Unconventional Hammers

There are drills not always used in the water well industry that are great tools with unique benefits.

By LaTisha Shipman

I know Water Well Journal is intended for groundwater professionals in the water well industry, and I normally address hammer issues within the spectrum of water well applications. I am also certain, though, that some groundwater professionals often drill wells unrelated to their normal range of drilling activities.

So, I would like to tackle some unconventional hammers and hammer oddities, at least for this industry. For those in the construction or mining industries, these hammers could be the tools used every day.

Water Hammers

First up, is a water hammer (Figure 1). Rather than using air to actuate the piston, this hammer uses water as its power source. The water hammer setup is significantly more expensive than running a DTH hammer, and the hammer itself is more expensive as it requires extremely precise machining techniques.

The water pumps and filtration system needed for operation are also more costly as compared to an air compressor. This is of course unless you are perhaps buying a new air compressor, and then things may be comparative in price!

This specialty hammer is used primarily in projects where environmental safety is of utmost importance such as dam or canal reconstructions. There is no oil used in the hammer, as the hammer parts are chrome plated and the tolerances are much tighter than conventional hammer parts.

Another benefit of using a water hammer is when drilling in congested areas or protected areas where the soil cannot be disturbed or disturbed the least amount possible, as drilling with water rather than air is less brutal to the surrounding geology and infrastructure. Areas like downtown in a congested city or places protected due to historical value are ideal spots for jobs using a water hammer.

The application for the water hammer is typically construction and in urban areas for foundational repair. The water used to power the hammer has to be finely filtered. This is done using a high-pressured water pump and filtration system.

As you probably can imagine or already know, air drilling in urban areas has its challenges. Among them are noise, the cost of noise barriers, and limited working hours to comply with noise regulations. The water hammer is the answer to these challenges as it is a quieter method of drilling.

Another argument for using water hammers is there is less fuel consumption associated with this method of drilling. The water pumps are more efficient than air compressors used for conventional DTH drilling.

While you would have to account for wastewater management, the water is normally refiltered and recycled, and there is little to no dust. The filtration must be less than 50 microns with max solids content 150 mg/l.

I know of at least one U.S. manufacturer for water hammers, Drill King International.

Cluster Drills

Next, I’d like to introduce cluster drills or canister-style hammers. Center Rock calls it the LP or XLP drills. These are somewhat like a conventional hammer on steroids.

This “canister” has several custom DTH hammers installed to drill a larger OD hole without investing in a larger hammer. Even with their smallest canister, which takes three 8-inch hammers, the OD of the tool is 24 inches—and they have the capability to make custom sizes up to 168 inches! How impressive is that?

You may recall the Chilean mine rescue that unfolded in 2010. I remember the day clearly. I was working for Drill King at the time and the day started with a flurry of phone calls that morning from our customers in Pennsylvania and West Virginia, experts in the oilfield and coal mines who were called upon for assistance.

Drill King was able to send bits to drill for the ventilation shaft, but Center Rock was one of the real heroes on the project. It was the company’s LP Drill that ultimately helped free the miners as it drilled the 26-inch shaft which the miners were lifted through. It was an incredible day!

I hope you’ve seen The 33, the movie that tells the story of the rescue. If you have not seen it, I highly recommend it to all drilling enthusiasts.

So back to the cluster drill. This method of drilling is used in construction, piling, and even HDD and utility pole driving. It is impressive in its flexibility in the market as well and used for many different applications where a larger diameter hammer is needed.

A Hammer Prototype

Lastly, I would like to mention the hammer that intrigues me the most. I have seen a prototype mud hammer that utilizes PDCs and tricones for the mining and blasting industry. The concept truly amazes me, and like other drilling tools that are generally designed with other industries in mind like oil and gas or mining, I believe this concept will eventually trickle to the water well industry.

Research and development is always time-consuming and expensive, and the water well industry isn’t always able to absorb the costs associated with it. However, the mining and oil and gas industries are often able to finance such R&D, and the water well industry can then eventually benefit from these inventions after they are tested and proven to work in the field.

We already have a fluid hammer, as was mentioned at the beginning, but the WAI Water Hammer cannot run drill mud through it—at least not without a significant redesign of the internal hammer parts and then we lose the functionality of the hammer.

I feel like this type of mud hammer would be beneficial in the water well industry. It has the potential to increase the rate of penetration while mud rotary drilling, thus effectively reducing the cost per foot.

If you’re up for reading a 35-page test result from a collaboration between Novatek and the U.S. government, visit www.netl.doe.gov/sites/default/files/2018-05/final_34365.pdf. It’s an interesting and detailed account of the manufacturing process and field testing of one of these hammers.

The report is dated “9/30/1997 – 9/1/2005,” so this is not new technology. However, I don’t believe this hammer is being mass produced anywhere right now. I think there was a manufacturer producing them for a time, but it’s no longer in their product offerings. I’m not privy as to why it’s no longer being offered. Perhaps it only works in theory or is too expensive to manufacture.

Maybe one day we can get a mud hammer! I think for that to happen, we would need to see meaningful collaboration between hammer manufacturing experts and PDC and tricone manufacturing experts. They are not always the same.

LaTisha Shipman is in sales for Petra Drilling Supply in Texas. She has more than 20 years of experience in the drilling industry with most of that time spent working in manufacturing with DTH hammers and bits. She can be reached at (817) 517-1308 or tisha@petradrillingsupply.com.