Steel manufacturing precision engineering and manufacturing items intent (ie promised error) in the "war construction and inspection standards and other related standards have made ​​specific rules, this section will not repeat, but we have to pay attention to some of the manufacturing process for manufacturing precision about the demand impacts.

1 loft, number of materials and cut

(1) Loft crossed should understand symbols indicating device, screw symbols, strengthening the position of the direction board skew symbol, the other with symbols and centerline baseline and testing lines, if necessary, to manufacture the model.

(2) pay attention reserved for manufacturing, welding apparatus of shortening; cutting, planing and milling allowance; unit reserved scale demand; members under bagging material scales.

(3) Before marking, materials, twists or other deformations should be corrected. Elected correct flame, the heating temperature should be selected based on the performance of steel, but not exceeding 900cc. Low-alloy structural steel after heating correction should be cooled slowly.

2 Hole

(1) When the hole punching processing methods were adopted, the control panel should be no greater than the thickness of 12mm, after punching holes around the use of flat grinding wheel.

(2) identify the group of bolt holes [intended to monitor the necessary accuracy). All bolt holes node interface board and a member connected as a group. Butt joints in the side of the splice bar for a group of bolt holes. Bolt holes or joints between two adjacent nodes as a group. By the convergence of flexural members flange bolt holes on the bolt holes per meter length range as a group.
 
(3) monitor the volume of the accumulation error: Because steel assembly line, often mass-produce the same error, and this error is within the "construction and inspection standards" in the promise of errors. For example, more than 3m in length adjacent beams agreed between the two groups end hole spacing for the soil 3mm. If a mistake to focus on the direction of the maximum, the device accuracy and progress of the trouble, especially high-rise buildings concentrated negative Gongyi beam.