When installing pipelines, thermal insulation is necessary for pipes in order to reduce heat losses or maintain the temperature of communications. This is essential for daily safe operation. If this is not done, then no one can guarantee that the system will work smoothly in winter and will not fail at one moment.
The thermal insulation of metal pipes prevents the possibility that the liquid in it will not freeze at low outside temperatures. This will also prevent condensation from forming on the surface of the pipe.
Important! The requirements for thermal insulation are set out in the safety regulations. If gas is transported through the pipeline, then heat insulators are used in various versions.
It is possible to isolate such a pipe by covering it with a special varnish or paint. But in practice, protective material is more often used, so that certain requirements can be met:
- Monolithic insulators are used, which evenly lie on the pipe.
- Working materials must have a low moisture absorption coefficient, and the waterproofing properties must be high.
- The material must resist the damaging effects of ultraviolet radiation well.
Insulation is clearly regulated in the relevant regulatory documents, which are called building codes and rules (today these are sets of rules that are an updated edition of SNiPs). These documents contain the technical characteristics of the material for the heat insulator and a detailed methodology for performing work.
Type of heat insulator
This type of work is carried out by heat insulators in the following forms:
- separate segment;
The pipeline can be thermally insulated using the following types of insulators:
- Mineral wool.
- polyurethane sealant.
- Pipe heater.
- Liquid expanded clay.
- Basalt wool.
This is not a complete list of heat-insulating materials. The construction market is subject to constant renewal with the advent of new, more modern materials.
Use of mineral wool
This is the cheapest material with which it is easy to carry out installation work. It is difficult to disagree with the fact that this circumstance is a pronounced positive moment. Work is carried out in compliance with the following requirements:
- A cross section of the roll is made. Strips 200 mm thick are formed, with which the pipe is wrapped. First, mineral wool is laid, and on top of it — fiberglass.
- The technology of laying mineral wool is carried out evenly, preventing its wrinkling.
Large diameter pipes are insulated in this way. Since cotton wool actively absorbs moisture, it quickly rots. Therefore, the insulation of pipelines with mineral wool is carried out only in cases where the heating main passes above the ground or indoors. This method is not used to isolate the sewer system and pipes with a small diameter. It is capable of igniting at high temperatures, so you should refrain from using it near stove heating, as well as in places where electrical cables pass.
Mineral wool exists in two types:
In the first case, the material for its manufacture are rocks. For the manufacture of glass wool, cullet or staple fiber is used, the basis for the manufacture of which is quartz sand.
External heat pipes
If the pipes are laid externally, then roll-type mats are used for thermal insulation. The application of liquid heaters has a certain ease of use. These include epoxy pipe insulation.
Powder or liquid coating has advantages over other types:
- Increased resistance to abrasive wear.
- Impact resistance.
- High temperature resistance.
- Anti-corrosion protection.
The linear sections of the pipeline are covered with a heat insulator with a galvanized casing.
Technological pipelines are insulated with foam rubber tubes or rolls. The insulation is carried out in several layers. Their number depends on the total required value.
Of particular interest is thermal insulation with the application of a cover layer.
The use of thermal insulation for pipe insulation does not allow hot water to cool down during its long journey from the source to the consumer. They are used for almost all types of pipes:
- polymer composite.
When performing such work in a private house, it is better to use pipes that have pre-insulation. In this case, self-adhesive insulation is used. An additional winding will help, for which you can use aluminum tape.
Before performing work, it is required to calculate heat losses. This takes into account the temperature that the coolant has and the temperature parameters of the surrounding air.
Good thermal insulation properties can be observed in polyurethane foam and glass wool. They are highly efficient.
Insulation of metal cold water pipes has the main purpose of preventing the appearance of moisture on the surface. Condensation protection is essential to prevent rust from developing. It leads to corrosion of the metal and, as a result, to the complete failure of the pipe.
Use of polyurethane foam
Foam polymer-mineral insulation has excellent environmental properties in the presence of high efficiency of its use as a heat insulator.
This type of insulator has many positive aspects:
- neutral smell;
- not susceptible to the damaging effect of the fungus;
- resistant to aggressive substances;
- does not have a harmful effect on the human body;
- manifests itself as an excellent dielectric;
- has good resistance to various mechanical influences.
If the pipes have a large diameter, then its application is carried out by spraying. In this case, the insulating layer is continuous, without a seam. The use of this method guarantees the exclusion of maximum heat loss. Spraying is carried out using special equipment. The spraying process is simple and short in time.
For pipes of small diameter installed in the apartment, a polyurethane foam shell is used. At the same time, a high level of thermal insulation is achieved. This method has a relatively low cost.
The use of polyethylene foam
In the market for such materials today, he occupies a leading position. It is applied to isolation of pipelines of any appointment. It looks like a finished shell, which was shaped like a pipe. She, as it were, envelops the pipe, protecting it from the action of harmful factors.
Such a shell has a seam along which a cut is made during installation work. After their completion, the shell is glued again.
Application of glass wool
This material has all the properties that meet the requirements for heat insulators. Rolls are used for thermal insulation. If we consider this material as the main means for thermal insulation, then with its use the cost of work increases slightly. This is due to the need for additional measures. Such works are longer in time.
Positive aspects of using glass wool:
- material can be used for a long time;
- has a high resistance to the vibration factor;
- high resistance to chemical and biological agents.
Before carrying out work on the thermal insulation of pipelines, it is necessary to draw up an estimate. It will reflect the step-by-step production of the entire scope of work. The result will be the total cost.
Thermal insulation works are carried out in accordance with the current regulatory building documents. If the work is carried out correctly, a guarantee is achieved that the desired energy efficiency will be achieved. The period of useful operation of the pipeline will increase significantly.
Various materials are used during installation work. In doing so, certain factors must be taken into account. Of decisive importance will be the purpose for which the pipeline is planned to be laid.
For example, if the pipeline is expected to have a heat carrier with a high temperature, then it is better to use cylinder insulation. A polyurethane foam shell is quite suitable for these purposes. As an additional tool, laminated foil cardboard or foil is used.
The application of internal insulation for metal pipes is carried out only in the factory, in strict compliance with regulatory indicators. Internal isolation allows to keep all operational characteristics of the pipeline. Most often, products with this type of insulation are used for laying underground pipelines.
Separate stages of work production
The work is carried out in compliance with the following rules:
- It is necessary to start thermally insulating the pipe only after the completion of all installation work (locksmith work, welding).
- The surface of the pipe is manually cleaned using special brushes. Mechanical sandblasting can be used. After that, the surface is subjected to degreasing.
- Welds must be tested for strength and tightness. In addition to visual inspection, hydraulic pressure tests are carried out. Special equipment can also be used for control.
- Then special compounds are applied to the surface. An example is an epoxy primer.
Recently, a method of insulating water and sewer pipes using a heating cable has gained good popularity. This method is most relevant in regions with severe winters. There are types that independently regulate the heating temperature. For greater energy savings, it is necessary to install a thermal relay. But the presence of such a cable still implies the need for high-quality thermal insulation. Without it, uncontrollable expenses will take place.