The yoke & bolt manway provides the most economical pressure vessel access. As a self-energizing unit, yoke & bolt manways require positive internal pressures of at least 50 psi to achieve a seal. The standard yoke & bolt unit consists of a reinforcing ring, a pressed cover, one or two yokes (depending on type) with bolts and a gasket. Rings and covers are available in carbon steel or stainless steel.
Standard yoke & bolt manway dimensions and ratings.
| Nom Size | Cover Thickness (in.) | Pressure Rating (psi) | Yokes | Approx. Weight (lbs.) | |||||
| Carbon Steel | Stainless Steel | Carbon Steel | Carbon Steel 1/16 corrosion allowance | Stainless Steel to 300F | Number | Size (in.) | Bolt | ||
| 4 X 6 | 3/8 | 3/8 | 1000 | 694 | 833 | 1 | 5-1/2 X 2-1/4 | 3/4 | 6 |
| 6 X 8 | 7/16 | 3/8 | 825 | 606 | 505 | 1 | 8-1/2 X 3-1/2 | 3/4 | 11 |
| 11 X 15 | 1/4 | 1/4 | 300 | 168 | 250 | 2 | 12 X 3-1/2 | 3/4 | 25 |
| 11 X 15 | 1/2 | 7/16 | 600 | 459 | 382 | 2 | 12 X 3-1/2 | 3/4 | 40 |
| 12 X 16 | 1/4 | 1/4 | 300 | 168 | 250 | 2 | 12 X 3-1/2 | 3/4 | 26 |
| 12 X 16 | 1/2 | 7/16 | 600 | 459 | 382 | 2 | 12 X 3-1/2 | 1 | 43 |
| 12 X 16 | 7/8 | ------- | 1000 | 862 | ------- | 2 | 12 X 3-1/2 | 3/4 | 76 |
| 14 X 18 | 5/16 | ------- | 300 | 192 | ------- | 2 | 15 X 6 | 1 | 46 |
| 18 X 24 | 5/8 | 1/2 | 200 | 162 | 106 | 2 | 18 X 3 | 1 | 108 |