How does a screw hold tight?
How the self loosening of screws can be prevented ??
What can I do against rust starting in the area of the screws??

Simply said, a screw works like a rubber band.
During set with the correct torque, the screw is stretched and holds the parts together.
Basically a thread is self blocking. This means, a screw does not fall out by itself. You can imagine this like two wedges laid on each other with the obliged surface - these wedges does not slip apart, when pressure is forced on the obliged surfaces. This all under the precausion that nothing is bouncing or vibrating.
What happens, when all is bouncing and vibrating and additionally some temperature comes into the game???? Our old cars do all this - even the new ones....

As we all know, every screw-joining will loosen itself under such heavy conditions - You can be sure.
OK, but what are we doing against it?BR> Just tighten it more. This will help in the first moment but it is the worst thing we can do. Except you have no other way. For example on the road during a journey.
Therefore we are using differnent washers (the easiest way of thread locking) and shims. The only common of these lockings is to claw in the surface of the joining item. This means, the surface will be damaged. If the surface is of iron as most of the chassis of our cars, there the rustworm has easy play to start. Trust me, You can be sure.

The other part of the game is called <seizing>.
For Example Yo have a waterpump fittet to an aluminium engine block. You can be sure that at least one bolt has seized and will brake flush with the aluminium block. The reason: differnet materials (iron and aluminium) and moisture from the cooling. This all will give an galvanic element where travel of material is common. This results in heavy corrosion in the tread and therefore seizing. As everyone will know, this is the best constuction that this screw will not come out voluntary. (I had to learn this the hard way)

REDRESS: chemical tread locking which is an anaerobic glue.
Important features:

• prevents damages on the surface because there is no need for spring shims or tooth washers.
• prevents entry of moisture into the treads

HOW TO USE:

• At trough boring: The thread lock will be applied at the end of the screw evenly around the outline. This results in evenly coating the inner of the nut.
• Tapped blind hole: a similar procedure, just approx. where the middle of the blind hole is suggested on the screw. This then will result in an evenly coated blind hole in the beginning.

IMPORTANT:

• Both threads have to be free of dirt and grease. Very helpful is degreaser, white spirit or laquer thinner (be carefull of car paint).
• The tread has to be coated evenly aound the outline.

Because this thread lock is an anaerob glue, it does not matter how long the bottle is open, but please be carefull to close the bottle after usage. This thread lock only hardens under lack of air in contact with metal.

WARNING:
Keep away from children !
Do not swallow!
This product is only intended for thread locking and nothing else. Any other usage will result in damage or may be harmful.