There are M4-M 16 diameter (the diameter of expansion plug is the same as that of drill bit when percussion drill is used) * *13 type, and the length ranges from 20mm, 30 mm, 40 mm, 60 mm, 80 mm, 100 mm,120mm. Therefore, there are thousands of specifications and models, and you can choose them according to your needs and uses.
When drilling, the depth is equal to the expansion pipe plus 3mm to 5 mm, except that the diameter of the expansion plug is equal to the diameter of the drill bit.
Screw selection: the diameter of the screw is 2-4mm smaller than that of the expansion pipe, and the length is equal to that of the expansion pipe.
Installation: There are generally no restrictions on the types of self-tapping screws, such as countersunk head self-tapping screws, round head self-tapping screws, large flat head self-tapping screws, external hexagon self-tapping screws and double-headed screws. (Peripheral accessories: gaskets, nuts, aprons, hooks, etc. ). Avoid using quick teeth (sharp wooden screws) to avoid cutting the expansion pipe when pushing in the screws. It is suggested to install and use self-tapping screws with hardening to give full play to the best friction and achieve the best fastening effect. Secondly, after the hole is blown clean, put the expansion tube into the hole and lock the object to be fixed with appropriate pointed tail screws. Plastic expansion tube should not be used too hard and should not be used many times.
Note: Attached drawing (schematic diagram of expansion pipe specification and example of adapter screw specification)