鋼管種類
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外徑(D)
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鋼管壁厚(S)
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||
冷拔管
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鋼管外徑(mm)
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允許偏差(mm)
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鋼管壁厚(mm)
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允許偏差(mm)
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>30~50
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±0.3
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≤30
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±10%
|
|
>50~219
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±0.8%
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|||
熱軋管
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>219
|
±1.0%
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>20
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±10%
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標(biāo)準(zhǔn)
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牌號(hào)
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抗拉強(qiáng)度(MPa)
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屈服強(qiáng)度(MPa)
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伸長率(%)
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GB/T5312
|
320
|
320~410
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≥195
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≥25
|
360
|
360~480
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≥215
|
≥24
|
|
410
|
410~530
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≥235
|
≥22
|
|
460
|
460~580
|
≥265
|
≥21
|
|
490
|
490~610
|
≥285
|
≥21
|
標(biāo)準(zhǔn)
|
牌號(hào)
|
化學(xué)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
|