BR Standard Washout Plugs
To facilitate the inspection and cleaning of boilers at regular intervals most designs of boiler incorporate several washout plugs, the number and location of the plugs will vary with the boiler design. These are machined from LG4 Gun Metal, with one end having a tapered thread to engage in a matching thread in the boiler shell and at the other end a raised head.
British Rail Standard Washout Plugs for Locomotive use. These BR Standard Washout Plugs are available in a range of sizes machined from LG4 Gun Metal
| Thread | Centre Section | Square | Size No. | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Plug Type | OD Small End | TPI | Taper Inc | Length | Dia. | Length | AF | M/F | Length | Small to Large |
| BR Std | 1⅜" to 2" by 1/16" | 12 | 1:08 | 1⅝" | - | - | 1¼" | M | 1" | 1 to 11 |
| GWR | 1 5/16" to 1 9/16" by 1/16" | 12 | 1:08 | 1½" | - | - | 1" | M | 1" | 1 to 5 |
| LMS | 1 7/16" to 2" by 1/16' | 12 | 1:12 | 1½" | - | - | 1¼" | M | 1" | A to K |
| LNER XL | 1⅜" to 1¾" by ⅛" | 11 | 1:09 | 2¾" | 1⅝" | 1½" | 1¼" | M | 1½" | 1 to 4 |
| LNER Long | 1⅜" to 1¾" by ⅛" | 11 | 1:09 | 2" | 1⅝" | ⅞" | 1¼" | M | 1½" | 1 to 4" |
| LNER Ordinary | 1⅜" to 2" by ⅛" | 11 | 1:09 | 2" | - | - | 1¼" | M | 1½" | 1 to 6" |
| SR Long | 1⅜" to 2¼" by 1/16" | 12 | 1:08 | 1⅝" | Tapered | 1⅝" | 1¼" | M | 1" | - |
| SR Short | 1⅜" to 2¼" by 1/16" | 12 | 1:08 | 1⅝" | - | - | 1¼" | M | 1" | - |
| Austerity | 1 7/16" to 1¾" by 1/16" | 12 | 1:12 | 1½ | - | - | 1 3/16" | M | 1" | A - F |
| BSPT | 1", 1⅛", 1¼", 1½", 1¾" Nominal | 11 | 1:16 | 1⅝" | - | - | 1¼" | M | 1" | - |
