The size of the welded steel pipe

The size of the welded steel pipe, the weight per unit length, to allow deviation

 

 

Structure with the size of the fine grain structural steel welded round steel pipe, the weight per unit length, allowable deviation size DIN2458 welded steel pipe size, weight per unit length "apply to the outside diameter and wall thickness of the steel pipe. Table 1 apply to the length of the tubes types. Size allowable deviation 1) pipe diameter da allow deviation: da 200mm, ± 1% (allow ± 0.5mm); 200mm ≤ da <1000mm, ± the (0.005da +1) mm; da ≥ 1000mm, ± 6mm. 2) The allowable deviation of the pipe wall thickness s: s> 10mm-0.50mm, the ceiling under the weight deviation allowed. 3) Pipe length tolerances shall comply with the requirements in Table 1.

 

 

Table 1 length types of length to allow deviation (mm) length 1) Length ± 500 exact length ≤ 6m +10 0> 6 ~ 12m +15 0> 12m

 

 

   According to the agreement

 

   1) production length delivery. This length depends on the diameter, wall thickness, and the plant should be agreed in the order. The shape allows deviation (1) to roundness pipe should be as round. The roundness scale deviation should not be greater than 2%. When steel pipe da / s> 100, it can not guarantee that this value. The Roundness R deviation is calculated according to formula (1).

 

 (1) DA minimum respectively maximum and da is the maximum outer diameter and the smallest outer diameter of the same cross-section measurements.

 

(2) Flatness visually examined steel pipe should be straight. Maximum flatness deviation 0.002L (L is the length of pipe) increased allowable weld weld increased Δa and wall thickness s relationship, shall meet the following requirements.

 

(1) Fusion welding pipe S ≤ 8mm: Δa of ≤ 2.5mm; 8mm <s ≤ 14mm: Δa of ≤ 3.0mm; 14mm <s ≤ 40mm: Δa of ≤ 4.0mm. (2) pressure welded steel pipe upsetting roughing, weld increased shall not exceed 0.3mm +0.05 s. The pipe ends of the pipe end cutting edge should be perpendicular to the pipe axis. Generally do not remove burrs.