Jumbo Drilling and Ground Support Operations

Summary

This comprehensive guide details the procedure for operating a jumbo drill and ground support in a mining environment. It outlines critical safety steps such as inspecting the work area, ensuring ventilation, and avoiding misfires before commencing drilling and scaling. The process covers equipment setup, including positioning the trailing cable, anchoring, and drilling for ground support. Key actions include scaling walls, installing split set steel bolts, and drilling lifters according to an approved plan. The script emphasizes safety, precision, and following drilling plans to ensure the integrity of the excavation and prevent accidents.

Takeaways

• 😀 Always park the jumbo at the sign, lower the jacks, and turn off the engine before proceeding with any inspection.
• 😀 Inspect the work area thoroughly, checking the ground conditions, walls, ventilation, and any misfires or explosives before entering.
• 😀 If misfires or uninitiated explosives are identified, immediately exit the area, re-hang the sign, and contact your supervisor.
• 😀 When setting up the jumbo, anchor the trailing cable to an approved anchor point and ensure it is kept off the ground and out of water.
• 😀 Only proceed with scaling operations after confirming the jumbo is correctly parked under supported ground and the jacks are lowered.
• 😀 During scaling, use 63-64mm drill bits to prevent accidental drilling into butts and misfires, and ensure the boom is positioned safely.
• 😀 Always do a final inspection of the ground conditions before commencing ground support operations.
• 😀 Use a 43.5-45mm bit when drilling holes for split sets and ensure the split sets are correctly installed without overdriving them.
• 😀 Make sure mesh sheets are correctly positioned and overlap as per the survey memo before securing them with split sets.
• 😀 Do not start charging the face until drilling operations are fully completed and the jumbo box isolator is turned off.

Q & A

What is the first step the operator must take upon arrival at the work area?

The operator must stop and park the jumbo at the sign and barricade. They should ensure the jumbo is parked with the jacks lowered to the ground and the engine turned off, and conduct an inspection of the work area.

What are the key items the operator needs to inspect when entering the work area?

The operator should inspect the ground condition, the walls and backs, the condition and location of mine air and water surfaces, ventilation within 20 meters of the face, and check for misfires or uninitiated explosives.

What should the operator do if misfires or uninitiated explosives are found?

If misfires or uninitiated explosives are identified, the operator must immediately exit the area, re-hang the sign and barricade, and contact their supervisor.

What steps should the operator take to set up the jumbo before beginning scaling operations?

The operator should tram the jumbo to the jumbo box, anchor the trailing cable to an approved point near the box, position the jumbo under supported ground, and connect the air and water hoses while ensuring the trailing cable is off the ground and kept dry.

Why is it important to start scaling operations on the backs?

Starting scaling operations on the backs allows all loose material to be removed from the walls and backs, which prevents any falling debris from causing harm during the scaling process.

What size drill bit should be used during scaling, and why?

The operator should use a 63mm to 64mm drill bit during scaling. These bits are stronger and larger, which helps prevent accidental drilling into butts and misfires.

What should the operator do to prevent damage when scaling large fragments?

The operator should position the boom to the side of any large fragments being scaled, ensuring that any falling debris does not damage the boom.

How should the operator ensure the split sets and mesh sheets are properly installed?

The operator should drill a hole 100mm deeper than the length of the split sets, partially install the split set into the hole, adjust the mesh sheet using the drill, and ensure the dome plates are firmly applied without over-driving the split sets.

What precautions should be taken during drilling operations in the face?

The operator should start by drilling lifters first, ensure all drilling and boom functions are disabled when inserting lifters, and always use caution, as drilling may loosen previously scaled ground.

What is the process for completing drilling operations on the face?

Drilling operations must be completed in accordance with the approved drilling plans. The operator should alternate between drilling on each side of the centerline, ensuring the angle and position follow the plan. Once drilling is complete, the jumbo box isolator should be turned off, and the trailing cable and water services safely stored.