At Stratum Drilling Solutions we all too often get asked: "Why should we spend money on tooling services?" With costs being at the foremost of companies thinking the servicing of consumable often has to take a back seat. However, what we often put across is the costs against the life of the equipment can be extreme if servicing is not undertaken.

If we look at DTH equipment which consists of around 70 per cent of our workload for servicing, having worn or poorly functioning hammers can cause a huge decrease in productivity on site. This is even more apparent when looking at the cost of a drill rig/crew/auxiliary equipment/air etc. Due to the very precise tolerances, once a hammer over wears and this goes unchecked, production will dramatically decrease.

Here at Stratum Drilling Solutions, we have a large rental fleet consisting of hammers ranging from 2 - 24in, each time one is returned it is stripped, cleaned and serviced, and the wear limits are documented. This methodical approach allows us to monitor the effective cost per metre and to plan when a replacement is required. Turning up to the site and a hammer not firing is far more costly than a simple repair.

Further adding to DTH productivity is something that frequently gets overlooked - the carbide on bits. Rotating the tools too fast or too slow wears down the carbide, a 25 per cent reduction can cause up to 50 per cent of penetration loss.

Simple grinding can eliminate this and can be easily carried out on site or in a workshop. Grinding also helps to eliminate vibration travelling back up into the shank, too much vibration can cause a catastrophic failure. Once the shank has broken or worn then the bit will be scrap.

However, a common misconception is when there is a loss or break of carbide then the bit is finished. This is not the case; we have a machine called a Spark Eroder than allows us to replace the carbide. This process effectively gives the bit a second use, generally, the shanks will be fine and will have considerable life left in them.

The above also applies to our auxiliary equipment like oilers and mist/foam pumps. Making sure these are functioning properly each time they hit site is important. If, for example, an oiler is not injecting the required volume then the hammer will simply wear quicker. An older hammer will undoubtedly have wear on the piston and its housing and oil helps to seal this and allows the hammer to function more efficiently. The more efficient the hammer, the better the penetration. Remember oil is far cheaper than pistons.

Grout plant we find to be one of the products that need the most daily maintenance, due to the fact that grout solidifies and wears all parts of the plant need to be cleaned at the end of each shift. Again, this is to minimize daily downtime. We have found that grout plant that does not get regularly cleaned will often need to have up to 50 per cent more part replaced during a service and some of those parts can be expensive and integral to the plant's operation.

Part of our tooling service and repair operation is full identification, strip, clean and rebuild. For equipment that will not be used immediately, we will oil and seal DTH hammers for storage. Cataloguing is also an option that we offer and one that is becoming more popular.

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Andrew Robertson is a director of Stratum Drilling Solutions, a UK-based a full-service drill rig sales, service and repair business and supplier of complete solutions of drilling consumables