Advanced Mechanical Design - Mining Drill Head Gearbox Design

ADVANCED MECHANICAL DESIGN
Major Assignment
Mining Drill Head Gearbox Design
Done By:

Contents
Assignment Requirement:...........................................................................................................................3
Segments to be covered in the Assignment:...............................................................................................3
System Details:............................................................................................................................................5
Drill string:...............................................................................................................................................5
Hammer:..................................................................................................................................................6
Drill teeth:................................................................................................................................................6
Hydraulic Motor:.....................................................................................................................................6
Design Requirement:...............................................................................................................................7
Product Design Specification:......................................................................................................................7
Performance requirements:....................................................................................................................7
Operation Requirements:........................................................................................................................7
Working Environment:............................................................................................................................8
Maintenance:..........................................................................................................................................8
Gear Ratio Calculation:................................................................................................................................8

Assignment Requirement:
To design an entire Gearbox Assembly for mining drill head. The Gearbox
assembly is mounted on Drill rig mast and drives a drill string. The power to the
Gearbox is from a hydraulic motor. The motor torque and speed are controlled
with the help of the Gearbox and then allowed to transmit through the Drill string
to the Drillbit.
Segments to be covered in the Assignment:
1. Product Design Specification
2. Gear Ratio Calculation
3. Gear Box Design
4. Selection of Number of Gears
5. Design of Gears
6. Load Calculation
7. Shaft Design
8. Faster selection
9. Bearing Selection
The overall gearbox design is required, the gearbox comprises of various kinds of
gears, bearings, shafts, fasteners, etc. Initially, a detailed product design
specification will be created with which the product will be developed further. The
gearbox design will be carried out after finding the gear ratio requirements.
The Schematic of drill drivetrain is given as:
The below image illustrates the various parts and the power transmission line of
the drill operation. The power flows from the hydraulic motor to the Gearbox then
the modified power flows to the drill rods and reaches the drill bit.
The drill string is the part which is used to increase the depth of the mining hole.
To drill deep hole very long drill string is required but practically carrying the long
string is difficult so that the drill strings are to be connected as a separate assembly