钢管种类
|
外径(D)
|
钢管壁厚(S)
|
||
冷拔管
|
钢管外径(mm)
|
允许偏差(mm)
|
钢管壁厚(mm)
|
允许偏差(mm)
|
>30~50
|
±0.3
|
≤30
|
±10%
|
|
>50~219
|
±0.8%
|
|||
热轧管
|
>219
|
±1.0%
|
>20
|
±10%
|
标准
|
牌号
|
抗拉强度(MPa)
|
屈服强度(MPa)
|
伸长率(%)
|
GB/T5312
|
320
|
320~410
|
≥195
|
≥25
|
360
|
360~480
|
≥215
|
≥24
|
|
410
|
410~530
|
≥235
|
≥22
|
|
460
|
460~580
|
≥265
|
≥21
|
|
490
|
490~610
|
≥285
|
≥21
|
标准
|
牌号
|
化学成分(%)
|
||||
C
|
Si
|
Mn
|
P
|
S
|
||
GB/T5312
|
320
|
≤0.16
|
≤0.35
|
0.40~0.70
|
≤0.035
|
≤0.035
|
360
|
≤0.17
|
≤0.35
|
0.40~0.80
|
≤0.035
|
≤0.035
|
|
410
|
≤0.21
|
≤0.35
|
0.40~1.20
|
≤0.035
|
≤0.035
|
|
460
|
≤0.22
|
≤0.35
|
0.80~1.40
|
≤0.035
|
≤0.030
|
|
490
|
≤0.23
|
≤0.35
|
0.80~1.50
|
≤0.035
|
≤0.030
|