Bearings – Rotary bearing – Roller drill bit
Patent
1981-10-26
1984-06-05
Footland, Lenard A.
Bearings
Rotary bearing
Roller drill bit
384130, F16C 3374
Patent
active
044525397
ABSTRACT:
The present invention relates to a drill bit (10) incorporating one or more rotary cutters (14). The rotary cutters (14) are supported for rotation by a bearing assembly including ball bearings (28) running in races (24, 26) in the rotary cutter and drill bit body (20). The bearing assembly further includes an annular bushing (34). A sealing assembly (36) including an O-ring seal (38) is provided to seal lubricant within the bearing assembly and prevent external contaminants from entering the bearing assembly. Corrosion has been found to destroy the seal surfaces (42, 44) against which the O-ring seal acts (38). It has been found that plating the sealing surfaces with a material passive to the electrochemical system or higher in the electromotive series than the material forming the sealing surfaces reduces corrosion. Alternatively, a sacrificial anode (68) is provided about the sealing surfaces to render the surfaces cathodic and resist corrosion. In another embodiment, an impressed electrical potential is provided which also renders the sealing surfaces cathodic, thereby reducing corrosion.
REFERENCES:
patent: 3484349 (1969-12-01), Vrable
patent: 3616418 (1971-10-01), Anderson et al.
patent: 3649492 (1972-03-01), Marsh et al.
patent: 3734181 (1973-05-01), Shaffer
patent: 3761145 (1973-09-01), Schumacher, Jr.
patent: 3891394 (1975-06-01), Smith et al.
patent: 3977956 (1976-08-01), Bagnulo
patent: 3990525 (1976-11-01), Penny
patent: 4098358 (1978-07-01), Klima
patent: 4194795 (1980-03-01), Rife
patent: 4200343 (1980-04-01), Highsmith
Drilling Practices Manual, "Corrosion Control in Drilling Operations", Chapter 15, pp. 381-399, by Charles C. Patton.
ASM Committee on Failures by Corrosion, "Corrosion Failures", Stress-Corrosion Cracking and Failures of Mechanical Face Seals.
Design Engineering, "Getting the Jump on Bearing Corrosion", May 1981, pp. 47-49.
Petroleum Engineer International, "Mud Pump Failure Analysis", pp. 162-178, Jul. 1981, by Edwin C. Lewis II.
Kent's Mechanical Engineers' Handbook, Twelfth Edition, pp. 3-18 and 3-19.
An Unidentified Document Defining Corrosion, p. A3-11.
Davis Randy C.
Evans Robert F.
Footland Lenard A.
Meier Harold E.
Varel Manufacturing Company
LandOfFree
Bearing seal for rotating cutter drill bit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Bearing seal for rotating cutter drill bit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bearing seal for rotating cutter drill bit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1494975