From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
List of experimental plugs for testing, detailing their specific types and characteristics.
Identifier | ExFiles\Box 58\2\ Scan182 | |
Date | 1st April 1935 | |
EXPERIMENTAL PLUGS FOR TEST. Type 864 - Similar to 744 but with thin platinum central electrode. " 868 - Ramp head plug for comparison. " 871 - Increased thickness of copper sleeve. Otherwise identical with 744. " 872 - Exposed electrode head otherwise similar to 744. " 874 - Exposed electrode head Thin Platinum earth electrodes. " 877 - Wst. design for high heat conductivity. Features high internal leak path. Copper bush next to mica. Increased thickness of copper sleeve. Reduced thickness between gland nut gasket and main gasket. " 879 - Similar to 868 but with thin platinum earth electrodes. " 744B(A) - Branded "A" on gland nut. Cones only in R.R.56 metal. " 744B(B) - Branded "B" on gland nut. Gland nut only in R.R.56. " 744B(C) - Branded "C" on gland nut. Cones and gland nut in R.R.56. | ||