Water Well Drilling: What Bit Type Do I Need?

/in /by

If you’re familiar with drilling at all, you know it’s all about the geology. It’s no different when drilling for water wells. Rock formation type, depth of the overburden, bedrock and the aquifer all play a role in how you determine the method of drilling and which equipment and drill bits you need. You might need roller cone bits, step drag bits, claw bits, chevron bits or PDC bits for water well drilling, but it’s dependent on the application. 

 

If you already know what type of bit you need, contact our team to make an order. O-K Bit is the world’s largest supplier of rerun bits, and we’re happy to provide you with whichever bits you’re looking for. 

 

Types of Water Wells

While you are probably interested in information about how water wells are drilled and what bits you may need, it’s important to note that drilled wells are not the only type of water wells. 

 

There are three primary types of water wells: drilled wells, dug wells and driven wells. Each has its own unique characteristics. 

 

  • Drilled Wells – Drilled water wells utilize a drilling rig and drill bits to bore into the earth. The bit rotates clockwise to create the borehole. As the bit breaks up the soil and rock beneath, the wells are drilled deep into the ground (often between 100 and 500 feet). 
  • Dug Wells – Dug wells are water wells that are created by digging a hole in the ground and lining the walls of the hole with brick, tile or stone. The hole is drilled to a level below the water table so that the water comes into the hole and can be bailed out. 
  • Driven Wells – These wells are made by driving pipe into the ground. Driven wells are relatively shallow (30 to 50 feet deep) and, therefore, they draw in water that is in aquifers close to the surface.  

 

All three types of wells penetrate below the water table into the aquifer below (although to different depths). The water from the aquifer is then pumped or bailed out through the well. However, driven wells and dug wells are more likely to be contaminated because they draw water from shallower depths which are more likely to have bacteria or contamination.  

 

How are water wells drilled?

Drilling water wells is a process that involves many steps. The lengthy process is valuable though because, if done correctly, a water well can provide water for a hundred years or longer. The process also helps drillers ensure they are equipped with the right tools and drill bits for successfully drilling the well. 

Steps for drilling a water well: 

  • Identify the desired location – Before beginning the process, it’s important to identify the well’s location and ensure an adequate supply of groundwater. If there is not an adequate water supply or the correct directional flow of water, you may need to select a different site. 
  • Evaluate the site of the well – evaluating the site is an important step for determining the desired depth of the well, understanding the rock formations present and selecting the equipment needed for the well. This includes choosing the correct drill bits for your water well drilling site. 
  • Drilling the well – drilling the well will involve setting up the drilling rig, drilling the borehole and installing the casing and screen. 
  • Pumping and evaluating – after the drilling, the pumped yield of the well will be evaluated and then developed. For most wells, there will be fine materials (minerals and sediment) that need to be removed so the water more effectively moves into the well.
  • Testing and disinfecting – The water will then be tested for quantity and quality. The well will be disinfected. After the water well is successfully drilled, it will be capped (for sanitary protection) until it can be connected to the customer’s system. 

 

Bits Used for Water Well Drilling 

A wide variety of drill bits are used for water well drilling. The rock formations of the drilling site will determine which bits are needed, but the O-K Bit team is equipped with whichever water well drill bits you need. 

 

The following bits are commonly used for water well drilling: 

  • Step Drag Bits 
  • Roller Cone Bits 
  • PDC Bits 
  • Claw Bits 
  • Reamer Bits 

Step Drag Bits 

Step drag bits are commonly used for drilling pilot holes. They are useful in this application because their cuttings are easiest to log and they are able to drill quickly. They are durable and hard, which means they have the longevity that many other bit types lack. Step bits are also used in sand, clay and other medium-hard rock formations throughout the drilling process. You should avoid using step bits in hard or coarse gravel rock formations because they will not be able to shear effectively. 

Roller Cone Bits 

Roller cone bits are identifiable by their rolling cone inserts. These cutting structures are useful for drilling through tough soil and rock. The tungsten carbide inserts are durable and self-cleaning, so as they crush and chip hard rock formations they remain productive. These bits are used at lower penetration rates, but they are especially effective at breaking up hard rock. 

PDC Bits (Polycrystalline Diamond Compact Bits) 

You may use a PDC bit for a water well drilling application if you hope to drill very precisely in soft to medium rock formations. These bits utilize a synthetic diamond compound on the cutters to create a highly durable and productive cutting structure on the bit. PDC bits are able to achieve high penetration rates while in use. 

Claw Bits

If your water well drilling site has a high volume of clay, a claw bit may be useful as you drill your water well. A claw bit is designed to use its uniquely shaped fingers to dig into and loosen hard clay that otherwise would be difficult to bore through. These bits are highly durable and the cutting structures (the fingers) can be replaced when worn. 

Reamer Bits 

Finally, reamer bits are often used in water well drilling to widen the borehole and keep the hole straight. The cutting surfaces of these bits are attached below drill pipe which then aids in keeping the hole straight and prevents bits from becoming gummed up with clay. Most commonly, reamer bits are used in sandy soils or clay formations. 

Well Drilling Methods

There are a wide variety of well drilling methods and techniques. The best approach will likely depend on the unique conditions of your drilling site. A few of these methods are: 

  • Down the Hole Drilling 
  • Air Rotary Drilling 
  • Bucket Auger Drilling 
  • Cable Tool Drilling 
  • Reverse Circulation Drilling 
  • Mud Rotary Drilling 

Regardless of the method or location of your water well drilling, O-K Bit is here to help you select the best new and rerun bits for the job. Contact our team today to order the supplies you need for water well drilling.

What Drag Bit Do I Need? Chevron Vs. Step

/in /by

Drag bits are used for drilling across a wide variety of industries – from mining, water well, and geothermal drilling to natural gas and oilfield drilling. Because they are used in various environments and applications, drag bits are some of the most popular bits used worldwide. 

There are different varieties of drag bits, but the most common are chevron drag bits and step drag bits. Depending on your formation type and density, the ideal size of the bit and style may vary.  If you’re questioning, “What type of drag bit do I need?” you are in the right place. We’ve outlined chevron bits vs. step bits here, but you can always ask the experts at O-K Bit, too! 

O-K Bit is a leader in providing new and refurbished bits for any type of drilling in nearly any formation. Contact O-K Bit today, and our team of knowledgeable experts can supply the products and information you need. We’re always happy to guide customers to the best bit for their specific drilling project. 

When should I use a drag bit? 

A drag bit is probably your best bet if you are attempting to drill through soft formations like clay, sand, and some very soft rocks. They are designed to work well in soft formations, but if you are drilling in harder or more rocky formations, you might need to explore tricone, PDC, or another bit type. 

Drag bits are often used to drill pilot holes. If you are looking to sample and log a series of cuttings, a drag bit would be helpful to complete this work. Because of the design and cost of drag bits, they can also be more economical for drilling. 

How does a drag bit work? 

Drag bits, including chevron bits and step bits, are most often made of alloy steel, but they can be manufactured using tungsten carbide. Some are solid cast, and others are welded. The construction of tungsten carbide bits makes them more durable. Tungsten carbide bits may serve you better if drilling in a rocky formation or for other specialty purposes. If you’re drilling in sand or clay, an alloy steel bit will probably suffice. The cutting structures vary on chevron drag bits and step drag bits. Still, both designs feature a central opening with radial cutting structures or wings. 

To understand how drag bits work, imagine you’re drilling a small pilot hole in a wall with a tiny household drill bit. After it’s drilled, that pilot hole can then be used as a guide for a larger bit to bore through. Drag bits work in the same way; the tip of the bit essentially creates a pilot hole for the rest of the cutting structure to shear and expand the hole. Drag bits do not have the fastest rotation or rate of penetration (ROP), but they are effective and can be very precise. 

Another benefit of drag bits is the simplicity of design and lack of rotating parts. While roller bits or others may become stuck in soft formations, drag bits often drill more efficiently and require less maintenance. 

Step Drag Bits 

Step drag bits are one common type of drag bit and one of the most common bit types used worldwide. As the name indicates, the cutting structures of these bits feature a stair-stepped design. They are pointed at the top, stairstep down, and become wider at the base of the bit. Step-type drag bits can have three or four wings. Four-wing bits are typically more durable and longer lasting. You’ll also find them more precise and able to drill a straighter hole. Three-wing step drag bits tend to drill faster but with less precision.  The number of steps usually depends on the size of the bit. 

Uses for Step Drag Bits 

  • Drilling in sand, clay, shale, limestone, and some gravel 
  • Sampling and logging cuttings – because the design provides larger cuttings 
  • Drilling efficiently – step drag bits can maintain rotary table speeds of 60 to 80 rpm 
  • Drilling for water wells, mining, geothermal, environmental, and exploration drilling

Chevron Drag Bits

Chevron drag bits are the other typical style of drag bits. Three or four wings create the cutting structure of chevron bits in a radial formation. Each wing is pointed at the tip and widens towards the base. Each wing forms its own chevron shape, as the name indicates. Like step drag bits, chevron bits can have three or four wings. The tips of the wings are often made of tungsten carbide or another highly-durable material to strengthen the bit and attack difficult rock formations. 

Generally, chevron bits are more durable than step drag bits and can successfully drill in more rocky and abrasive formations. Another feature of the chevron bit is its ability to drill through plugs and concrete casings. If you get stuck in a jam, the chevron bit can probably bail you out – it really is a robust and vigorous bit that can be used almost anywhere. You’ll find using a chevron bit requires more pressure on the bit, and the drilling process may be a little slower than a step bit. 

Uses of Chevron Drag Bits 

  • Drilling in both soft and medium formations, including shale, sandstone, limestone, other rock formations, casings, and concrete 
  • Drilling slowly in harder formations and maintaining a consistent borehole – 50 to 60 rpm is typical 
  • Drilling for water wells, mining, geothermal, environmental, and exploration drilling

So, What Kind of Drag Bit Do I Need?

Without understanding the geology and environment in which you are drilling, it’s hard to say exactly which type of drag bit you need. There are a few things you can consider to help determine which drag bit is best, though. Is your rock formation soft and porous (step bits), or is it a medium to hard formation (chevron bits)? Do you prefer to cut through the rock very quickly (step bits), or slowly and steadily (chevron bits)? Do you need to collect cutting samples to log (step bits)? 

After learning more about step drag bits and chevron drag bits, the answer may be pretty clear-cut. If it’s not, that’s okay. Choosing the right bit can make all the difference to the cost, efficiency, and success of your drilling project. We understand you want to make the right decision. O-K Bit is ready to help. Our team is the world’s largest retailer of refurbished bits in the world, and we really do know our stuff.  Contact us today to get started.

Your Guide to DTH Drilling

/in /by

Pneumatic tools have been used to drill through rock since the 19th century. Back then, drillers would suspend themselves from a rope over a quarry face to put a drill from the right position and use small diameter holes. The process was inefficient and dangerous. It could send rocks flying and the accuracy was subject as much to luck as it was skill. After a while, drilling crews started carrying jackhammers on masts, beautiful boreholes were misaligned, the explosives that followed could be even more dangerous.

Thankfully, we live in the modern era, where down the hole (DTH) drilling has become one of the most efficient and safest methods since its invention in the mid 1950s. Let’s explore what DTH drilling is, why it’s such a successful technique, and how it might be the perfect process for your drilling operation.

What is DTH Drilling and how does it work?

DTH drilling is a drilling method that’s used to crush rock by using a drilling hammer to hit hard rock repeatedly. DTH drills are pneumatic tools that provide power by driving compressed air into a piston inside the hammer. This type of drilling has made it much easier to drill wells quickly and efficiently by allowing contractors to switch from dirt boring to rock boring simply by adding a compressor and hammer to a drill bit.

Before DTH became a widespread drilling technique, contractors would desert a dirt bore project after encountering hard rock, leaving it to a different set of drillers to continue. With DTH drilling, the same drilling team can work through multiple materials.

At its most basic level, DTH drilling involves attaching a drilling hammer to the bottom of a drill string. Small, percussive hammers are placed above the drill bit, allowing drill pipes to exert a feed force necessary to rotate the hammer and bit together with fluid (usually air, water, or mud). This actuates the hammer and flushes the cutting. Drill pipes are then added to the drill string as the hole gets deeper.

Because the air-powered piston strikes the bit directly, energy is transferred down the hole, minimizing any lost energy. This allows drilling to greater depths.

DTH Drilling is most often used in the mining industry, where blast hole drilling is necessary for projects like water well drilling, building construction, and oil and gas processes.

Types of DTH Drilling Hammers

DTH hammers are fully fluid actuated. There are two primary parts: a valve which controls the flow and a piston that strikes the impact surface. The hammer body allows for stable, straight guidance of the bit. There are three types of hammers that depend on the actuation fluid:

  • Air hammers – These are typically limited to shallow holes of less than 200 meters.
  • Water hammers – These require a lost water flow of between 55 and 744 L/min depending on hammer size to actuate the hammer. These allow for better borehole control and greater depth than air hammers.
  • Drilling mud hammers –  These are the newest types of drilling hammers, but they’ve shown a lot of promise so far. They’re able to drill on every existing drilling rig by using classical mud composition. They are fantastic choices for drilling into hard rock in geothermal projects due to their ability to drill extremely deep.

What are the benefits of DTH drilling?

DTH drilling is extremely effective, which is why we’ve been using it for the past seven decades. Some of the major benefits include:

  • The use of air is extremely efficient. You don’t have to buy, source, treat, or transport it for use.
  • DTH systems are simple to adapt to most directional drills, and it doesn’t take long.
  • Very little rotational torque is required to cut rock that will allow the hammer to drill straight.
  • The same drill can be used to drill through both dirt and rock.
  • There isn’t as much wear and tear on a drill bit since the hammer is doing most of the work.
  • There is a smaller carbon footprint than other techniques due to the use of less drilling mud and additives that need to be disposed of.
  • It can be used more often in cities because it produces less noise and vibrations than alternatives. 
  • Fewer amounts of additives and drilling fluids are required than for alternatives.
  • The rate of penetrations is up to five times greater than rotary drilling techniques.

OK Bit has the DTH Drill Bits you need

If you’ve decided DTH is the right drilling method for your project, OK Bit can supply you with whatever bits you need to get the job done. If you aren’t sure if DTH drilling is the best choice or if you need help choosing a specific hammer or bit, our expert staff will be happy to help. Contact us today.

a geothermal energy site

Geothermal Drilling and Energy: A Simple Guide

/in /by

When it comes to drilling for energy sources, efficiency is the name of the game. The less energy you use to access more energy sources, the more efficient the system. This is beneficial for both financial and ecological reasons. It costs money to use energy, and wasted energy releases greenhouse gasses that pollute the planet. But what if you could harness energy that already exists beneath the surface of the planet? Geothermal energy aims to do just that. Let’s discuss the geothermal drilling process as well as its benefits.

What is Geothermal Drilling?

Geothermal energy is the heat produced deep beneath Earth’s surface in the core. It’s created naturally through geological processes. This energy exists whether we use it or not, and even if we do, it renews as geological processes continue. The only challenge is accessing it. The most useful stash of energy exists between two and twelve miles under the surface, so special drilling technology is required to reach it.

 

Geothermal energy isn’t new, but it’s been increasing in popularity in recent years. This is especially true in Iceland, which transformed itself over the 20th century in large part by pioneering geothermal drilling. Now, 66% of the country’s primary energy use is derived from geothermal sources. Other countries are quickly catching up. As of 2021, it accounted for only .4% of energy in the USA, but that number is increasing quickly. Many see it as a method of the future.

How Does Geothermal Energy Work?

Geothermal well drilling varies in its methods. While some wells only need to be a few hundred feet deep, some reach depths spanning several miles. The most common method for extraction, often called conventional geothermal drilling, uses hot pressurized water near the surface to produce energy. Drillers pump the water up, extract its heat, then reinject the cooled water. Unfortunately, this method only works in areas with underground pools of hot, pressurized water, and these can be hard to find. Iceland’s success is largely due to an abundance of these pools

 

However, there is a newer, more practical extraction method called enhanced geothermal drilling. In this process, wells extract energy from non-porous rocks. Drillers inject water into a well, force it through fractures in hot rock, and pump it out of another well to extract the heat. There are still some engineering-related problems to overcome, but it’s widely considered to be the future of geothermal drilling.

 

What are the Benefits of Geothermal Energy?

 

  • Environmentally sustainable – Unlike traditional fuel sources like fossil fuels, geothermal energy produces essentially no emissions. Nothing is burned, and there isn’t a finite amount of its source. Sure, there’s still a small amount of greenhouse gas production, but it pales in comparison to burning fossil fuels.

  • Highly efficient – Geothermal pump systems use 25-50% less electricity than conventional HVAC systems when heating and cooling.

  • Fully renewable and reliable – Geothermal energy is fully renewable thanks to naturally occurring geological processes, but it’s also exceptionally reliable. Unlike other renewable energy sources like biomass, solar, or wind, geothermal energy isn’t dependent on any external circumstances. It’s available at all times, during any sort of weather or any time of year.
  • Maintenance-free (mostly) – Because there are so few movable parts in a geothermal system, they rarely malfunction or break. Pumps usually last for more than twenty years, and the pipes can last for more than fifty years.

 

The Future of Geothermal Drilling

Geothermal technology is getting cheaper as technology advances. In the last forty years, the cost of running a geothermal power plant has declined by nearly 50%.  As of right now, only about 10% of the Earth’s surface is fit for power production, but as enhanced geothermal drilling becomes more widely available, this will continue to make geothermal energy more accessible and affordable. 

 

The potential is incredible. The amount of heat that exists within 10,000 meters of Earth’s surface contains a mind-boggling 50,000 times more energy than all oil and natural gas resources in the world, combined. It’s waiting to be used. By investing in geothermal energy now, you can be a part of a cleaner, more affordable, more renewable, and more reliable energy source than traditional fossil fuels.

Is Geothermal Energy Right for Your Project?

Whether you’re an industrial driller looking to improve or replace your bits or a DIY enthusiast looking to create a geothermal well for your home, OK Bit has the drill bits you need. If you have questions about your specific project or about geothermal drilling as a whole, our experts will be happy to answer any questions you may have.  Contact us today to get started.

OK Bits Services

Welcome To Our New Site

/in /by

 

We are very excited to announce the launch of our new website.