材质 
1/4
20|28|32
0.4375
0.428
0.505
0.488
0.382
0.368
5/16
18|24|32
0.5
0.489
0.577
0.557
0.461
0.445
3/8
16|24|32
0.5625
0.551
0.65
0.628
0.509
0.491
7/16
14|20|28
0.6875
0.675
0.794
0.768
0.619
0.599
1/2
13|20|28
0.75
0.736
0.866
0.84
0.667
0.645
9/16
12|18|24
0.875
0.861
1.01
0.982
0.778
0.754
5/8
11|18|24
0.9375
0.922
1.083
1.051
0.857
0.831
3/4
10|16|20
1.125
1.088
1.299
1.24
1.015
0.985
7/8
9|14|20
1.3125
1.269
1.516
1.447
1.172
1.14
1
8|12|20
1.5
1.45
1.732
1.653
1.33
1.294
1-1/8
7|12|18
1.6875
1.631
1.949
1.859
1.52
1.48
1-1/4
7|12|18
1.875
1.812
2.165
2.066
1.71
1.666