pipe insulation heating device, including external, is an important component of quality of housing and heating equipment is performed without fail. The necessity of this operation is due to many factors, degree of influence on the efficiency of heating an apartment or house depends on the circumstances.
Modern technologies allow insulate pipes heating on the street alone, examining the characteristics of the used thermal insulation materials and methods of installation.
insulation function of external heating pipes
Purpose of the heat insulating coating of the pipeline has several components that affect not only the efficiency of the heating system, but also on its operational safety, service life of the heating equipment. To the requirements for insulation coating were clearer, consider the more functions they perform.
Reduced heat loss
The efficiency of home heating system depends on many factors, including the magnitude of the heat. One of the components is the heat volume of heating medium in the return transit medium part of the energy when moving from the heat generator to the heat exchanger. Simply put, hot water or steam, moving in pipes from the heating boiler to the radiators, partially cools giving heat to the environment (air, wall material, soil, etc.) through the wall pipeline. And, the higher thermal conductivity material manufacture of pipes, the heat loss will be large. Therefore, the heating pipe needs additional heat insulating sheath, which prevents heat transfer between the coolant and the environment via the pipe material.
Frost protection
In the heating system in the off-season may force some circumstances be water, which will damage the conduit zamorznuv in the circuit during periods of inactivity of the boiler at the first frost. pipe insulation significantly slow down the process, saving a few days or weeks the water temperature in the system above zero.
Interference with the formation of water condensate
Thermal insulation pipe eliminate the formation of condensate on it at ambient temperature drops if the heating system is not free from water, and thus protect the tube from corrosion outside.
Protection against thermal burns by direct contact with a heat conductor
The shell of thermally insulating material, by definition, can not have a high temperature and eliminate the possibility of accidental contact with the burn of the human body with the hot conduit.
Neutralization geometric deformations
If the wiring is formed inside the heating system of building structures, elastic sheath pipe will assume temperature deformation tubes and protects the outer wall from exposure to finish it on the inside of the cyclic compression-expansion during on-off heating.
Requirements for Thermal insulation materials
Given the importance of the role of thermal insulation for pipes and heating systems, the need for quality of its devices, due to the listed functions, to the insulation materials must meet the following requirements set out in the SNIP 2.04.14-88 "Thermal insulation of equipment and pipeline ":
- low value of thermal conductivity - determining the suitability of material condition to perform basic tasks (insulation);
- sufficient thermal stability - the ability of a material to maintain its structure and physical characteristics in high (in the home - 105 Production - to 700 deg. centigrade) temperatures without reacting with the contactee substances without becoming catalyst percolation any chemical processes and without emitting harmful substances.
- chemical stability - the ability to react to a material resistant organic substance;
- sufficient hydrophobicity - water repellency, prevent getting wet insulation layer, so long as the filling water material makes it an excellent conductor of heat, at the same time contributing to the destruction of the pipeline under the influence corrosion;
- vapor permeability - the ability of a heater to rapid drying in case of direct contact with water;
- airtightness - characteristic that excludes filling of insulating material under the influence of wind dust particles that increase thermal conductivity (all solid insulating materials comply with this requirement, the soft - need additional arrangement protection);
- durability - the material must meet all of the requirements throughout the expiration date specified in the instructions for use.
Types of thermal insulation materials for execution pipelines
The execution of thermal insulation materials are divided into the following types:
- roll;
- sheet (in the form of mats);
- Kozhukhovo;
- liquid.
Rolling insulating materials - coiled into a roll a certain thickness and width insulation strip, having a base foil or without it.
In pipe insulation roll is wound spirally or (only in horizontal sections) laid longitudinally on the pipeline with a connection edge and under the pipe fastening or collars wire. If the foil material, the foil layer insulation suit out, but it does not provide adequate protection of the material from the precipitation, so the question arises, what to isolate the heating pipe in the street from moisture. This problem is solved by installing the pipeline over the foil material metal shrouds of galvanized iron.
Sheet materials are used as well as longitudinal roller with laying, the use of protective covers over them also due to the need of protection from moisture and mechanical damage.
Jacketed insulation may be hard or soft performance.
Melt proofing materials jacketed execution is a hollow cylinder with a certain wall thickness having a two or four sides of the longitudinal sections of the locking profile. The diameter of the cylinder cavity is performed under a certain pipe dimension.
Soft materials for thermal insulation are flexible cover to the wall of a predetermined thickness having a longitudinal section or not. A flexible heat insulating sleeve is put on without cutting the pipe to its mounting, and the incision allows insulate existing pipeline.
Liquid materials for thermal insulation of pipelines in the street are divided into:
- sprayed;
- coloring.
The first type is applied by means of special spray device gradually increase the heat insulation layer to the desired value.
The second type is used as a layer applied conventional paint roller or brush.
Each of these types of thermal insulation has a variety of differing materials production, production technology, physical characteristics, cost, and so on. g., as manufacturers are constantly improving the insulating properties of the produced funds. The modern market, depending on the operating conditions of the pipeline, allows you to choose the material that best meets the requirements of a particular situation.
Variants of a heat conductor located in the street
During the construction of private housing, there is a situation where it is necessary not only to breed and mount Heating system in the rooms of the building, but also to bring it to the adjacent residential or commercial buildings.
The second situation - is connected to the housing extending close to the heating duct or use autonomous heating boiler is located in a separate structure-boiler.
In such cases, the pipe installation between the buildings produced in the following ways:
- open (overhead);
- underground.
Each option laying of pipelines has both common to all situations, the principles of the production of insulation and unique to his work performance nuances. Thus any method for mounting and insulation of steel pipes provides compulsory preliminary preparation of the pipe surface - cleaning and applying a protective anti-corrosion refinishing.
Open (above ground) way
Open method of laying a pipeline includes its location on concrete or steel supports certain height set with the calculated step. Pipe-laying directly on the ground is only permitted in the construction of temporary roads.
When choosing a heat insulating material is necessary in this case, except the coolant characteristics, guided and availability factor of the pipeline in terms of probability of random insulation damage. If the tubes are arranged on supports above human growth, they are more protected than the low mounted available for human and animal conduit. Therefore located at a low altitude tube housings to be selected from a larger thickness galvanized metal.
Last but not least is the equipped thermal insulation and aesthetics, so used to protect the guards from roofing iron zinc coating without undesirable - they will periodically coated with a protective lacquer layer.
Important! If used as insulation foam conduit shell is a flammable material, the insulation of foam plastic arranged transverse discontinuities are filled with non-combustible material, for example, mineral cotton.
underground method
This technology is divided into two subtypes:
- channel - mounted conduit located underground in a sleeve accepting the weight of the soil;
- ChannelFree - thermally insulated pipe is placed directly into the dug trench.
Duct mounting method significantly increases the cost of the work and in private homes are not used.
Laying pipelines underground produced below freezing ground, and for insulation of pipes is not used permeable material (mineral wool) which can be impregnated with the flooding water and lose insulating properties.
Varieties of thermal insulation materials and methods for their use for thermal insulation of pipes outdoors
The range of thermal insulation materials, despite higher their performance requirements, today it is very wide, so the guide criterion when selecting than insulate heating pipes outside, becomes budget.
polyethylene foam
Foam (PES) reasonably considered one of the most efficient thermal insulators because its thermal conductivity of only 0.035 Watts / m2 deg. C - it is twice lower than that of mineral wool (0.07 W / m2 °. C). The consumer of such polyethylene is available in rolls, sheets in the form of sleeves, covers of various sizes.
PES elastic bubble structure of the reel when it facilitates the performance of the insulation on the shut-off valve and piping complex configuration, as it allows to cut into the material of the necessary bandwidth and to wind it the problematic nodes. Polyethylene parovodonepronitsaem, so is not only heat, but also the waterproofing coating.
Specific gravity PPE, depending on the structure is 32 - 35 kg / cubic meter, however insulating sheath thereof does not create a significant load on the pipeline and the support..
Despite the fact that the polyethylene can be set on fire, its flammability is low (Class D-2), and when ignited in No additional sources of fire foam quickly extinguished, while allocated to them by burning matter little toxic.
For device insulation straight pipe liner convenient use of PPE (a lateral notch or without it), as tubes winding roll pictures with the necessary technological overlaps require additional strengthening layer of insulating or binding wire clamps and looks no aesthetically pleasing.
When the price of a variety of advantages of the PES is not high, which causes its high popularity among owners of private houses.
penofol
This insulation is a type of the PES and differs from it in the presence of the one side of the foil layer, which is a reflector of heat waves, which increases thermal insulation, as well as hydrophobic properties shell.
Thermal insulation of penofol - PES foil is also produced in the form of rolls, sheets and cylindrical shells.
Important! Using polyethylene foam and penofol limited upper use temperature limit of 85 degrees. This value is sufficient for the use of materials in pipelines with independent heating system, but higher Central heating temperature characteristic deteriorates polyurethane backbones and makes it unsuitable for use in data conditions.
Mineral wool and products based on it
Insulate outer tube or an ordinary heating foil with mineral wool, winding line a strip of this material with detent binding wire, is the oldest method of insulation. But the popularity of this technology, thanks to the relatively high efficiency of its use and availability, costs, high until now - the choice of mineral wool as an insulating material in the large amount of work it is justified.
Mineral wool produced three varieties:
- glass wool;
- stone;
- slag.
The first two species meet most of the requirements for thermal insulation - have low thermal conductivity, are neutral with respect to the insulated surface, sufficiently elastic, chemically resistant and fireproof. As for the variety of the slag material, the process of its manufacture causes the presence of such a residual acidity of wool which negative effect on steel pipes - tubes therefore have to cover the special paint, which negates the advantage of a slag wool price.
However, all three varieties of mineral wool in varying degrees permeable and hygroscopic, so the insulation of these Materials must be protected with covers from galvanized steel, which simultaneously will be protected from mechanical and damage.
polyurethane foam insulation
Polyurethane foam (PUF) in texture made resilient (foam), rigid and sprayed. As hard insulation is used and sprayed polyurethane - effective and functional insulating material, with more than 30 marks.
All brand foam combine the following advantages:
- breathability;
- chemical resistance (higher than the polystyrene-foam);
- low moisture absorption (good water repellency).
Rigid polyurethane is produced in the form of modular shell-shell or cylinder with a mounting slit having a certain size, with the foil outer surface. Products are superimposed on the pipe and fixed clamps, sealant or heat-resistant self adhesive inner surface.
Also manufactured pipe in which thermal insulation foam with a protective sheath already formed - so called pre-insulated, are connected together by welding, followed by isolation of a welded compounds.
Sprayable foam is applied to the previously prepared surface of the pipeline special spray device layers and at least pour point, increasing the thickness of the insulating layer to calculated value. To perform thermal insulation of this technology requires special expensive equipment and protective clothing, so it is not used in a domestic environment.
foamed rubber
The raw material for this high-quality material is synthetic rubber, cost manufacture which is much lower than the cost of a natural material, but the quality characteristics as high.
Properties of foamed rubber:
- high elasticity at a large headroom tensile strength;
- low specific gravity material - 40 - 80 kg / cu m .;
- high insulating characteristic;
- no shrinkage in service;
- low flammability;
- zero vapor and water-resistant;
- chemical inertness.
The rubber insulation is manufactured as a web material, sheets of a certain format and-liner tube under standard pipe sizes. When using foam rubber insulation as heating pipes on the street, it is necessary to use protective housings of galvanized corrugated iron, which will protect the material from contamination by dust and mechanical damage, including vandalism.
Price range rubber insulation, depending on the thickness and the manufacturer, and is wide enough to select the material with the objective value of the price / quality ratio.
conclusion
A huge range of thermal insulation materials demonstrates the importance of the implementation of the protection of pipelines and heat demand of the means to achieve this goal.
Important! Most modern materials suitable for use in the home, allows you to work on the insulation yourself. And yet, before embarking on this operation, it is advisable to consult as to insulate the pipe heating on the street, the professionals already imeyushih experience with your chosen kind of insulation coverage.