Select the security door to see several indicators

Wang Liyang

The full name of the security door is called "anti-theft security door". As the name suggests, it should have anti-theft and secure performance. But in fact, the anti-theft capability of the security door is also high or low. How to choose qualified products in a wide variety of security door market? Han Zhibao, president of Nanjing Unlocking Association, introduced several principles to readers.

Whether there is anti-theft level on the inside of the door, the new national standard will change the three levels of the original security door to four grades: "A", "B", "C" and "Ding". The highest level is Grade A, which is successively decreasing. The anti-destruction time of the Class A security door is not less than 30 minutes, the B level is not less than 15 minutes, the C level is not less than 10 minutes, and the D level is not less than 6 minutes. The anti-theft security level of the new national standard is represented by the four letters “J”, “Y”, “B” and “D”, which are generally marked on the inner side of the hinge side of the security door, and the height from the ground is 1600 mm ± 100 mm. The location is a permanent fixed sign. When selecting a security door, be sure to see if there is such a mark on the inside. If not, it is likely to be only a normal steel door.

The number of locks and the locks of the locks are mainly based on the number of locks, that is, the number of locks. When the key is turned on, the point on the door leaf is the lock point. The new national standard stipulates that the number of locks between the door frame and the door leaf, and the security doors of A, B, C and D should be no less than 12, 10, 8 and 6. In theory, the more lock points, the greater the tamper resistance, but it does not mean that the more security locks, the more secure the security door. Because the lock points of the security door are controlled by the lock cylinder, even if there are 12 lock points of the Class A security door, all the lock points are controlled by a lock cylinder. Therefore, when picking the security door, you should check the anti-theft level standard of the lock. China's current lock grades are divided into three grades: A grade, B grade and super grade B. Super grade B is the best. In addition, the length of the main lock should not be less than 16 mm.

The door thickness steel plate is another important criterion for judging the quality of the security door. The new national standard stipulates that the thickness of the steel plate of the security door frame should be more than 2 mm, the thickness of the door body is generally above 20 mm, and the weight of the door should generally be more than 40 kg. The thickness of the specific steel plate is as follows: A, B, C, and D are respectively selected to be 2 mm, 2 mm, 1.8 mm, and 1.5 mm. In terms of materials, copper security doors are the best and most expensive, followed by stainless steel security doors and aluminum alloy security doors.

The internal structure of the door body wants to have a more comprehensive understanding of the security door. It is advisable to remove the cat's eye, the doorbell box and other components to see the internal conditions. For example, you can look at the thickness of the steel, whether there is a filler that can play the role of fire prevention, sound insulation, etc. It is best to see if the connection between the front and rear panels of the door is normal, whether there is a gap or the like.

Whether there is a smash-proof sleeve or a cat-eye device that wants to strengthen the security level of the security door, you can take some measures by yourself. For example, add a tamper-proof cover to the door lock, or load a cat-eye device on the cat's eye to achieve a higher level of safety for the security door.  

NY250 Asbestos Rubber Gasket for Oil-Resistance 

Description:NY250 Asbestos Rubber Gasket for Oil-Resistance  as oil resisting Sealing Gasket materials,it is for widely range,and it made by  asbestos fiber with oil resistance synthetic rubber mixture,compression heating and molding it in thick paper fashion. 

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4100×1500mm; 4500 x 1500mm;2000×1500mm; 

1500×1500mm;1500×1000mm;1270×1300mm; 3810×1300mm 

Thickness:  0.5~6.0mm

Technical data:

Lateral Tensile Strength MPa      â‰§11.0    

Compressibility %                        7~17  

Recovery%                                   ≧45  

Density g/cm³                           1.6~2.0  

Normal temperature softness   No cracking  

Oil Resistivity Test:

Immersion IRM903 Oil keeping 5h (149℃)

Lateral Tensile Strength(MPa)       â‰¥ 7.0  

Weigh gain rate(%)                  â‰¤30  

Immersion ASTM Fuel Oil B keeping 5h(21-30℃)

thickening rate (%)                 0~20  

Oil sealing properties under normal Temperature

Medium:RH-75 Avgas  

Pressure:   10Mpa  No leaking keeping 30 minutes  

Nitrogen Leakage Rate ML/(h•mm)≦300 


 Product photoes:

NY250 Asbestos Rubber Gasket for Oil-Resistance

  NY250 Asbestos Rubber Gasket for Oil-Resistance

Ny250 Asbestos Rubber Gasket For Oil-Resistance

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