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Bump test report for Woodhead 12.5% type leaf springs, detailing conditions, fracture analysis, and material properties.


Identifier  WestWitteringFiles\M\2October1924-December1924\  Scan37
Date  14th October 1924
  
BUMP TEST
Re. 40/50 FRONT SPRINGS.
TEST OF LATEST PATTERN WOODHEAD 12.5% TYPE SPRINGS (F71790/1/2).
CONDITIONS: 2" CAMS SET AT 180°. DRUM MAKES 105 RPM. TYRES AT 65 LBS/SQ".
LOAD ON FRONT OF CHASSIS = 1000LBS.

TABLE DATA:
COLUMN HEADERS: DETAILS OF SPRING, FRACTURE, POSITION OF LEAF, POSITION OF FRACTURE FROM CENTRE BOLT, APPROXIMATE RUNNING TIME (HRS MINS), THICKNESS OF LEAF, BRINELL AT FRACTURE.

ROW 1:
DETAILS OF SPRING: No.005. NEAR-SIDE., F71790., 1100 LBS. FLEXION: COMPRESSION = 1.6", REBOUND = 2.58".
FRACTURE A: POSITION OF LEAF: BOTTOM (FIFTH). POSITION OF FRACTURE FROM CENTRE BOLT: 1.5" TO FRONT. RUNNING TIME: 13-7. THICKNESS OF LEAF: .223". BRINELL AT FRACTURE: 363.
FRACTURE B: POSITION OF LEAF: NEXT TO BOTTOM. POSITION OF FRACTURE FROM CENTRE BOLT: 1.75" TO FRONT. RUNNING TIME: 14-47. THICKNESS OF LEAF: .225". BRINELL AT FRACTURE: 375.

ROW 2:
DETAILS OF SPRING: No.006. OFF SIDE, F71792., 1200 LBS. FLEXION: COMPRESSION = 1.8", REBOUND = 2.53".
FRACTURE D: POSITION OF LEAF: BOTTOM. POSITION OF FRACTURE FROM CENTRE BOLT: 1.5" TO REAR. RUNNING TIME: 22-12. THICKNESS OF LEAF: .227". BRINELL AT FRACTURE: 388.
FRACTURE C: POSITION OF LEAF: TOP. POSITION OF FRACTURE FROM CENTRE BOLT: 2" TO REAR. RUNNING TIME: 26-17. THICKNESS OF LEAF: .285". BRINELL AT FRACTURE: 363.

ROW 3:
DETAILS OF SPRING: No.007. OFF SIDE, F71791., 1150 LBS. FLEXION: COMPRESSION = 1.9", REBOUND = 2.5".
FRACTURE E: POSITION OF LEAF: BOTTOM. POSITION OF FRACTURE FROM CENTRE BOLT: 1.5" TO FRONT. RUNNING TIME: 13-3. THICKNESS OF LEAF: .225". BRINELL AT FRACTURE: 375.
FRACTURE F: POSITION OF LEAF: TOP. POSITION OF FRACTURE FROM CENTRE BOLT: 2" TO REAR. RUNNING TIME: 19-36. THICKNESS OF LEAF: .278". BRINELL AT FRACTURE: 375.

ROW 4:
DETAILS OF SPRING: No.008. NEAR SIDE, F71790., 1100 LBS. FLEXION: COMPRESSION = 1.8", REBOUND = 2.4".
FRACTURE G: POSITION OF LEAF: BOTTOM. POSITION OF FRACTURE FROM CENTRE BOLT: 1.5" TO REAR. RUNNING TIME: 24-56. THICKNESS OF LEAF: .228". BRINELL AT FRACTURE: 375.
FRACTURE H: POSITION OF LEAF: TOP. POSITION OF FRACTURE FROM CENTRE BOLT: 1" TO FRONT. RUNNING TIME: 31-1. THICKNESS OF LEAF: .285". BRINELL AT FRACTURE: 363.
  
  
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).


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