A-level lock: At present, the A-level anti-theft lock keys on the market mainly have a flat key and a cross key. The internal structure of the A-level lock cylinder is very simple, limited to the change of the marble, and the marble groove is few and shallow. Anti-technical opening time within 1 minute, the mutual opening rate is extremely high. The marble structure is a single row of marbles or a cross lock.
Class B lock: The key of the Class B lock is a flat key with double rows of marble slots. The difference from the Class A lock is that the key surface has a row of curved and irregular lines. There are three main types of lock cylinders, computer double-row lock cylinders, double-row crescent lock cylinders, and double-sided blade lock cylinders. Anti-technical opening time within 5 minutes, high mutual opening rate. With a strong twisting tool, the lock cylinder can be opened within 1 minute.
Class C lock (Super Class B): The key shape is a single-sided blade internal milling slot, external milling slot key or double row + blade form. The lock cylinder type is a side column lock cylinder. It cannot be opened technically after 270 minutes by the Ministry of Public Security. , The regional mutual opening rate is zero (one in 16 million). The pinball structure is locked by double-row blades and V-shaped side posts; if the lock cylinder is opened with a strong twisting tool, the inner part of the lock cylinder will be destroyed, self-explosive and locked, making it impossible to open.
1. Class A anti-theft lock
The key with only a marble slot is an A-class anti-theft lock, among which the numbered key and the cross key are the most common. Although the lines on the key do not look like dots, the corresponding lock cylinder is a marble structure. The internal structure of this lock cylinder is very simple, limited to the change of the marbles, and the marble grooves are few and shallow.
2. Class B anti-theft lock
The key with both marble groove and milling groove is B-class lock. This kind of lock is generally equipped with a flat key, which is double-sided and double-row. The keys mainly include single-row anti-removal keys and single-row crescent keys. The internal structure of the lock cylinder is more complicated than that of Class A locks, and the anti-theft is more secure than Class A locks.
3. (Class C lock) Super Class B anti-theft lock
Super Class B lock is currently the safest level. From the perspective of the key, it is generally double-sided and double-row bullet slots with a blade or curve next to it. The workmanship of the lock core is strict and complicated. The relevant department monitors the technology to open for more than 270 minutes as the standard, so it can be used with confidence.
4. Inspection of anti-theft door locks
1. Check the security level of the lock: When purchasing, the business must be required to show the security level certificate of the lock used in the anti-theft door to see if it is a special anti-theft lock that has been tested by the public security department. Choose the security door according to the level of the lock.
2. Check the lock of the anti-theft door: there should be a steel plate with a thickness of 3mm or more for protection at the lock.
3. Check the length of the main lock of the anti-theft door: the effective length of the main lock tongue of the anti-theft door should not be less than 16mm, and there should be a tongue stop device, if not, it is unqualified.