Recently, plastic pipes have become more common. They are used for the installation of hot and cold water supply networks, as well as for the installation of heating systems. In order to combine pipes and connect them to plumbing devices, different connecting elements are used, which include collet connections.
Main advantages
Collet-type fittings are able to provide long-term reliable connection of component pipelines for various purposes. At the same time, no special tools and sophisticated equipment are used. Such clamps can be used for installation of pipelines and when connecting plumbing devices.
What is fitting and collet?
In order to understand by what principle collet fittings work, you should understand what a collet and fitting are. The design of the first is ideally suited for use in joining cylindrical parts. This is a metal sleeve. On its side there are special cuts. They form springy petals. Thanks to the latter, the collet presses on the inner walls of the pipe. Its outer surface is pressed against the walls of the cartridge fitting.
Collet joints that work according to the above principle are also called clamping. But if we consider the fitting, then under this term the connecting element is hidden. It is used to create piping systems for various purposes. Fittings of this design are used to solve various problems. This should include:
- creation of corner joints in pipeline systems;
- connection of pipes of different and identical diameters;
- the connection of pipes with equipment and various plumbing devices, among the first it is necessary to distinguish: counters, filters, screens, pumps.
Collet connections are highly reliable. This is ensured by a collet, which presses on the inner walls. The external fixing nut is also responsible for this. If you create a pipeline using such a connection, then among its properties will be:
- durability;
- reliability;
- tightness.
Classification of collet clamps and types of pipes
Collet connections, depending on the purpose, can be divided into three categories:
- for construction made of semi-solid materials;
- for pipes made of hard materials;
- for soft plastic systems.
This classification allows you to choose clamps for connecting pipes of various types. Such compounds can be made on products made of hard metal, polypropylene, softer plastic and HDPE.
The collet connection of pipes allows you to choose elements for systems of various types. Such a connection can be used even by a layperson.
Instructions for use
When choosing clamps for mounting piping systems, the diameter of the pipes should be taken into account. This indicator for fittings should correspond to the transverse size of the pipeline, the tightness of the connection and reliability will depend on this. In order to determine the number of elements and in which place the straight fitting will be used, and in which - the corner fitting, you need to prepare a drawing of the pipeline system. Once it is in your hands, you can understand how the areas of the future system will be located.
At the next stage, you can start cutting the pipe into segments of the required length. A clamp should be selected for each pipe joint. Installation for which fittings will be used is carried out in a certain sequence. At the first stage, the collet should be placed in the inner part of the pipeline. A special nut is screwed onto the outside of the connecting element. The collet clutch will act in a certain way. The pipe will expand from the inside with its inside, while the outside can be squeezed with a nut. With the other pipe used in the formed joint, the same steps should be performed.
The collet connection for plastic pipes has a strong effect on the elements of the pipeline, so it must be used carefully. If the fastening nut is overtightened, you may run into the fact that the pipe will simply burst. Therefore, when using clamps that will be installed on plastic products, the force should be adjusted. This is especially true for HDPE pipes. The force must be measured when tightening the fastening nut.
Reusable
Quick-release collet joints are also good because, unlike welded joints and fittings, they can be used repeatedly. This distinguishes this technique from that which involves the connection of plastic pipes by heating. This important quality of the clamps makes it easier to repair the pipeline. The quick-detachable collet allows you to use the fittings repeatedly, so replacing individual sections, avoiding dismantling the entire system, you can quite simply.
However, such clamps also have disadvantages. The most significant is the fact that the connecting elements weaken with time. This can cause leaks in the systems. It will not be difficult to fix such a problem, for this it is necessary to tighten the collet fitting. Due to this lack of clamps, it is necessary to place them in those places where quick access to the system is provided. Fittings cannot be used inside walls and other building structures. Fittings are tightened to improve tightness approximately once a year.
Additionally, about the features of the connection of pipeline elements
The collet connection of metal pipes is reliable. It can be used in conjunction with pressure and pressureless pipelines. Docking can be performed so that metal and plastic pipes are connected into a common system. To do this, the ends of the elements to be joined should be cut off. The cut should be smooth and perpendicular. A coupling is applied to the joint.
The central part of the fitting should be located at the junction. The pipes should be marked with a marker that will indicate the position of the coupling. The ends of the pipes and the sleeve are treated with silicone grease. The first pipe is inserted into the coupling. The second pipe is aligned along the axis with the first, a coupling is sliding on it. When putting on the coupling, you should be guided by the mark applied.
Collet Features
The union with a collet connection has an external thread with an external hexagon. Nominal diameter is 6 mm. The sealing threaded connection is coated. The assembly position can be any. The design works on a reciprocating principle. The operating pressure range varies from 0.95 to 6 bar. The operating pressure, depending on the temperature, is equal to the limit of 0.95 to 14 bar.
There is one note per working environment. It lies in the fact that lubrication is possible. The material has one drawback, it has a low resistance to corrosion. The basis is alloyed stainless steel. The body material is nickel-plated brass. Ambient temperature during operation can vary from - 10 to + 80 ˚.
Description of cylinder grip
The collet connection of a gas cylinder is sometimes also called a choke or rod. People call it dichlorvos. Such cylinders are intended for special mobile kitchens. This connection allows the use of the cylinder in the burners, however, you should additionally purchase an adapter, which sometimes comes in the kit.
The collet bottle has thinner walls than a threaded one and is sometimes used at the connection to the burner, which can cause installation problems. As practice shows, in dichlorvos cylinders the fuel is of poor quality.
Types of elements for metal
The collet connection of metal-plastic pipes can be represented in three types. The use of such products is effective in conjunction with various heating and water supply systems. The first can be water and steam. The connection of pipelines can be carried out in technological systems, irrigation structures, etc.
Where there is a metal-plastic pipeline, there is a need to use special collet elements. They can be submitted:
- corners;
- straight grips;
- tees.
Corners are designed to connect parts of the structure at right angles. The fitting may have an internal or external purpose. The straight collet is designed to connect two segments in a sequential order. Three products can be connected using a collet-type tee, which will go in series and at right angles.
Why choose collet fittings
Collet parts for connection are selected for several reasons. The first is the presence of o-rings in the housing fitting. With their help, high sealing compounds. The material at the base of the fittings is of high quality. Installation is available even to a beginner.
The design provides for a split crimp ring. With its help, the clamp is carried out smoothly, and the design is not deformed. There is no electrical conductivity, because the collet-type fitting has a special dielectric gasket.
Availability, Durability and Reliability
Collet fittings are chosen for several reasons. One of them is low cost. This parameter is the sum of the price of the clamps, as well as the cost of their installation. To perform the work does not require the use of expensive equipment and special tools. A rather important factor is the possibility of replacing the connecting elements, if necessary. These works will not be associated with serious financial costs.
Buying such fittings of almost any diameter today is not particularly difficult. In today's market you can find clamps of any size. They are intended for pipes of different materials. You can quickly learn how to connect elements using clamps.
The connection created is durable under normal operating conditions. The pipeline has served for more than a dozen years. Only high mechanical loads and corrosive processes can disable it. The advantage of collet clamps is also their reliability, as well as exceptional tightness.