by Jeremy Lauzon, President at Hydracore Drills Ltd.
Typical exploration drill heads have not advanced in design over what Boyles, Longyear and others supplied in the 1970s. Why buy a new drill that has a drill head based on technology that is 50 years old? Drillers are used to the problems with these drill heads, and they try to work with what they have. Even if there was a drill with a better head the expense of replacing the entire drill might be a deterrent. This is why Hydracore came up with a cost-effective solution that allows you to upgrade your current drill. We call it the ‘Hydracore Drill Head Replacement Program’.
The Head Replacement Program all started with a call from a client that owned an EF-50. They liked the machine, but the drill head was a constant source of problems. One program alone cost over USD 28 000 in drill head parts for a single rig. Mark, the mechanic in charge of repairs, had previously worked on Hydracore HC2000 drills. It was his idea to convert the drill head to a Hydracore. The changeover went seamlessly and the increase in reliability was incredible. Word quickly spread through the industry and we have now made many successful conversions with most coming back for a second or third.
Mark knew that eliminating problems saves money. Using Hydracore’s 50 years of experience and long-term policy of simpler designs with less parts we have developed ‘H’ and ‘P’ drill heads that eliminate the common problems associated with other heads. These designs have been refined over a 15-year period; hundreds are currently in use. Make the move, I doubt you will miss broken gears, tearing apart your chuck and constantly fighting to chase down the next oil leak.
What is the impact of these problems on your bottom line? When your client sees your drill down for repairs on a regular basis will they call you back next year? Do your drillers want to miss out on their meterage bonus due to broken equipment? Maybe this causes your best employees to look for work elsewhere? A lot of the costs are impossible to quantify, but the direct costs and missed revenue associated with the downtime can be estimated.
We spoke with several clients running drills manufactured by other leading suppliers in Canada. In many cases it was found that the drill head was the ‘Achilles Heel’ of their drill. We discussed the repairs made, and the time and cost required to complete these. It was found in several cases that spare drill heads were supplied on every job due to the frequency of failure. This gave us the confidence that the market was ready for change.
Hydracore drill heads have less than half the parts of a conventional drill head.
The problems and the costs associated with them
Let us examine each problem individually, in terms of the costs associated and the solution achieved. For this comparison we will use the revenue per 10-hour shift at USD 3250 – 5000 and repair work as USD 120/hr. In cases where the repair can be completed by a driller during their shift no extra cost is added for repair labor.
The common gearbox found on most core drill heads is a Funk 23000 Series. These are rated by the manufacturer for a maximum input of 100 hp (75kW), 200 lb-ft (271Nm) and no-load speed of 3000 rpm. Drill manufacturers have been greatly exceeding these ratings which results in frequent gear failures. The broken gear teeth from this catastrophic failure often enter the drill head housing. The gearbox will need to be repaired or replaced and the drill head completely disassembled for inspection, repair and cleaning before drilling can re-commence.
Hydracore has solved this problem by using a large Bent Axis Variable Displacement hydraulic motor that has sufficient range of adjustment in speed and torque to eliminate the need for a gearbox. The Hydraulic motors last for five to ten years and are easily replaced in the field in one to two hours.
Oil leaks from the drill head housing
Gearboxes and head housings on common industry designs house a combination of gears, chains and bearings. All of these items require lubrication, and typically an oil filled head is used to satisfy this need. The oil filled head introduces unavoidable leaks that are unsightly and potentially damaging to the environment. If a client requires an inspection of your equipment, oil leaks from the head are generally on their checklist.
Hydracore Drill Heads are 100% leak proof! We have a bit of an unfair advantage here as our heads do not have any oil in them. Our design incorporates a carbon belt drive system, rated at 500 HP, the system gives us two benefits: one, it does not require any lubrication and second, with no metal-on-metal wear it is virtually maintenance free.
In a chuck type drill head, large diameter bearings are required to accommodate the drill rods to pass through the center of the main spindle. With large bearings comes a great deal of friction and therefore power you could use for drilling is wasted producing heat. The chains, gears and large bearings create a need for an oil lubrication and heat removal system. The lubrication system typically incorporates a lube pump, filter and in some cases a radiator. This type of system adds another unnecessary complexity that can and will eventually fail. Unless caught immediately, failure of the lubrication system requires a complete rebuild of the drill head which is a costly affair.
Through a careful design process, we have optimized our bearings to handle both the high speeds and high loads without creating excess heat, there are only two bearings in the entire head. The reduction in heat and lack of gears and chains means we have eliminated the need for oil, lubrication pumps, filters and radiators. A couple of shots of grease daily is all that is required to have a cool running head.
Chuck release bearing and release cylinder failure
The industry standard Drill Head Design uses a central release cylinder and typically two release bearings. Due to the diameter and speed of the main spindle, the designers were left with only brush seals to prevent the dirt and water from entering the release bearings and release cylinder. Brush seals are exactly as they sound and if you tried to use a brush to sweep up muddy water, you can imagine what passes through them. The bearings and piston seals fail in short order once the contamination passes the seals. If you are lucky, just the piston seals and bearings need to be replaced but often the piston and expensive main shaft become scored and need to be replaced as well. Access to these components is a large job and requires a complete disassembly of the chuck.
Hydracore’s unique drill head design does not require release bearings. The release cylinders used are externally mounted and designed to require a single piston seal. The design of these cylinders also allows for a standard wiper seal to protect the cylinder from contamination. If a leak does occur, the cylinders are mounted to the outside of the chuck and can be replaced in minutes.
Yearly expenses summarized
Industry standard drill head
Hydracore Drill Head
Massive benefits + no risk = easy decision
It is easy to lose sight of the total cost overruns when faced with these problems one at a time. Adding the costs to the lost revenue and organizing them into a logical manner displays how quickly these problems add up to a considerable sum.
Hydracore is confident in the reliability and cost savings of these heads. Three-month demonstration units are available to qualifying candidates for field testing. Adapting your drill to work well with another head is not an easy task. We have done the heavy lifting, so you don’t have to.
To date, all clients that have completed and tested the Hydracore head conversion have experienced immense success motivating them to convert more of their units:
‘The Hydracore head has been excellent for our drilling operations. It’s able to run HW casing through the head which is a big plus. The EF-50 drill has great features, except for the head. Running hydraulic oil through it has been a nightmare, we’ve had to rebuild it countless times. Now with the Hydracore head there’s no more worries. Two grease nipples are all there is for lubrication, the cylinder for the actuator is awesome, and easy to replace. Also, the support we’ve received from Hydracore has been amazing.’ Moe Debler – Drilling Manager
Have we opened your mind to the importance of the right drill head? I hope so, as the benefits for your business, your employees and the environment really make this an easy decision.
For more information visit: www.hydracore.com
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