Modern technology housing arrangement of heating, plumbing varied and include the use of pipes with high performance. For water supply and heating pipe systems used today as from conventional materials but a higher quality, and produced by the new technologies using polymers.
Modern heating systems are assembled from the following species and varieties of pipe:
- metal (copper, steel, stainless steel);
- PVC (polyvinyl chloride PVC, polyethylene PE, polypropylene PP, XLPE REH-);
- metal and plastic.
Let us consider the last group - metal tube for heating, is widely used both in the home and in the workplace.
The design of plastic pipes
MP-pipe as the other species of this group of materials characterized by two geometrical parameters:
- drift diameter;
- wall thickness.
Therefore, the description of the multilayer pipe constructions limited to the consideration of its wall structure - shell of two layers of polymer with an aluminum layer (0.2 - 0.6 mm), fastened by special astringent. Thus, an aluminum tube having a longitudinal seam formed by laser or ultrasound, having an inner and an outer sheath of polyethylene.
Longitudinal welding aluminum sheath can be made butt or overlap. shell docked butt higher quality, overlap - it is easier for technology, so products with an aluminum layer welded end to end, more expensive.
Polymer membranes provide tightness pipeline insulation and the transported medium can withstand a certain part of the pressure that It has on the coolant pipe and the aluminum pipe more adds structural strength, and also reduces the amount of linear deformation at temperature changes. In addition, the median sheath of aluminum, depending on the thickness, allows to give the desired tube configuration at installation, that is, to bend it at a right angle, and bending the aluminum will be fixed, and will not disappear after application termination efforts.
Varieties MP-pipes
Besides geometric characteristics, plastic pipes are different pictures polyethylene layer.
For the production of plastic pipes is used:
- conventional polyethylene - MP-tube with PE-R markings;
- resistant PE - labeled abbreviation PE-RT, indicating a good resistance to high temperatures;
- XLPE - marking material with PE-X, obtained from normal polyethylene by crosslinking, i.e. use of one of several special technologies, changing lattice bonds of the polymer molecules, thereby improving its characteristics (there are four main ways crosslinking designated Latin letters a, b, c and d);
- polypropylene - PPR-AL-PPR - species polypropylene tubes reinforced with an aluminum foil thickness of 0.05 - 0.1 mm, which does not fix the tube in the bent state after bending, but decreases the magnitude of the temperature elongations (PPR-AL-PEX - another subspecies, wherein the outer layer - polypropylene inner - crosslinked polyethylene layer - aluminum foil Same thickness).
Important! For heating and hot water supply pipes are used above all, except those marked PE-R - Metal of conventional polyethylene.
Designation type polymer layer is necessarily present on the outer pipe MP-labeling, which also contains the following information:
Also mandatory said information marking may include other additional information: a transport media (water only or both), date of production, lot number and others.
Technical characteristics of plastic pipes
Drift diameter metal pipes - the main characteristic of this material, which may be of the following values: 16, 20, 26, 32, 40, 50 and 63 mm. In household distributed first 5 MB sizes of pipes, the material, diameter 50 mm and more rarely used.
The range of wall thickness metalloplastika less diverse, ranging from 2.0 to 3.5 mm. The ratio of wall thickness and diameter is clearly seen after the information data in the table:
There is another value, tied to these parameters - the radius of the pipe bend.
During installation of pipeline bend possibility composition pipe material is an advantage that facilitates the work. MP-pipe bend in two main ways - by hand and benders, with the choice of method depends on the bending radius. However, besides performing bending technology, the magnitude of its radius is also due to the tube diameter and wall thickness.
The radius of bending metal pipes is:
- performing the manual - 80 - 550 mm;
- using bending tool - 45 - 180 mm.
The maximum value of MP-pipe heating water temperature due to the operating pressure. The heating and hot water systems where the water temperature reaches 95 degrees, plastic tubes have to be designed for a maximum operating pressure of 10 bar.
Important! Plastic pipes have interesting feature to adjust to the maximum time the magnitude of the working pressure, if its effect is constant, and subsequently withstand 1.5 times higher value.
The optimum temperature of coolant in the heating system is a value of 75 ° C, but at a stable value of MP-pipe pressure will be durable even at its largest in 95 ° C.
Temperatures from 95 to 110 ° C for metal pipes are not critical - in emergencies short-term the impact is acceptable, but is fraught with possible breach of the system and the formation of tightness leaks.
Durability compounds also reduce regular significant temperature gradients, especially freezing system, which is possible at a temperature -40 ° C.
mount technology
Heating of the plastic pipes or the water supply of the same material are specific only to the assembly means elements, fastening the duct to the substrate is performed by conventional methods, like the use of other components.
What is fitting
To assemble the heating elements or the water used in a single loop fittings - connecting the nodes, the structure of which depends on the purpose.
The system is collected by the three following types of fittings:
- detachable (they are also threaded, collet);
- Compression (conventionally detachable);
- Press (one-piece).
Pipe connection overmolded in turn divided into two subspecies installation (used in form fitting) - using crimping sleeves or slip-on type.
Split fittings
Compounds of this type are nodes reusable - they can be mounted and dismounted a number of times, so their value is higher than other types of fittings. The brass body of detachable fittings fixed to the pipe using crimping rings and gaskets.
Collet compound suitable for mounting cold water and, if k joints after assembly remains access, performing wiring hot water. In heating systems threaded fittings provide a leak path for 2-3 years, after which nuts must be periodically tightened, and on exhaustion of the reserve thread cutting device must be replaced by new.
collection algorithm
Pipe slice is put on the nut after it - ring, and then is pushed up to the stop body. The housing is installed a ring on top of it - a nut, which is wrapped first her hands and then the key.
Before the operation of the pipe section is processed special device - calibrator, reducing its geometry after a possible collapse during cutting.
compression fittings
Swaged fittings consist of a fitting and cap nut, is fixed on the pipe by the compression ring with a slit, and execution are conditionally detachable joints - if appropriate assembly can be easily disassembled, but when the next coupling assembly not sealing guaranteed.
It applied this method compound MP-tubes in the same systems as the collet joints - preferably for wiring tubes with cold water, and at the open location of connecting components - and hot water supply.
Compression fitting consists of the following components:
- a body with two or more outlets with an external thread;
- fittings (number of outlets in the housing) with a seal rubber rings inserted in the cut-MP pipe;
- union nut (number of nozzles);
- a compression ring with a slit (the number of screws).
compression fittings assembly process
Connected crimp the previous method does not differ significantly - mounting reliability provided by using the split compression (thrust) rings.
Installation requires no special training and possible to manufacture their own hands, the required minimum tools - two keys, one of which is adjustable, and the calibrator shears MP-tubes (Precision). Desirable bending tool, which reduces the bending radius of the tube, or - it is necessary to bend the tube manually, using one of the methods.
Precision scissor cut is performed on the planned location of the pipe perpendicular to the longitudinal axis. If MP-tube was acquired by the meter in a bay, the cut fragment arc aligned, particularly edge portions of a length of approximately 10 cm.
Then the slice is processed to recover calibrator hole geometry, impaired crumpling during cutting and chamfering at the outer edge of the cut.
unscrewed the nut and removed the split ring C fitting body. The end of the cut pipe portion is wetted to slide, it is put on the nut and the ring, after which the pipe fitting is inserted up to the stop with rubber seals, taken out of the fitting body. The snap ring is shifted by fitting, on top of it - union nut and the threaded connection is first assembled by hand, and then pulled the keys, leaving the left 1.5-2 turns for final sealing before the commissioning work. Reliability is provided by fixing the pressing action of a pair of threaded transmitted to the side walls of the pipe MP-compression ring.
Press fittings
To date, the press fittings are the best way of installation of heating metal pipes, which saves the tightness of the system in the entire range of operating pressures and temperatures. It is molded with a solid fixation assembly MP-pipe, which allows the use of press-fitting both in the open and concealed wiring piping heating and domestic hot water.
The connector assembly includes copper or brass body and the sleeve (2, 3, or 4) a stainless steel - design depends on the purpose of fitting and installation position in the system.
The hull shape can be different (cross angle, tee, socket) and depends on the type of compound. The sleeve provides the necessary strength - the element is pressed with a special device, after which a metal owing to special treatment to change its profile is almost impossible. To neutralize the various problems of the characteristics of ground currents between the body and the copper sleeve mounted steel gasket sealing ring - clip.
Pressing the fitting is carried out pressing jaws manual or hydraulic execution. hand tools cost several times lower than hydraulic, but the quality of the connection is not recognized - handmade and reliable.
Method pressfitting Fitting
The pipe is strictly perpendicular to its axis is cut at the place of a pipe cutter, then her butt processed - calibrator recovers sectional geometry, and performed an internal chamfer cutting edge. Upon completion of training end inserted into the pipe fitting to the stop, controlling the perpendicularity of the through inspection hole. The sleeve is captured clips mites and reduce their arms towards each other until it stops.
Important! Crimping press fittings made ticks the appropriate size, in many tool kits have set removable terminals for connection of nodes of different diameters.
At the end of the correct compression on the sleeve are two grooves on the circumference, and her profile becomes convex from the edges to the middle. The repetition of the pressing of the same connection is not allowed - Connection tightness will be compromised.
The question of self-MP connection pipe press fittings is not difficult, but the price of mites is high enough - to acquire tools even the manual versions for single use does not make sense, from these considerations, pressing pliers offer rental car rental locations tool.
Advantages and disadvantages of plastic pipes
The advantages of MP-pipes used for the device heating and plumbing are their following characteristics:
- sufficient ductility - easily carry out wiring in the desired direction;
- universality - hot and cold water, heating system (including underfloor heating);
- absolute anticorrosion;
- sufficient heat resistance;
- low specific weight;
- wide price range;
- availability of installation in the home;
- ease of maintenance;
- low heat;
- environmental friendliness.
With such a broad and not a full list of MP-tubes have advantages and disadvantages:
- relatively low longevity (15 years);
- freezing in the presence of water with the subsequent destruction (limited climatic zones topical application);
- relatively smaller steel pipes dependability compounds;
- Low fire shells of polymers.
conclusion
Despite a number of drawbacks, plastic tube with a correct choice of the field of application, the type of material and Quality installation will last long enough to justify spending more time on their acquisition and installation. Therefore, consumer demand for MP-material is reduced, and grows, particularly in connection with the regular appearance of new varieties with improved characteristics.
