Ordinary bolts shall meet the following requirements when used as permanent connecting bolts:
1. For general bolt connections, flat washers should be placed under the bolt heads and nuts to increase the pressure bearing area.
2. Flat washers should be placed on the bolt head and nut side respectively. Generally, there should be no more than two flat washers on the bolt head side, and no more than one flat washer should be placed on the nut side.
3. For bolts and anchor bolts that are designed to require anti-loosening, nuts or spring washers with anti-loosening devices should be used, and the spring washers must be set on one side of the nut.
4. For bolt connections that bear dynamic loads or important parts, spring washers should be placed according to design requirements, and spring washers must be set on one side of the nut.
5. For I-beam and channel steel type steels, inclined washers should be used when connecting with inclined planes, so that the bearing surface of the nut and bolt head is perpendicular to the screw.
Bolt assembly:
1. Before assembling, visually inspect the bolts, nuts or the threaded holes of the connected parts. There should be no bumps or scratches, and they should comply with the drawings or the standards quoted in this code.
2. During the assembly process, do not scratch the threaded part of the bolt.
3. The head of the bolt and the washer on the end face of the nut should be in uniform contact with the plane of the fastened parts, and should not be inclined, nor should the two planes be contacted by hammering, and the screw should not bend or deform.
4. The connected parts should be evenly pressed, fit closely to each other, and be firmly connected.
5. It is strictly forbidden to use inappropriate wrenches when tightening bolts and nuts.
6. When assembling bolts and screws, screw in more than 2 to 3 pitches by hand, and then tighten them with a wrench or electric tool.
7. When assembling bolts and nuts, pay attention to protect the paint film, coating of the connected parts and the heads of bolts and nuts, so that they cannot be damaged.
8. After the nut is tightened, the head of the bolt should be exposed for 2 to 3 pitches from the end face of the nut. Both the nut and the washer face the connected body with the reverse side (the side marked with the nut is the front side, and the smooth side of the washer is the front side).
9. After the bolts are tightened, paint the mark. The mark position is generally red painted on the contact point between the bolt and the nut. The color can be changed according to different places of use, but the color must be clearly distinguished.
