| 
 鋼管公稱壁厚/mm  | 
 每米彎曲度mm/m  | 
| 
 ≤15  | 
 ≤1.50  | 
| 
 >15~30  | 
 ≤2.0  | 
| 
 >30或D≥351  | 
 ≤3.0  | 
無縫鋼管的全長(zhǎng)彎曲度應(yīng)不大于鋼管總長(zhǎng)的1.5‰,且全長(zhǎng)彎曲度應(yīng)不大于
5.端頭外形
鋼管兩端端面應(yīng)與鋼管軸線切直,切口毛刺應(yīng)予清除。鋼管的端部切斜應(yīng)符合如下規(guī)定:
a)公稱外徑不大于
b)公稱外徑大于
技術(shù)要求
1.鋼的熔煉成分應(yīng)符合下表的規(guī)定shqcgps.com
| 
 牌號(hào)  | 
 C  | 
 Si  | 
 Mn  | 
 P  | 
 S  | 
 Cr  | 
 Ni  | 
 Cu  | 
| 
 10  | 
 0.07~0.13  | 
 0.17~0.37  | 
 0.35~0.65  | 
 ≤0.035  | 
 ≤0.035  | 
 ≤0.15  | 
 ≤0.30  | 
 ≤0.25  | 
| 
 20  | 
 0.17~0.23  | 
 0.17~0.37  | 
 0.35~0.65  | 
 ≤0.035  | 
 ≤0.035  | 
 ≤0.25  | 
 ≤0.30  | 
 ≤0.25  |