Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Comparison table of silent tappet systems, considering spring loads only.

Identifier  ExFiles\Box 17\6\  Scan156
Date  25th September 1933 guessed
  
COMPARISON OF SILENT TAPPET SYSTEMS

SPRING LOADS ONLY CONSIDERED. (NOTE: CADILLAC SPRING LOAD TAKEN SAME AS J.3.)

CADILLAC (ECCENTRIC RATIO 1.47:1)
J.IIIX. (ECCENTRIC RATIO 1.267:1)
PHANTOM II DIRECT ACTING SCHEME.

DIA. OF PLUNGER. | 0.6234" | 0.5245" | 0.4995"
CLEARANCE BETWEEN PLUNGER & CASING. | 0.0016" | 0.00075" (0.0016) | 0.0005" (0.0016)
CROSS SECTIONAL -A CLEARANCE. AREA SQ. INS. | 0.00313 | 0.00120 | 0.00079
EFFECTIVE LENGTH OF PLUNGER -L | 0.932" | 0.650" | 0.545"
MAX. LOAD ON PLUNGER. LBS. | 58.8 | 33.45 | 149.0
MAX. PRESSURE OF OIL BENEATH PLUNGER - P - LBS/SQ.IN. | 192.8 | 155.0 | 760.0
(MAX.) LEAKAGE FACTOR - PA{Mr Paterson}/L | 0.647 | 0.286 (0.61) | 1.103 (3.53)

Pencil figures-assume that we work to the same manufacturing limits as Cadillacs instead of to an impractical clearance.
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙