# US 4,394,879 A · Method of repairing damaged keyway

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- Number: US 4,394,879 A
- Document ID: US4394879A
- Status: Granted
- Kind: A
- Application number: 06/271,678
- Filed: 1981-06-08
- Granted: 1983-07-26
- Earliest claimed: 1981-06-08
- Inventors: William A. Reynolds
- Web page: https://patentgrep.com/patent/US4394879A

## CPC

- B22D 19/06: for manufacturing or repairing tools
- B22D 23/00: Casting processes not provided for in groups B22D1/00 - B22D21/00 (making metallic powder by casting B22F9/08; alumino-thermic welding B23K23/00; remelting metals C22B9/16)
- Y10T 29/49746: by applying fluent material, e.g., coating, casting
- Y10T 29/4981: Utilizing transitory attached element or associated separate material
- B22D: CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES (shaping of plastics or substances in a plastic state B29C; metallurgical processing, selection of substances to be added to metal C21, C22)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A simple, cost effective method is provided for repairing damaged and misshapen keyways in shafts and like parts. An insert formed of carbon or other nonmetallic material which retains its shape when subjected to welding temperatures and which will not bond to weld material is provided having length and width dimensions corresponding to the final desired configuration of the restored keyway. The insert is then placed into the damaged keyway and the free space between the defining walls of the damaged keyway and the insert is filled with weld material. Excess weld and insert material above the surface of the shaft adjacent to the keyway is next machined to present a smooth, finished surface. The final step of the method involves removal of the insert from the keyway by striking the shaft or like part against an appropriate surface in order to dislodge the insert. This method effects the repair of damaged keyways without special equipment or the need for skilled workmen. The method also allows for the repair of damaged keyways in parts which heretofore could not be economically restored.

## Claims

### Claim 1

A method of repairing a deformed or damaged keyway in a shaft or the like to provide a finished keyway having desired length and width dimensions, comprising the steps of:
providing an insert having length and width dimensions corresponding to the dimensions of the desired finished keyway;
placing said insert into the damaged keyway;
filling the free space between the defining walls of the damaged keyway and said insert with metallic weld material; and
removing said insert.

### Claim 2 (depends on 1)

A method as set forth in claim 1, wherein the insert is nonmetallic.

### Claim 3 (depends on 2)

A method as set forth in claim 2, wherein the insert is formed of carbon.

### Claim 4 (depends on 1)

A method as set forth in claim 1, including the steps of:
securing said insert by placing a small bead of weld material alonside the insert; and
thereafter filling the free space between the defining walls of the damaged keyway and said insert with metallic weld material.

### Claim 5 (depends on 1)

A method as set forth in claim 1, including the step of removing said insert from said keyway by striking the shaft or the like receiving said insert.

### Claim 6 (depends on 1)

A method as set forth in claim 1, including the steps of:
applying excess metallic weld material about said insert, adjacent to said keyway and above the normal surface of said shaft or the like;
machining said excess weld material and any portion of said insert extending above said normal surface of the shaft or the like; and
thereafter removing said insert.