How to weld rigid and flexible wires: description of the procedure

Power cables are used for the realization of the electrical wiring of different properties can be flexible (stranded) and rigid (single-wire) wires. Each type has its own list of core strengths and weaknesses in their properties, they are mutually complementary, that determines their main applications.

During the implementation of the wiring for various reasons, sometimes it is necessary to splice cables with different types of living.

The resulting splice should:

• be performed in a minimum time;
• not require to create sophisticated tools;
• provide the necessary degree of reliability in operation.

The latter requires the maintenance of a minimum contact resistance of the transition from one wire to another throughout the life of the wiring operation. Otherwise, increase sharply risks against overheating, which in severe cases, lead to a fire.

Why is it necessary propaivat area stranding?

Twisted wire during operation for various reasons, are always subject to more or less strong pulling and twisting effects, accompanied by loosening twist.

These processes lead to a decrease of the contact area connected conductors, which leads to an increase in contact resistance.

From School Course Physics it is known that the power released resistance R, is R =I2*R, Ie increase of contact resistance of badly made stranding necessarily leads to its heating.

This in turn causes an increase in resistance with a rate of about 0,4% / ° C. Formed a classic positive feedback, the process speed is increased, and he becomes an avalanche.

To eliminate such risks SEP prohibits the use of a compound of twisting wires, effectively requiring compulsory mechanical reinforcement connection area.

Permission is granted to use technology "screw", crimping method, welding, soldering. In the future, focus only on the latter method, the implementation of which, with the exception of maybe a soldering iron, do not require any additional tools.

The algorithm for generating the splice at great length all

There are several ways to obtain approximately equivalent splice.

We consider only the most popular one, which is a logical 6-step procedure.

1. With spliced ​​wire insulation is removed, the exposed core length is approximately 50 mm.
2. Cores cleaned gloss (preferably sandpaper in its absence is possible to use a knife).
3. Further straighten the rigid core, and swing the flexible conductor around starting from the edge of the insulation and bringing about the middle of the length.
4. The remaining free end of the rigid core is folded back and crimped pliers so as figure 1 shows.
5. Then the resulting splice conventional manner with rosin propaivaetsya tin as a flux.
6. The ready compound was wrapped with electrical tape or heat-shrinkable sleeve to protect, figure 2.

Formation of a splice in the absence stocks length

In the absence of a procedure of forming the length of the splice reserve a few changes:

1. With wire over a length of 15 - 20 mm insulation removed, cleaned of their gloss.
2. Litz wire is twisted, whereupon ludyat both ends with solder under rosin.
3. The treated ends is applied to each other and connected by soldering so as Figure 3 shows.
4. Ready to protect the splice tape or a heat-shrinkable sleeve.

To increase the mechanical strength of the resulting splice during winding of tape or shrink sleeve to the place of contact wires stack segment cambric or a piece of plastic rod, the ends of which extend beyond the end of the insulation of both wires at least 10 mm.