The main problem of tyre renovation is quality and safety. If the quality is too hard, there is no danger.
The quality problems mainly include: 1. The problem of the fetus itself, 2, the process of repair, 3, the poor quality of raw materials, 4, and the pressure of vulcanization temperature are unstable. All of these can lead to defective tyres.
1. Fetal problems
There are more than 5 wounds in the fetal body, the wound is more than 5CM, the tire is damaged, the curtain layer and the meridional layer are damaged. It is usually done by the operator by tapping and listening to see if a tyre can be refurbished. It can also be used to detect the fetal body with the detection machine and spark detector.
2. Fix the process
The repair process mainly includes external repair, internal repair, brushing glue, filling. Repair using wire wheel, or bowl of metal grinding head grinding wear parts, try not to hurt the buffer layer or layer, to follow the cord to grinding, polishing the tire shoulder pattern groove to burnish more than 10 mm, width is 20 mm, to increase the tread and the bonded area of the carcass and refined, the quality standard for tires should file, all the rasp, uniform grinding grain, shade thrum no more than 1 mm, do not leave any part bright slag, floating plastic wire and coke burning phenomenon. In repairing the damage according to the size of the through hole and not through hole of the cord match the patch to reinforcing layer, using the wire wheel according to the size of the patch, sand oil skin glue thicker can keep file but must be polished out new mill, actual grinding size than the patch more than 10 mm per side, with filling were the center of the patch must be with the center of the through hole or not through hole is, cannot be offset, and should be marked by the patch after patch type, easy operation, after more than half of all tire body injury body cord are the through hole, but can be a bit larger size, the final will tire rubber in vivo and in vitro to clean up into the next process to fill glue).
3. Poor quality of raw materials
The quality of tread glue directly affects the driving distance of the tire. The role of the cushion glue is to pull the tire to the body not to separate, often said the degumming, is to have the relation with the cushion glue. The friend who buys a flat tire can think for himself, spend 800 yuan to buy a 1200r-20 tire to run 50 thousand kilometers, the same model tire cost 1000 yuan can travel more than 80 thousand kilometers. Do you spend more than 200 yuan more on more than 30,000 kilometers? You want to buy cheap tires, so the manufacturers have to use cheap materials.
4. The curing temperature and pressure are unstable
This problem may not be known to many tire factories, because the equipment manufacturers supply them may not know the principle.
Vulcanization is a chemical reaction, temperature 115 degrees Celsius, error 1 degree Celsius. Pressure of inner tube is 8 kg, pack pressure of 4 kg, vulcanized tank pressure 6 kg, error 0.1-0.5 kg. When the cushion glue reaches the specified temperature, the sulfide reaction is produced, and the air in the rubber is used to discharge the rubber. On the other hand, if you don't get it or exceed it, you can't have an accurate chemical reaction, and there's air in the tire, and there's a bag.