# US 5,701,958 A · Apparatus for drilling perforations in well casings

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,701,958 A
- Document ID: US5701958A
- Status: Granted
- Kind: A
- Application number: 08/575,638
- Filed: 1995-12-20
- Granted: 1997-12-30
- Earliest claimed: 1995-12-20
- Inventors: Tom E. Braziel
- Web page: https://patentgrep.com/patent/US5701958A

## CPC

- E21B 43/112: Perforators with extendable perforating members, e.g. actuated by fluid means
- E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS

## Abstract

Apparatus for drilling perforations in a well casing to reinitiate water flow into the casing to restore operation of a well. The apparatus includes a pneumatic drill mounted within a housing which is capable of being lowered into a well casing. The drill is moveable by remote control between a rest position and a working position within the housing to cause a drill bit to pass through a port in the housing to drill perforations at selected locations in the well casing.

## Claims

### Claim 1

An apparatus for drilling perforations in well casings, comprising:
a drill assembly;
transporting means secured to the top end of the drill assembly for lowering the drill assembly down to selected locations within a well casing;
a drill mounted in the drill assembly, the drill being movable between a rest position and a working position for drilling perforations through the well casing at selected locations; and
positioning means connected to the drill assembly and extending out the top of the well casing for moving the drill between the rest position and the working position by an operator above the earth's surface, wherein the positioning means comprises cam means mounted in the housing and a cable connected to the cam means to rotate the cam to force the drill into the working position.

### Claim 2 (depends on 1)

The apparatus of claim 1 wherein the positioning means further includes means mounted in the housing for resiliently returning the drill to the rest position when tension is removed from the cable.

### Claim 3

A perforator for use in repairing a water well, comprising:
a pneumatic drill for operating a drill bit to drill perforations in a well casing;
a housing containing the drill, the housing having a port through a wall thereof to permit passage of the free end of the drill bit;
means within the housing for supporting the drill and moving the drill from a rest position to a working position, whereby the drill bit may be selectively extended through the port to drill a hole through the well casing;
means for providing compressed air to the drill from a source above the surface of the earth; and
positioning means for remotely controlling the movement of the drill between the rest position and the working position by an operator above the surface of the earth, wherein the drill supporting and moving means comprises a cam rotatably supported within the housing and in contact with the drill, and a cam handle attached to the cam and connected to the positioning means.

### Claim 4

A perforator for drilling holes in a well casing installed in a well, comprising:
a drill assembly positionable at selected depths within the well casing;
a pneumatic drill mounted in the drill assembly and moveable from a rest position to a working position within the drill assembly under remote control by an operator to drill holes at selected locations through the well casing;
a cam mechanism rotatably mounted in the drill assembly and abutting the drill; and
an actuator attached to the cam mechanism and operable from above the earth's surface to rotate the cam mechanism and move the drill from the rest position to the working position.

### Claim 5 (depends on 4)

The perforator of claim 4 further comprising a spring mounted in the drill assembly and exerting a force on the drill to return the drill to the rest position after drilling a hole in the well casing.

### Claim 6 (depends on 4)

The perforator of claim 4 wherein the cam mechanism includes a cam and a cam limiter attached thereto, the cam limiter engaging the base of the drill opposite the drill bit, whereby the cam limiter forces the drill into the working position upon rotation of the cam by the actuator.

### Claim 7 (depends on 6)

The perforator of claim 6 wherein the actuator includes a handle attached to the cam and a cable attached to the handle, the cable extending out the top of the well casing, whereby a force applied to the cable acts on the handle and rotates the cam.