Bolt tightening apparatus

• US 3,917,224 A
• Filed: 04/30/1974
• Issued: 11/04/1975
• Est. Priority Date: 02/18/1974
• Status: Expired due to Term

• Current Assignee: Fred Stansfield, Michael James Roe
• Original Assignee: Fred Stansfield, Michael James Roe
• Inventors: Stansfield, Fred, Roe, Michael James
• Primary Examiner(s): Smith, Al Lawrence
• Assistant Examiner(s): Watson, Robert C.
• Application Number:
  US05/465,531
• Time in Patent Office: 553 Days
• Field of Search: 254/29A 29/452 81/57.38
• US Class Current: 254/29.00A
• CPC Class Codes: B25B 29/02 Bolt tensioners

Abstract

A apparatus for pre-tensioning a series of screwthreaded fasteners by means of apparatus including a yoke member adapted to be supported midway of its length above a single fastener by way of a single hydraulic piston and cylinder arrangement, the opposite ends of said yoke member being adapted to apply pretensioning forces to the pair of fasteners flanking said single fastener by way of adaptors applied to said pair of fasteners.

Claims

1. Apparatus for tensioning a plurality of screwthreaded fasteners, wherein the improvement comprises:

a. pairs of screwthreaded fasteners disposed in flanking relation to respective intermediary fasteners;

b. first means coacting with each one of said flanking fasteners for applying a tensile force to each flanking fastener;

c. a plurality of yoke members coacting with said first means and supported above said intermediary fasteners to exert tensile forces on pairs of fasteners flanking said intermediary fasteners;

d. second means for maintaining said yoke members in such coacting relation with said first means;

e. abutment means overlying respective intermediary fasteners and disposed to support said yoke members above said intermediary fasteners; and

f. third means coacting with said yoke members and with said abutments and creating forces in said yoke members that coact with said first means and thereby exert tensile forces in said flanking fasteners.

2. Apparatus for tensioning a plurality of screwthreaded fasteners, wherein the improvement comprises:

a. pairs of screwthreaded fasteners disposed in flanking relation to intermediary fasteners;

b. an adaptor threaded onto each flanking fastener;

c. a plurality of yoke members coacting with the adapters threaded onto the respective pairs of flanking fasteners to exert tensile forces on said pairs of flanking fasteners;

d. means securing said yoke members in such coacting relation;

e. abutment means overlying said intermediary fasteners and disposed to support said plurality of yoke members above said intermediary fasteners;

f. respective hydraulic piston and cylinder arrangements coacting with said yoke members and with respective abutment means and creating forces in said yoke members that exert tensile forces in said flanking fasteners; and

g. means for actuating said hydraulic piston and cylinder arrangements for applying equal tensile forces in said falnking fasteners.

3. The invention of claim 1 including:

a. means for exerting equal forces on said yoke members so that all flanking fasteners receive equal tensioning forces.