Various 7 ¼” Gauge
“Standards”
|
|
|
|
|
|
|
|
|
Nominal Track Gauge 7 1/4" |
Tolerances |
SMEE |
Baker |
Baker (N) |
Derby |
Evans |
|
|
|
|
|
|
|
|
|
Given dimensions for track |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Track Gauge * |
minimum |
7.250 |
7.25 |
7.25 |
|
7.250 |
|
Track Gauge * |
maximum |
n/s |
7.38 |
7.38 |
|
n/s |
|
Track back to back * |
maximum |
6.710 |
6.70 |
6.70 |
|
6.710 |
|
Rail head radius |
n/c |
n/s |
0.10 |
0.10 |
|
n/s |
|
Rail Head Width (Nominal) |
|
0.50 |
|
|
|
|
|
Given dimensions for wheel sets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Check Gauge |
+/- 0.015" |
|
6.95 |
6.95 |
|
|
|
|
|
|
|
|
|
|
|
Root radius |
n/c |
0.100 |
0.12 |
0.12 |
|
0.100 |
|
Flange thickness |
n/c |
0.154 |
0.14 |
0.19 |
|
0.154 |
|
Flange tip radius *** |
n/c |
0.065 |
0.06 |
0.08 |
|
0.065 |
|
Wheel ( tyre ) width * |
minimum |
|
0.80 |
|
|
|
|
|
n/c |
|
|
1.12 |
|
|
|
Wheel edge chamfer height |
n/c |
0.040 |
0.04 |
0.06 |
|
0.040 |
|
Chamfer angle ( degrees ) |
n/c |
45 |
45 |
45 |
|
45 |
|
Flange angle ( degrees ) ** |
n/c |
20 |
20 |
20 |
|
20 |
|
Coning angle ( degrees ) ** |
n/c |
2 |
3 |
3 |
|
2 |
|
|
|
|
|
|
|
|
|
Computed dimensions for wheel sets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Diameter Point Width |
n/c |
|
0.25 |
0.30 |
|
|
|
Wheel set Gauge |
n/c |
|
7.08 |
7.11 |
|
|
|
Wheel set back to back * |
n/c |
|
6.80 |
|
|
|
|
|
minimum |
|
|
6.75 |
|
|
|
Flange depth |
n/c |
|
0.18 |
0.25 |
|
|