What is the difference between bolts and screws?

　The difference between bolts and screws depends on two levels: one is the appearance level, part of the studs of the bolts are strictly managed as cylindrical to install nuts, but part of the studs of the screws are sometimes conical and even better; on the other hand, the application is used, the other half of the screws are the overall target raw material rather than the nut. In many application sites, bolts are also independently working and are immediately screwed into the hole where the threads were drilled in advance. There is no need for nuts to cooperate with each other. At this time, the bolts are functionally summarized into screws.

　　The categories of bolts are quite diverse, but in most cases, they are determined by their studs and bolt heads.

　　1. The threads of the column can be divided into coarse threads. Fine threads and thread nominal diameter threads, so they are called fine bolts and thread nominal diameter bolts.

　　2. The shape and main uses of the bolt head are different and are divided into hexagon head bolts, square head bolts, semicircular head bolts, countersunk bolts, holed bolts, T-shaped head bolts, hook head (foot) bolts, etc.

　　3.Xuzhou Xinxing Dakeluo Technology Co., Ltd.The bolts are extended according to the additional expansion parts and then the bolts are sent to grow.

　　4. The bolts can be used to grow high-toughness bolts, high-precision bolts and fastening bolts according to the commonly used materials and production precision.

　　5. Bolts are divided into more than 10 levels according to performance standards, including 3.6.4.6.4.8.5.6.6.8.8.8.9.8.10.9.12.9. Among them, the bolt materials are low-carbon environmentally friendly alloy steel or low-carbon steel and have been heat treated (heat treatment. quenched). They are collectively called high-toughness bolts, and others are collectively called general bolts. The bolt performance level model consists of two parts of data, each indicating the nominal pressure compressive strength value and yield strength ratio of the bolt raw material.