Why do I need a heating cable inside the pipe?

Heating cable for heating the water pipe inside / outside - a special conductor in which the resistance is regulated, depending on the ambient temperature.

In such a simple device, the property of conductors is heated when the current passes through them.

If the normal wiring is heated and can eventually burst, the heating cord is designed for constant heating.

The lower the temperature outside, the greater the resistance and the stronger the heat inside.

The heating cable is an indispensable element of the construction of drains, sewerage and all those pipes that it is desirable to stay warm in cold weather.

Let's figure it out in all its nuances: how it works, what it consists of, what kinds are, let's go to the selection and disassemble the installation.

Principle and

device heats cord is an electric heater in the form of a tape which has a composition of metal conductors separated byheat-dissipating matrix.

The matrix has several advantages:

• Continuous heating;
• The matrix increases / reduces the amount of generated heat, depending on the temperature outside the winding;
• The matrix does not overheat;
• Wire installation - arbitrary, does not depend on the matrix.

The cable consists of 5 layers:

1. Self-regulating matrix - a solid heating element made of polymer. It is responsible for heating;
2. Copper conductors - they serve to maintain a constant voltage;
3. Thermoplastic shell - isolates the matrix and conductors from abrasion and moisture;
4. Metal sheath - ground, shield conductors and matrix;
5. External containment.

Application, advantages and disadvantages

If you look at the cable through the prism of different applications and specific examples, once it becomes clear to its potential for use:

• Warm floor - in the assembly is placed directly under the floor covering;
• Help when curing concrete - a cheap cord is used, which after curing of the concrete remains inside;
• Heating the mirror - the cord acts as an anti-fog system;
• Protection of pipes in frost - the cord is laid in the pipe and constantly maintains the temperature above the freezing point. For sewage and water supply it is extremely important;
• Constant temperature in terms of technological processes - maintains the temperature by being submerged in oil, water, beverages;
• Element of drainpipes - helps prevent frost, crust formation;
• Heating of greenhouses - is recessed into the soil and creates a greenhouse effect, complicated installation is not needed.

The heating cable has the following advantages:

• Small section - can be used almost everywhere;
• It is easily bent - it can be pulled out, wrapped, put around the perimeter of any object;
• Insignificant losses of thermal energy;
• Can be cut to lengths of the required length;
• Can be laid outdoors, in liquids, in the ground.

The heating cable system is not devoid of shortcomings:

• Electrical safety - you must properly observe the grounding, protect the cable from mechanical damage;
• A poor-quality cord can easily overheat and a fire will occur. Such a drawback is a common feature of the resistive cord( about the varieties a little further on);
• It is undesirable to allow cable overflow when laying - even the best quality will fail.

Types of cables

There are 3 types of heating cable - resistive, zonal and self-regulating.

Resistive - as the name implies, the principle of cable operation is based on heating when overcoming resistance.

This cable is very flexible, has a high output power, and therefore it can be ranked and create a heat concentration per unit area - for a warm floor, for example.

This kind has one significant drawback - heat transfer is not regulated, which means there is an over-expenditure of electricity.

Zone - consists of two parallel wires.

A wire with a large spiral resistance is laid on top of each of the wires, which closes periodically on opposite sides, forming parallel heating zones.

Each such section is a separate heater up to 1 meter long. The thermal efficiency of the zone type of the cord is almost independent of temperature.

When operating a zone cable, do not overheat, which almost always occurs when the cable is overlapped.

Self-regulating its heating cord is the most profitable in all respects: heating depends on the external temperature of the environment, economically consumes electricity, it can be cut into parts of the required length.

Heat dissipation is up to 100 W / m, while it varies along the length of a single section - the separately taken part of the cord reacts to the outside temperature separately.

Video:

The most widespread due to its advantages and features of operation got a look, self-regulating its heating.

Selection and installation of

In order to choose the right cable, you need to know the thickness of the thermal insulation and the diameter of the pipes - there is a direct relationship between them( on the left - the pipe diameter, on the right - the minimum thickness of thermal insulation):

• 15 mm - 20 mm;
• 20 mm - 20 mm;
• 25 mm - 30 mm;
• 32 mm - 30 mm;
• 40 mm - 40 mm;
• 50 mm - 50 mm;
• 65 mm - 65 mm.

The larger the pipe / the thinner its thermal insulation, the more heat it will take.

When choosing a cable, you need to consider the following parameters:

1. Pipe diameter;
2. Pipe Material;
3. Thermal insulation thickness;
4. Heat loss of the pipe.

Now let's analyze the installation and its nuances.

Mounting inside the pipe:

• To insert the cable inside the water supply, an oil seal is needed;
• If the cord is fed from the top to the bottom, then fixing is not needed;
• If the cord is fed from the bottom to the top, then fixing is required;
• Any sharp edges( fittings, threads) must be avoided;
• At the point of insertion into the pipe we put the tee / adapter in compliance with the sealing;
• In the adapter we insert the sidebar and only after it we feed the heating cable.

Types and ways of fixing

Along the water pipe, the cable is laid in a straight line: one of its edges is tied around a thin wire / rod / of any thin long object and carried to the end for the entire length of the site, after being attached to both ends of the section.

Video:

You can lay the cable along the pipe in turns: avoid overlapping, observe the step, and you can fix only with aluminum tape!

Along the tube, you can stretch several rows of cord in a straight line - also attach only with aluminum tape. Anyone else will just melt.

In separate sections of the water pipe - near the flange, the valve, the fixing takes place in such a way as to maximally grasp the valve / flange along the perimeter, not to admit at the same time overlap.

To insulate the sewerage pipe, it is necessary to wind up with frequent turns with a short step - a pipe of large diameter, because for heating you need more heat per unit area.

Mounting methods:

• The cord is attached only with aluminum tape;
• On the pipe, the cable is fixed with separate pieces of adhesive tape every 30 cm, then wrapped completely with adhesive tape - this creates a large heat sink area;
• If the pipe is plastic, then first all of it is pasted with adhesive tape and only afterwards it is possible to install a cord over the pipe;
• The cable can be installed on a water pipe or sewer pipe with a herringbone. The herringbone on one side and on the other( you can simultaneously 4) warm up the thickest tube.

Installation of a heating cable - the ability to prevent the pipes, tanks from freezing.

And our feet are not an exception: install several rows of heating cable inside the floor and the floors will become one big heating element.

A sewage pipes and water pipes in the winter will preserve integrity: because of the cold, they will not crack, there will be no leaks, and therefore there will be occasions for urgent emergency work, when the window is minus not the first month.