Grid rod processing site-Grid accessories manufacturer Jiangsu Huahai Steel Structure Co., Ltd. The grid rods are mainly composed of steel pipes, cones (sealing plates), sleeves, high-strength bolts and pins, as shown in the following figure:

Grid rod processing process

Rules for the production process of rods:


Tube blanking
1. The rod steel pipes are high-frequency welded pipes or seamless steel pipes.
2. The cutting of steel pipe adopts automatic pipe cutting machine, and the cutting groove is formed at one time.

Vertebral head making
1. The cone head material is 45#, the raw material is mainly round steel, and the cutting is cut by a sawing machine.
2. Cone head forging adopts high-speed steam punch. Or hydraulic press + special molding die.
3. The cone head is formed by machining, and the processed cone head.

Rod assembly
1. The rod assembly and welding are carried out on special equipment, using CO2 gas shielded automatic welding.
2. When welding, keep the offset between the welding torch and the rod by 5~10mm; at the same time, the welding torch and the steel tube rotate at an angle of 10~15°C; the deflection angle is opposite to the direction of rotation of the steel tube.

Rod inspection
1. Inspect whether the external dimensions of the rods after inspection meet the requirements of the design drawings.
2. The surface of the weld metal has a uniform welding wave, no cracks, crater cracks, arc scratches, weld bumps, surface slag inclusions, surface pores and other defects. There should be no spatter in the welding area; the undercut depth should be less than 0.05t (t is Tube wall thickness). At the same time, UT inspection is performed on the weld.

Rod identification
1. Check if the markings of the rods are complete.
2. The stamps of the rod parts include: rod part number, welder number, ultrasonic inspection number and other steel stamps, and the handwriting is clear and legible.

Derusting of rods
The rust removal level must reach the Sa2.5 level required by the design.

The rods are especially painted
1. The surface paint of the rods is mainly sprayed.
2. The coating thickness is controlled by a dry and wet film thickness gauge and meets the design requirements.

Rod packing and shipping
1. The rods are bundled and tied up tightly.
2. The name of the project where the rods are located, the number and number of the rods, etc. are hung on each bale.

The most commonly used rod specifications in grid calculations: φ42x3.5 φ48x3.5 φ60x3.5 φ75.5x3.75 φ89x4.0 φ114x4.0 φ140x4.5 φ159x5.0 (6, 7, 8) φ180x8.0 (10 ) Φ219x10.0 (12, 14)