Over the years, due to the simple production technology and low market access threshold for screws, nuts and b···
Over the years, due to the simple production technology and low market access threshold for screws, nuts and bolts, the bolt factory has fallen into low-level competition, the market is not in line with national quality standards filled with low-quality special screws, ordinary people in the market is difficult to distinguish between the Good and bad. Among them, inferior products in the furniture due to the shallow sets of wire, it is easy to move off in the process. There are some non-standard screws used in the pipeline because the rust-proof treatment is not off, a short time will be macerated, the phenomenon of water leakage. Then there are shoddy expansion screws used on the chandelier is more dangerous, once the lack of load-bearing strength is likely to cause heavy objects down the injury accident.
How can that be purchased to quality special screws?
1, measuring the outer diameter, the inferior product, and thin and short, obviously qualified screws than the national standard circle of thin. More surprisingly, the inferior product is not even on the screw spring gasket. Spring gasket main role of pressure, the lack of spring gasket expansion screws, it is not easy to fix firmly.
2, look at the appearance, genuine screws after surface treatment, high gloss, no blistering smooth interface. And low-quality screws are rough, shallow threads, more burrs, screw angle width varies, the thread groove is too shallow, uneven threads, so that the Poor-quality screws, if used on the furniture, it is easy to slip wire or even break, basically "disposable products".