Drawworks gearbox with redundant braking on input side

Abstract

A drawworks gearbox includes additional braking on the input side of the gearbox to provide a redundant emergency brake and, optionally, a separate parking brake with the drum-side brakes being the emergency brake. An air-cooled brake disc is attached to a high speed coupling connected to the gearbox input pinion. A hydraulic-apply, spring-release brake is mounted to the gearbox housing at each pinion location and arranged to act on its respective disc.

Claims

1. A drawworks brake system comprising: at least one set of emergency and parking brakes located on each side of a drawworks drum, the at least one set of emergency and parking brakes including a brake disc acted upon by a drum brake; at least one set of redundant brakes located on an input side of a drawworks gearbox, the at least one set of redundant brakes including: an air-cooled disc attached to a high speed coupling connected to an input pinion of the drawworks gearbox; a brake mounted to a housing of the drawworks gearbox and arranged to engage the air-cooled disc.

2. A drawworks brake system according to claim 1 wherein the at least one set of redundant brake is a hydraulic-apply, spring-release brake.

3. A drawworks brake system according to claim 1 wherein the at least one set of redundant brakes is deployed as an emergency brake.

4. A drawworks brake system according to claim 1 wherein the at least one set of redundant brakes is deployed as a parking brake.

5. A drawworks brake system according to claim 1, wherein the at least one set of emergency and parking brakes is a failsafe emergency brake.

6. A drawworks brake system according to claim 1, wherein the drum brake comprises a non-cyclical, limited duty, dynamic brake.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an isometric view of a preferred embodiment of a drawworks gearbox with a braking system on the input side of the gearbox.

(2) FIG. 2 is an enlarged view of a preferred embodiment of the hydraulic-apply, spring-release brake of FIG. 1 taken along section circle 2 of FIG. 1.

(3) FIG. 3 is an isometric view of the brake of FIG. 2.

(4) FIG. 4 is another isometric view of the brake of FIG. 2.

(5) FIG. 5 is a front elevation view of FIG. 1.

ELEMENTS AND NUMBERING USED IN THE DRAWINGS AND DETAILED DESCRIPTION

(6) 10 Drawworks 11 Drum 13 Gearbox 15 Motor 17 Brake disc 19 Drum side brake (spring applied, hydraulic release) 21 Input side of 13 23 High speed coupler 25 Input pinion 27 Housing 29 Flange 30 Additional or redundant braking system 31 Air-cooled brake disc 33 Gearbox input side brake (hydraulic applied, spring release)

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) Referring to the drawings, a drawworks 10 is made up of a drum 11 connected to a gearbox 13 and motor 15. On each side of the drum 11 is a brake disc 17 acted upon by a brake 19 such as a caliper with brake pads. The discs 17 and their brakes 19 act as the emergency and parking brake, with the motor 15 providing the primary brake.

(8) Located on the input side 21 of the gearbox 13 is a preferred embodiment of an additional or redundant braking system 30. An air-cooled brake disc 31 is attached to a high speed coupling 23 connected to the gearbox input pinion 25. A hydraulic-apply, spring-release brake 33 is mounted to the gearbox housing 27 at a pinion 25 location. For example, a pad or flange 29 can serve as the mounting point for the brake 33 on the gearbox 13, with the brake 33 arranged to act on its respective disc 31. The braking system 30 may be integrated into the drawworks control system (not shown), including an automatic brake monitoring system of a kind known in the art.

(9) Preferably, there is one set of brakes 30 at each pinion 25 location. The input-side brakes 30 preferably have a 200% capacity, meaning that when used together the brakes 30 can support the rated load of the drawworks completely independent of the motor 15 or drum-side braking system 17, 19. A BSAB 90 DUAL-ACTION brake (Svendborg Brakes ApS) or its equivalent is a suitable brake 33.

(10) The preferred embodiments described here provide examples of a drawworks gearbox with redundant braking on the input side of the gearbox. The following claims define the scope of the invention and include the full range of equivalents to the recited elements.