Training

People are our most valuable resource and yet we still don’t provide adequate operational training to longwall personnel. You can’t expect a $60 million longwall complex to reach maximum efficiency unless the people driving it have been thoroughly trained in all aspects of longwall operations.

Longwall mining is not rocket science. It is actually quite simple. Give the crews the right equipment and the right training, and the results will follow.

1. How do you rate your longwall training?

***** Absolutely brilliant! I know everything about longwalls

**** Very good. I received thorough training from an experienced longwall trainer (eg Joe Foy, Andy Rutherford, Steve Holmes …

Nick Wills*)

*** Average. I had some training from OEMs on the equipment

** I learnt by getting stuck in with the other crews

* What training*

Support automation

Powered support automation works. The sophisticated technology on a modern longwall is now very reliable and, given the correct training and the dedication of management and crews, it will work very effectively.

2. How would you rate your longwall automation?

***** Outstanding. Three or more shears without needing to press any buttons

**** Very good. We can do a complete shear with all the supports on auto

*** Average. We run shearer initiation but not at the gate ends

** We only use batch control of a few supports at a time

* We don’t use automation

High-pressure set system

The most effective means of ensuring adequate roof support on a longwall is to put the correct pressure into the leg cylinders. The minimum should be around 340 bar on a modern longwall. This will prevent “weak roof” and minimise downtime with costly roof falls.

3. How do you know your supports are set correctly?

***** We have a high-pressure guaranteed set system. The longwall does not run without it

**** We have a positive set system and it is monitored at all times

*** We regularly check the system pressure and the set pressure in the support legs

** Someone looks at it on the surface … I think

* I don’t know

Web depth

It is a common misconception that having a wider shearer drum produces more tonnes of coal. In fact the opposite is true. Every longwall operation I know of that has adopted a narrower web depth produces more coal, more safely!

4. What is your web depth?

***** 700mm

**** 800mm

*** 1000mm

** 1200mm

* Haven’t seen the drums for a while, we have a roof fall

Maintenance

As with any heavy-duty industrial equipment, maintenance is essential. You wouldn’t run your 4-wheel drive until it blows a gasket and breaks down, would you*

5. How would you rate your longwall maintenance?

***** Excellent. There are no leaks or bypasses

**** Good. We have regular planned maintenance and any leaks and bypasses are dealt with promptly

*** Average. We have probably 10+ bypassing legs and quite a lot of leaks

** Poor. We don’t have the budget to keep up with the hydraulic failures so we just don’t worry too much. The roof is always bad anyway

* We have two fitters and they are always busy

How did you do?

22 stars or more: Congratulations, your longwall is well managed and is probably producing vast amounts of coal. Or you might just be dreaming!

14-21 stars: The longwall goes quite well but it is obvious you could be doing much better. If you recognise this, there is hope that you can do something to improve the situation.

5-13 stars: Things really need urgent attention. If you are a manager, take action! If you are on the longwall crew, maybe you are working at the wrong coal mine?

Published in June 2009 Australian Longwall Magazine