This article will introduce to you two aspects of safety hammer, one is the use method, the other is the use of precautions.
Application of Safety Hammer
The conical tip of the life hammer is mainly used. Because the contact area of the tip is very small, when the glass is smashed by the hammer, the pressure of the contact point on the glass is quite large (similar to the principle of the thumbtack), and the car glass is slightly cracked by a great external force at that point. For toughened glass, a little cracking means that the stress distribution in the whole glass is destroyed, which can produce numerous spider-web cracks in an instant. At this time, the glass fragments can be removed by a few smashes with a hammer.
Cautions in the Use of Safety Hammer
Because the middle part of tempered glass is the strongest, the corners and edges are the weakest. Therefore, when danger occurs, the best way is to hit the edge and corner of the glass with a safety hammer, especially the middle part of the edge above the glass. Once the glass has cracks, you can knock more. It is said that about two kilograms of pressure can break the edges of tempered glass.
When you take a long-distance bus, it's better to sit close to the safety hammer, the safety door or the roof exit. If you want, you can look carefully at the instructions for opening the safety door, because in case of an accident, you can't look at the instructions calmly.
Cars equipped with safety hammers can still play a role. Private cars equipped with safety hammers should be placed in an optional position.
In case of an emergency, the driver should drop the hammer at the left and right central positions from bottom to top two-thirds in order to ensure a rapid escape. The strength of hammering glass with safety hammer will be obviously stronger than that of pebbles and other blunt instruments. Generally toughened glass can be broken.