表1 化学成分及头部标记
头部标记 | 螺栓类型 | 成分% | |||
碳 | 锰 | 磷 | 硫 | ||
T-0 | 0 | 0.55 max |
| 0.048 max | 0.058 max |
T-1 | 1 | 0.28~0.55 | 0.60 min | 0.048 max | 0.058 max |
T-3 | 3 |
|
|
| 见表2 |
表2 3型重型六角结构螺栓的化学成分要求
化学元素 | 成份 % | ||||||
等级 | |||||||
A | B | C | D | E | F | ||
碳 C | 熔炼分析 | 0.33~0.40 | 0.38~0.48 | 0.15~0.25 | 0.15~0.25 | 0.20~0.25 | 0.20~0.25 |
产品分析 | 0.31~0.42 | 0.36~0.50 | 0.14~0.26 | 0.14~0.26 | 0.18~0.27 | 0.19~0.26 | |
锰 Mn | 熔炼分析 | 0.90~1.20 | 0.70~0.90 | 0.80~1.35 | 0.40~1.20 | 0.60~1.00 | 0.90~1.20 |
产品分析 | 0.86~1.24 | 0.67~0.93 | 0.76~1.39 | 0.36~1.24 | 0.56~1.04 | 0.86~1.24 | |
磷 P | 熔炼分析 | 0.035 max | 0.06~0.125 | 0.035 max | 0.035 max | 0.035 max | 0.035 max |
产品分析 | 0.040 max | 0.06~1.25 | 0.040 max | 0.040 max | 0.040 max | 0.040 max | |
硫 S | 熔炼分析 | 0.040 max | 0.040 max | 0.040 max | 0.040 max | 0.040 max | 0.040 max |
产品分析 | 0.045 max | 0.045 max | 0.045 max | 0.045 max | 0.045 max | 0.045 max | |
硅 Si | 熔炼分析 | 0.15~0.35 | 0.30~0.50 | 0.15~0.35 | 0.25~0.50 | 0.15~0.35 | 0.15~0.35 |
产品分析 | 0.13~0.37 | 0.25~0.55 | 0.13~0.37 | 0.20~0.55 | 0.13~0.37 | 0.13~0.37 | |
铜 Cu | 熔炼分析 | 0.25~0.45 | 0.20~0.40 | 0.20~0.50 | 0.30~0.50 | 0.30~0.60 | 0.20~0.40 |
产品分析 | 0.22~0.48 | 0.17~0.43 | 0.17~0.53 | 0.27~0.53 | 0.27~0.63 | 0.17~0.43 | |
镍 Ni | 熔炼分析 | 0.25~0.45 | 0.50~0.80 | 0.25~0.50 | 0.50~0.80 | 0.30~0.60 | 0.20~0.40 |
产品分析 | 0.22~0.48 | 0.47~0.83 | 0.22~0.53 | 0.47~0.83 | 0.27~0.63 | 0.17~0.43 | |
铬 Cr | 熔炼分析 | 0.45~0.65 | 0.50~0.75 | 0.30~0.50 | 0.50~1.00 | 0.60~0.90 | 0.45~0.65 |
产品分析 | 0.42~0.68 | 0.47~0.83 | 0.27~0.53 | 0.45~1.05 | 0.55~0.95 | 0.42~0.68 | |
钒 V | 熔炼分析 | ① | ① | 0.020 min | ① | ① | ① |
产品分析 | ① | ① | 0.010 min | ① | ① | ① | |
钼 Mo | 熔炼分析 | ① | 0.06 max | ① | 0.10 max | ① | ① |
产品分析 | ① | 0.07 max | ① | 0.11 max | ① | ① | |
钛 Ti | 熔炼分析 | ① | ① | ① | 0.05 max | ① | ① |
产品分析 | ① | ① | ① | 0.06 max | ① | ① | |
①这些元素没有指定或要求。 |
表3 抗拉强度A
公称直径(in) | 最小拉力载荷(lbf) | |
Type 0 B | Type 1和3 C | |
1/2 | 10500 | 17050 |
5/8 | 16700 | 27100 |
3/4 | 24700 | 40100 |
7/8 | 34200 | 55450 |
1 | 44850 | 72700 |
A. 螺纹应力截面积计算公式:AS = 0.7854 [ D -(0.9743/N)]2,D=公称直径,N=每英寸螺纹牙数。 B. Based on 74 000 psi unit tensile strength. C. Based on 120 000 psi unit tensile strength. |
螺栓太短,无法进行全尺寸测试或由于其他原因未进行拉力测试,应符合以下硬度:
Type 0 —— Rockwell B:80~100
Type 1 和3 —— Rockwell C:25~34
在原始询价和订单中有规定的情况下,螺栓应按照原件中11.2进行抗剪强度试验,并应满足表4的要求。(无螺纹螺栓体长度小于螺栓公称直径两倍的螺栓,买卖双方就试验方法和抗剪强度值达成一致后,才能进行抗剪强度试验。)
表4 抗剪强度
公称直径(in) | 最小负载(lbf) | |||
Type 0 | Type 1 和3 | |||
Single Shear Strength Through Threads A | Single Shear Strength Through BodyB | Single Shear Strength Through Threads C | Single Shear Strength Through BodyD | |
1/2 | 6950 | 9000 | 9350 | 14600 |
5/8 | 11150 | 14100 | 15050 | 22850 |
3/4 | 16650 | 20250 | 22450 | 32850 |
7/8 | 23150 | 27600 | 31150 | 44750 |
1 | 30400 | 36050 | 41000 | 58450 |
A. Based on 55 200 psi unit shear strength across the area at root of threads. B. Based on 45 880 psi unit shear strength across the nominal area. C. Based on 74 400 psi unit shear strength across the area at root of threads. D. Based on 74 400 psi unit shear strength across the nominal area. |