You will need
- professional tools;
- is a universal lubricant;
- - heating element;
- - sulfuric acid;
- - rags.
Before to Unscrew a rusted bolt, first check the instruments used. Head or adjustable spanner wrenches should be made of quality metal with a suitable coating. Unfortunately, cheap products too often break down, causing even greater problems and even damage the distressed details.
First, try to Unscrew a rusted bolt on system front to back. Tightly secure the wrench on the bolt, then suddenly turn it on against the axis of rotation, easily return to its original position and again sharp movement, try to twist it a bit. Manipulation should continue as long as the bolt literally will not penetrate the rusted part of the thread.
If the previous steps do not work, you should use a special penetrating lubricant, for example, is very popular WD-40. In its absence can also help turpentine, kerosene, gasoline, or oleic acid. Wrap a rusted bolt with a rag and densely fill the resulting design of the selected liquid. Leave the cloth for several hours, periodically rattling the bolt with a hammer for better penetration of the fluid into the structure of the rust. After that, the bolt can be unscrewed, if necessary using a system of "back and forth".
If after marinating in a special blend of the bolt does not want to get out, come to the aid of the knowledge of physics school courses. Use a soldering iron, heat gun, gas burner or if the detail sizes with a rusty bolt let, ordinary gas stove to heat the bolt up to the maximum possible temperature. Then let the metal cool slightly and remove the bolt. Sudden cooling can lead to rupture of the metal of the bolt or the part itself, however, this method is also applied.
If the physical failed, help can come only chemistry. In this case, around the protruding part of the rusted bolt nameplate a side of melted plastic, clay or paraffin. In the ring formed is poured a little zinc dust and poured sulfuric acid. Thus the bolt becomes a party to the galvanization process (this is also the school curriculum). As a result of this process, the bolt action of acid is not exposed due to the more active zinc, but rust is fully dissolved. Moreover, after conducting this experiment during the day the metal of the bolt will be restored due to the zinc.