Entrance steel doors. Production of entrance steel doors. Locking systems.

Kinds of entrance steel doors

Entrance steel doors (entrance metal doors) differ in their big variety. They can be arched by shape, they can be glazed with armoured or shockproof glass, can be in the form of transoms or side windows made of the same glass etc.

Metal doors are made hollow or filled with soundproof and heat-insulating material. There are constructions of steel entrance doors, the frame of which is fixed with concrete during installation, thus forming complete monolith with the wall. Such entrance doors cannot be knocked out.

Production technology of entrance steel doors

Any steel entrance door is based on rectangular frame with internal rigid edges. It is welded of steel profile. Steel sheets are welded to the frame. Though mechanism of entrance door is rather simple, each element of it plays a special role.

Entrance steel door consists of leaf, locking system, frame, filler, and can also have some decorative elements.

Nowadays leaf of entrance steel door is usually made on the basis of frame technology of two types:

Production of entrance steel door on the basis of rolled metal made of low-carbon steel, which increases bearing capacity of leaf and resistance to shock loads;

Production of entrance steel door on the basis of thinextruded profiles, which gives the leaf spatial hardness and lightness.

In the first and in the second case useful life of leaf depends mainly on the quality of raw materuals, and on their treatment and assembling.

Frames of entrance doors are trimmed with metal sheets from both sides. External sheet protects the whole locking system, being a direct obstacle to different cutting objects, that is why one shall pay attention to the thickness of this sheet.

Locking system of entrance steel door

The main thing in the entrance steel door is its locking system and its main part – lock. Three- and four-revolution level locks are considered to be a reliable protection from unwelcome guests. It is impossible to open them with master key. Locks with radial cylinders of extra secrecy are also good. But if you have installed them, take care that the area of cylinders is protected with armoured cover plates from both sides. From the outside such cover plate will prevent from drilling-out, from inside - from knocking out. There is another method to protect your door, it is disguise of lock in the cave of door leaf. It will not allow an intruder to define location of lock.