being replaced by products made of various kinds polymers - polypropylene, polyethylene, etc. Such pipes, although they cannot completely replace metal ones, are actively used in almost all areas of industry and in urban communications. Polyethylene products are especially popular low pressure(PND); below we will talk about its application and how to connect HDPE pipes to each other and to products made from other materials.

Areas of application for low-density polyethylene pipes

Due to the lightness, strength and variety of ways to connect HDPE pipes, they are used in many areas, for example:

arrangement of water supply systems;
installation of sewer circuits;
as protective boxes power cables and wires when creating electrical networks;
as water-repellent shells when laying heating mains;
to prevent damage to cables of communication systems;
when digging artesian wells;
as molds for casting;
for supplying water to vegetable gardens, greenhouses, etc.

Methods for connecting HDPE pipes

If possible, both connect HDPE pipes and disconnect them back, fastening methods are divided into:

detachable- additional parts (reinforcement) are used to fix the elements; the design can be repeatedly assembled and disassembled, replace individual components;
one-piece- welding, gluing, etc. are used to fasten the elements; it is impossible to disassemble the finished circuit without damaging the components.

Advantages of the first method:

economy- Detachable connection allows you not to buy unnecessary parts, if necessary, replace only one; in addition, there is no need to purchase specific devices for welding or soldering pipes;
ease of operation- connecting HDPE pipes with fittings is quite easy to implement and does not require excessive physical effort; in addition, it is possible in conditions that do not allow the use of welding machines, for example, in the liquid column;
rapidity– with the necessary skill and quality of consumables and fittings, the work can be completed in a short time

Making a detachable pipe connection

This type of fastening of parts can be done in two ways:

in the bell. In this case, the narrower end of one pipe is inserted into the expansion - the socket - of the other and sealed with special materials. In most cases, it is used in the design of non-pressure (gravity) sewerage.
Fitting and flange connection of HDPE pipes - as the name implies, to ensure this method of fixation, special devices: flanges, couplings for HDPE pipes and others.

Couplings for plastic pipes

Like the products themselves, the couplings for HDPE pipes are made of polyethylene. When producing products, an extrusion technique is used.

Advantages of using couplings:

durability - the product can serve for decades;
reliability of pipe fixation and tightness;
resistance to temperature changes and external mechanical loads;
chemical neutrality;
versatility of use;
the ability to both connect a HDPE pipe with polypropylene, and fasten pipes from one type of plastic.

Types of couplings:

Compression. Both external and internal threads are applied to it. The fitting is usually used in the arrangement of heating and gas supply circuits. It is this type of coupling that solves the question of how to connect a HDPE pipe to a metal one: for this, a metal thread is applied at one end of the product. See also: "".
Simple coupling . It is used to connect homogeneous plastic products with the same cross section.
reduction. It is used in cases where pipes need to be fastened different diameters. As you might guess, the input diameters of such a coupling are also different.

Compression connectors

How to work with compression fittings:

The product is disassembled by loosening the union nut.
The surface of the pipe section is cleaned of dust, dirt, grease, etc.
At the end of the pipes, chamfers are made using special device– a beveler – or a simple sharp knife. The second method is less accurate and poses a certain danger to the health of the worker.
On the surface of the pipe, mark with a marker how far it will go inside the fitting.
Before entering, the end of the pipe is treated with liquid soap for better sliding.
The pipe (with force) is inserted into the fitting, carefully, avoiding damage, overcoming the resistance of the rubber seal.
Check the accuracy of the connection and tighten the union nut without applying excessive force to avoid damage to the fitting. See also: "".

Permanent connection of polymer pipes

Types of pipe welding:

butt;
using electrical couplings.

The first method requires welding machine for pipes, heating their ends to the melting temperature. After that, the ends of the products are pressed against each other until cooling and the formation of a homogeneous mass.

pipes must be round, without deformation;
the seam must pass through the entire thickness of the wall of the product;
elements must not be displaced by more than 1/10 of the wall thickness;
the height of the welding bead for products with a wall thickness of not more than 5 mm - 2.5 mm or less, for thick-walled pipes (6-20 mm) - more than 5 mm.

When welding with an electric coupling, special polyethylene couplings with built-in electric spirals are put on the ends of the pipes. After voltage is applied, the ends of the pipes are heated, melted and welded to the coupling. Before carrying out the operation, the surface of the pipes must be cleaned, and during heating and cooling, the products must not be displaced relative to their original position.

The connection of HDPE pipes has many variations, it is quite simple in execution and, with the proper quality of work, is durable and reliable.

Modern methods make it possible with the help of PP elements to pull durable and reliable network engineering that are not subject to corrosion. In this case, it is important to know how to connect polypropylene pipes.

They can be installed using threaded or welded fittings.

Pairing Methods

High-quality pairing of PP pipes is impossible without taking into account their wall thickness.

The following are thin-walled products that are connected by threaded fittings.

Pipes brand PN-10 for cold water supply ( working temperature+20°) or underfloor heating systems (up to +45°).
PN-16 analogues used for cold water supply at increased pressure or in heating systems at low pressure.

Welding is the best option in the following cases.

If they mate with their hands universal pipes brand PN-20. These products are able to withstand the temperature of the working environment of +80°.
When reinforced aluminum foil pipes PN-25. This product designed for hot water and heating systems. It withstands the temperature of water or coolant at + 95 °.

Note! Polypropylene pipes are easy to connect, which is why they are so popular. You can connect them without even having special plumbing training.

Docking without thread

You can connect plastic pipes without soldering using press fittings, crimp analogues or the latest Belgian push fittings, which are fixed themselves.

Crimping elements require only two wrenches. Before connecting a HDPE pipe to a polypropylene one, it should be noted that press fittings are more reliable. They create a guaranteed tight connection. However, to work with them, you need a special tool.
Push fittings only require a calibrator and a cutter. They are made from PVDF, an environmentally friendly and durable material. To seal the elements, EPDM rings are used, which are the most reliable. The price of such fittings is quite high, but they are worth it.

Threaded connections

First, how to connect polypropylene pipes using detachable elements.

It is impossible to cut threads on PP pipes on your own. Therefore, for docking, you will need threaded fittings. To ensure the tightness of the joints, plumbing Teflon tape (fum-tape) and seals will also be needed.

Types of threaded fittings

Couplings with the same thread on both ends.
Elbows 90° and 45° with union nut.
Triple elbows and tees for connecting pipes of the same diameter. They can be male or female threaded.
Crosses.
Plugs.
Saddles for network branching.
Combined couplings with external and internal thread, as well as union nuts.
Adapters with external thread type DG.
Combined 90° elbows with external and external thread, as well as a union nut.
Combined tees having the same structure.
Squares for fixing plumbing fixtures.
Passage water outlets.
Ball valves, angular (with "American") or straight.

The instruction says that it is very simple to join pipes using these elements. It is only necessary to pre-wind the fum tape, and then screw the fitting onto the pipe.

Docking of elements from different materials

A little about how to connect metal pipe with polypropylene.

This requires special adapter fittings. One end of them is designed for soldering with plastic element, and the other has a thread for connection with a metal counterpart.
A collapsible type of connection is also used. This is the so-called "American" - a fitting with a metal insert and a union nut or a PP fitting and a union nut.

Note! The best option- use nickel-plated elements for transitional mates with metal pipes brass inserts. Fittings should be screwed with a tightening wrench. On the sanitary appliances transitions with plastic threads cannot be used.

Welded method

Welded joints are one-piece. During the fusion of the sides of the two elements, their macromolecules mutually penetrate into the parts and combine with them. That is, the process of diffusion takes place.

Therefore, such welding is called diffusion.

For products with a cross section of less than 63 mm, a socket type of welding is used.
For analogues with a diameter greater than 63 mm, a butt welding type is used.

Socket welding process

Before connecting polyethylene pipes or analogues from PP, you need to prepare tools and materials.

Soldering iron (iron) for plastic products, a hacksaw for metal or a special cutter, tape measure and marker. If the elements are reinforced, then a shaver will be needed - a device for stripping aluminum foil.
Of course, the pipes themselves will be needed and, as necessary - different types fittings.

The welding machine includes a heating element and a set of nozzles for pipes different sections- from 16 millimeters to 63. When the soldering iron turns on, the indicator starts to work. As soon as it changes color from green to red, the nozzle has heated up to the required temperature of +260 degrees. This happens in 10/15 minutes.

Note! All work is best done indoors. In any case, when negative temperature ambient air, the pipeline must not be welded.

Briefly, the process looks like this.

Mark the pipes. Don't forget about the socket depth and add 2mm to it.
Cut the desired pieces of pipe. Do it strictly at a right angle.
Install the sides of the elements to be joined on the heated nozzle of the welding machine.

Wait for the time required to heat the pipe and fitting.
Take out the items.
Connect the parts and firmly press them together.

Connection of pipes of large diameters

Butt welding is used to connect plastic pipes with a large diameter and wall thickness (from 4 mm or more):.

For this method of welding, fittings are not needed in most cases.

First, the sides to be welded are trimmed until they are completely parallel.
Pipes are inserted into the welding machine.
Then they are connected, while the accuracy of work is regulated by a centering device.
In the course of work, do not forget to ventilate the room, as the plastic smokes, emits carbon dioxide and water vapor.

Below is a table of welding characteristics.

Conclusion

Having figured out how to properly join PP pipes, you can very quickly assemble high-quality plumbing at home.

The video in this article will tell you more about its topic.

Any building material has its own operational period. When it ends, it is necessary to replace the spent product. This also applies to pipes. Today, polypropylene products are so easy to install that they make it possible to completely replace the heating / plumbing complex without much difficulty. You just need to know how to connect polypropylene pipes.

Such a material is good in that the products have the following properties:

Durable. They can cope with pressure drops and high temperature exposure without changing their own indicators;
durable;
Resistant to corrosion;
Easily installed. For installation, you only need to heat them up with a special device, connect them using fittings. In order to connect a metal pipe with a polypropylene one, fittings are also used.

Types of polypropylene products

There are four types of polypropylene products:

PN 25. The maximum allowable pressure is 2.5 MPa. It is applied in systems of heating, hot water supply systems;
PN 20. A universal product that can handle loads up to 2 MPa. It is used in cold / hot water supply systems (if the water temperature is not more than eighty degrees Celsius). It is high-strength because there is foil reinforcement inside;
PN 16. Designed for heating systems with low pressure and cold water pipes;
PN 10. A product with thin walls that can withstand loads up to 1 MPa. It is often used in the arrangement of a warm floor (temperature not higher than forty-five degrees), cold water supply (up to plus twenty).

To find the right product for your needs, consult with a specialist.. You can also watch a video that explains which pipes to use in different situations.

Tools

Ease of installation - key value polypropylene. You will need certain materials, special tools:

polypropylene pipes;
pencil;
clips to fix the highway;
roulette;
couplings for connection;
corners;
eared-mrv. It is used to fix the mixer;
MRV outlets with metal thread;
soldering device;
scissors for plastic items.

Connecting polypropylene pipes to each other

Diffusion welding

Now the question of how to connect polypropylene pipes is a popular one. The most common method is diffusion welding. In order to securely fix them, fittings are used: couplings, corners, adapters.

Polypropylene pipes during the installation of a cold water supply system will definitely last up to fifty years. Approximately twenty-five years they will last during the installation of hot water supply. Please note that the service life depends on the inlet pressure and temperature.

Polypropylene products are very durable, able to cope with any changes in the system. High pressure and low temperature conditions can in no way affect the duration of their operation. High pressure and temperature, which are fixed at the same time, will reduce the life of the pipes by five to seven years. There are no extreme loads in domestic pipelines that can deform them, so there is no need to worry.

Device "Fuzioterm"

If you are interested in connecting with each other, pay your own attention to this unit. Cold products made of polypropylene are connected, then the joint is processed with the Fusioterm device. If you need to weld 2 ends of the pipes, they are inserted into a special hole in the device, after preheating the device to two hundred and sixty degrees. Then they are pulled out and connected.

Socket soldering

If the radius is less than twenty millimeters, then they can be connected by manual welding. To connect to a metal part, a different method must be used. You will need a special soldering iron for socket soldering.

1. Cut off a piece of the product with special scissors. If reinforcement is present, process it, clean up the reinforcement layer in the cut area.

2. Put on gloves, heat up the soldering iron and start soldering.

3. Do everything quickly so that the joint area does not deform.

Connection of polypropylene pipes with polyethylene

How to connect a polyethylene pipe with polypropylene? For this, butt welding is used. The ends are heated until the material melts. Then they are compressed. A joint is formed, the seam cools down. Heating is carried out by a flat metal tool coated with Teflon.

The main advantage of such welding is that for laying straight sections it is not necessary to spend money on connecting elements. The downside is that, regardless of the radius of the connected products, you will need to follow many butt welding rules. In addition, connecting two segments takes a lot of time. Now you know how to connect a HDPE pipe with polypropylene.

Connection of polypropylene pipes with metal

The question remains how to connect polypropylene pipes (under conditions high pressure) with metal? There are 2 methods. You need to choose one of them, starting from the radius.

1. For products with a radius of up to 20 mm, you need to use threaded connections on the metal part of the system. Fittings, on one side of which there is an ordinary coupling for mounting to plastic, and on the other - desired thread are sold everywhere. In order to seal steel thread, use linen with drying oil or modern sealing materials. This will ensure the durability of the connection.

2. For larger sizes, it is better to use flange connections. An iron thread with a radius of 300 mm cannot be screwed by hand, even if you are a strong man. So how then to combine a metal pipe and a polypropylene one if they large diameter? Use special adapters that can be purchased at the store.

Thread and flanges allow you to connect metal and polypropylene pipes without soldering, which is very convenient.

Connection of polypropylene pipes with metal-plastic

How can you connect metal-plastic pipe with a polypropylene product? Compression fittings must be used. They are usually made from a material that is resistant to corrosion (copper, brass). The design includes a fitting, a ring, a union nut. Through their crimp is fixed.

When the nut is tightened, it presses on the ring fixed on the pipe section. Typically, such a connection is used in plumbing and heating systems.

Fitting types

It is possible to connect 2 pieces of unequal materials with special fittings. They are also used when you need to connect plumbing with steel fittings. Inserts on fittings are required for strong connection. They can be made from brass or chrome. Today, the most common options are:

crosses;
combined tees;
coupling;
Ball Valves;
adapters (have an external plastic thread).

The right choice of polypropylene products

It is difficult to choose something specific from the wide range provided by many manufacturers. There are criteria that must be followed when purchasing.

1. Products must be in accordance with the characteristics of the plumbing / heating system.

2. In order to assemble the system with high quality, you need to purchase all the parts from one manufacturer. This approach will create a reliable and durable design.

3. When choosing, pay attention to the quality of pipelines, fittings. Evaluate the following:

smoothness of the inner / outer surface;
the presence of cracks, chips, bubbles, heterogeneous structure, foreign particles;
the correctness of the geometry;
same wall thickness.

4. Remember that polypropylene products are intended for operation at a temperature not less than minus twenty. Ask the store how to store them in the winter. Improper storage leads to deformation of products.

5. If drinking water will flow through the water supply, ask the seller if the product meets the standards of sanitation and hygiene.

6. Buy only straight pipes, no bends. In stores, they are stored vertically, so they gradually bend, cease to be even. Be sure to pay attention to this.

7. Choose products from trusted manufacturers that have proven themselves and have all the necessary certificates. Trying to save money, you can buy a low-quality product that will not be able to serve you for the entire operational period. Therefore, it is better to pay more once than to spend money again and carry out complex repairs to the water supply / heating complex.

8819 0 0

Installation of a polypropylene pipeline is so simple that you can easily carry it out even in between watching your favorite TV shows or series. The main thing is to stick to some general rules and understand the basic principles of connection plastic pipes . I will tell you all this from my own experience.

Installation work

Starting to work with polypropylene pipes, I first of all remembered their main qualities:

The low price allowed me, without much abuse of family budget purchase all necessary plastic products, including connecting fittings, with some margin. After all, even having the appropriate experience, no one is immune from making mistakes, and it is better to have replacement parts at hand in case of an unsuccessful operation, and not run after them to the store, leaving an unfinished pipeline and an unfinished series;

A simple connection instruction including "hot" and "cold" methods. But simplicity does not preclude the need for availability special tool for each of the options. In what follows, I will describe both of them in detail, since different areas I used both soldering and compression fittings. It is better for you to make a choice in advance in order to take care of the availability of appropriate equipment. You can do it right after reading the article;
No corrosive processes. plastic surface is not subject to either internal corrosion, which can be provoked by the transported liquid, or external, which usually occurs after laying the pipeline in the ground. Thus, when laying an underground water supply, I knew that it would last for decades, but only taking into account the quality and absolute connections.

If you plan to use polypropylene pipes for installing a heating system, then I recommend purchasing reinforced samples that can withstand high temperatures, which will eliminate the risk of an emergency.

Based on the foregoing, I purchased materials with a margin, took out the right tools and prepared to make quality connections that can be left unattended for years to come.

hot method

Where I planned to lower the water supply line underground, I had no doubts about the choice of the connection method: only soldering. The melting point of propylene is only 260 degrees Celsius, and after solidification are formed fully sealed seams. In addition, the process itself is quite fast. The impossibility of dismantling me in this case did not bother me at all.

When laying pipelines indoors, welding is also excellent. The only exceptions can be those areas where disassembly of pipes is required, or a situation in which it is not at all possible to get a pipe soldering iron.

If you have a one-time installation planned, then it is not necessary to purchase an expensive welding machine for plastic pipes, it would be more rational to rent it.

Before connecting polypropylene pipes using the “hot” method, in addition to the “iron”, I also prepared the following tools:

Now I will describe to you in detail how polypropylene pipes are connected, you really will have time to install small sections during the period of scrolling commercials on TV:

If this is your first time trying to solder plastic pipes, then I recommend that you first practice on a couple of products that will not be included in the system being installed.
So you "fill your hand" and can avoid typical mistakes when performing "finishing" work.

Training:

I took out a soldering iron from a suitcase where he was, and placed it on a level and stable oak table. You can put the device on the floor or on the asphalt, the main thing is that it has a reliable position, because you have to deal with high temperatures;

Then inserted nozzles corresponding to the diameters of the elements to be soldered. At the same time, a product is installed under the pipe in the form of a kind of “bowl”, which wraps around its edge with outside, and under the tubular element that enters it and performs melting from the inside;

Turned on the device. If your device has a power regulator, then set it to 260-270 degrees Celsius. If this is not the case, then the unit will automatically heat up to the specified temperature;

Markup. Here I have already moved on to work with the pipes themselves. With a tape measure and a pencil marked out the necessary segments for the formation of the pipeline. In addition, measured the depth heating elements and, adding a couple of millimeters, applied it to the soldering points. This can be done after cutting products. This technique will help you control the immersion of the edge of the cut into the nozzle, since excessive melting can lead to the formation of a bulge in the seam that prevents the passage of liquid;

Cutting. The main thing here is to observe a right angle. Thanks to some experience, I have no problems with this, that is, evenly brought the scissors to the line and made a clear cut with one smooth strong movement. Try also, without excitement, with the necessary efforts to complete the cutting. Otherwise, if you make oblique cuts, you will have to level them with a hacksaw or knife. It is also worth noting that when using reinforced pipes, you must first remove the upper layer plastic and foil laid under it;

Heat. At this stage I I put the prepared coupling on the mandrel, and inserted the pipe section with some delay into the nozzle-sleeve. Why belatedly? Because the walls of the connecting element are thicker, and, accordingly, they will melt longer, that is, the head start will not interfere with them. Keep the products in this position should be guided by the following table:

Docking. After the above time has passed, I removed both fragments with melted edges from the welder and connected, again, strictly at a right angle, after which he held the time indicated in the following table:

Cross section, cm	Connection time, s	Cooling time, s
2	4	2
2,5	4	2
3,2	6	4
4	6	4
5	6	4
6,3	8	6
7,5	10	8
9	11	8
11	12	8

In no case do not rotate the connected products at the time of solidification, as this may provoke a violation of the tightness of the seam.

Control. I let water through the finished pipeline and checked all joints for leaks. If you suddenly find one in yourself, then cut out the problem area and weld a new segment in its place.

cold method

Compression fittings allow you to connect polypropylene pipes without soldering. All you need besides the connectors themselves is crimp key, which, as a rule, is sold with them.

The very process of connecting pipes in a “cold” way, I performed as follows, when I didn’t have an “iron” at hand, and it was necessary to restore the damaged section of the water supply urgently:

Measured and cut off the desired pipe fragment;

Calibrated hole. It is very important that its cross section ideally matches the diameter of the fitting tail;

Put on the edge of the pipe ferrule;

Then I inserted the fitting itself inside;

Crimped the clutch special key, securely fixing it on the pipe;

I checked the coupling for the presence of characteristic recesses, indicating a quality connection.

The described method also solves well the problem of how to connect a metal pipe to a polypropylene one. To do this, simply select the appropriate compression fitting, in which one of the ends is equipped with a metal thread the right step and diameter.

If you have a question: "How to connect a HDPE pipe with polypropylene?" Then again, you can turn to compression fittings, since welding here, most likely, will not cope due to the significant difference in the melting temperatures of these materials. At least I wouldn't risk it.

And a bit of "tar in the ointment": despite some versatility of the "cold" connection method, it takes much more time to implement. So, if you have to install a long pipeline, then during the time of advertising on TV you may not have time to cope with the task.

Conclusion

A little practice and following the above recommendations will allow you to lay water supply lines from polypropylene pipes, practically without looking up from watching your favorite TV shows and TV programs. The main thing is to be careful and accurate, since a mistake made will take much more time to correct it than timely control of the work being done.

The video in this article will allow you to familiarize yourself with some of the additional information, which is close in content to the material presented. If you have any additional questions on the topic, ask them in the comments.

July 25, 2016

If you want to express gratitude, add a clarification or objection, ask the author something - add a comment or say thanks!

AT modern construction polyethylene pipes are used very actively. With their help create non-pressure and pressure pipelines are sewers and plumbing systems, irrigation systems and the like. The connection of HDPE pipes with fittings allows you to carry out all the work with minimal labor.

For water and sewer networks, low-pressure polyethylene is used, grades PE-100 and 80.

Polyethylene is characterized by elasticity and strength, as well as ease of installation - all work will be carried out at minimal cost.

Advantages that allow the use of HDPE pipeline in networks various types, are:

long operational period - up to 50 years;
immunity to external aggressive environments;
the possibility of creating a pipeline without digging trenches, which significantly reduces the cost of the system;
lack of tendency to corrosion;
pipes are smooth inside and do not become clogged with deposits during operation - high throughput stored regardless of the period of use;
light weight greatly facilitates installation;
ease of processing and creating connections allow you to create the most complex network configurations;
resistance to temperature fluctuations;
increased plasticity, mechanical strength- such pipelines are immune to ground movements, and therefore can be used even in regions with seismic activity.

The only limitation for such pipes is the temperature of the transported medium. It should not exceed +40°С (at +80°С polyethylene becomes soft). So for the installation of heating systems, you should choose other types of pipes.

How are polyethylene pipes connected?

Do-it-yourself HDPE pipe connection can be done using 2 technologies and depends on the purpose of the pipeline:

Features of a detachable connection

The detachable connection can be dismantled without violating the integrity of the pipe itself. The connection of HDPE pipes with compression fittings is most often used during the installation of various water networks. The principle of joining two pipes is that internal elements The fittings are crimped to create a secure hermetic connection.

The compression fitting includes the following structural elements:

outer threaded body;
ribbed, easy-to-tighten union nut, which is screwed onto the body;
sealing rubber ring, with good wear resistance;
a sleeve for pressing in, which allows you to securely fix the rubber seal;
clamping ring, made of a material that is more durable than low-pressure polyethylene - polyoxymethylin;

To carry out pipeline assembly work, an open-end wrench may be required to fix the fittings (in practice, fixing is almost always done manually) and a knife for cleaning the surface of the pipes.

The technology itself, how to connect HDPE pipes with fittings, is as follows:

The upper protective layer on the pipe is removed by special stripping, or the pipe section is simply cleaned from contamination, which makes it possible to guarantee best connection. The length of the leg must match the size of the fitting. A chamfer is removed at the end.
The union nut on the fitting is untwisted, after which pipes are installed in it.
When the union nut is installed back on the connection, the pipe will be clamped by the ferrule (this process is called compression). When fixing the ring, it is very important to control the force, otherwise the body will burst from excessive pressure.

Detachable connection of HDPE pipes without welding using fittings

It is advisable to use compression fittings in pipelines with a small diameter, where the dimensions of the pipe do not exceed 63 mm (although it should be noted that maximum diameter such fittings - 110 mm). If the connection suddenly has to be disassembled for repair, then the fitting can be reused. However, before this, the integrity of the clamping ring should be checked - if necessary, it can be replaced.

If it becomes necessary to join HDPE pipes and polypropylene products, fittings can also be used. Welding in this case is impractical, since the materials have different characteristics. The connection here can be made with threaded or compression fittings.

How to connect HDPE pipes to metal - flange connections

The connection of HDPE pipes with metal is carried out using flanges. This method is best used when low-density polyethylene pipes should be connected to an existing cast iron or steel main. Structurally, the flange is a steel product with a connector for installing a HDPE pipe. These can be welded bushings or cap elements, which are best used for those pipelines where it may be required quick dismantling(for repair, cleaning, elimination of accidents).

Two mounting methods can be used − locking connection or threaded flange. With the fixed connection method, the flange is mounted on a metal pipe, after which the HDPE pipe is placed in it, and then the entire structure is fixed thanks to the clamping ring. The clamping ring is provided with a rubber seal, which provides better sealing of the connection.

The threaded flange is a threaded pipe. There is also an additional seal for tightness. It is advisable to use a flange connection when installing pipes of large diameters, as well as when connecting polyethylene pipes to steel valves and pumps.

Important: During installation, the steel flanges must be free of burrs or protrusions that could damage the pipe.

Such connection methods are classified as detachable. It is advisable to use them when welding is not economically justified or is impossible due to technical features installation of a specific pipeline. For detachable connections low cost is characteristic, because specific devices or professional equipment are not needed here. In addition, the creation of detachable connections is possible even in a limited space, and depending on the tasks, you can choose one of the methods - connecting polyethylene pipes with fittings or flanges.

Connecting HDPE pipes with fittings video

And here is a video on the topic of our article, which shows the connection of polyethylene pipes with compression fittings.

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