Horizontal directional drilling (HDD) was a lot of trial and error back in the 1970s. It was a new territory, and the only reason it succeeded was due to the perseverance and tenacity of its early pioneers. This practice has now been perfected for more than 40 years in the trenchless construction industry.
Technological advancements have also enhanced horizontal directional drilling fluid’s performance, while decades of expertise have resulted in best drilling and trenchless construction practices that are now universally recognized by professionals.
So, why is it that drilling fluid is still undervalued?
Drilling fluid, sometimes known as “slurry,” or “mud” is a liquid made up of water and additives that aids in the horizontal directional drilling process. Removing cuttings from the bore, controlling formation pressures, cooling and lubricating the bit, sealing permeable formations encountered while drilling, transmitting hydraulic energy to downhole tools and the bit, and, most importantly, maintaining borehole stability and control are all functions of drilling fluids.
Bentonite and polymer are the most commonly used additives in drilling fluids, accounting for around 3% of the whole mixture — sometimes a combination of the two, depending on the conditions of the ground. A bentonite is a form of clay that may be refined, powdered, and mixed with water to create a mud-like fluid that is used in the drilling process, thus the word “mud.”
A drilling fluid works far better than water alone in stabilizing the borehole, suspending cuttings, and carrying them out. Without it, drilling efficiency can be harmed, the equipment can be damaged, and the likelihood of frac-outs and other site damage may be higher.
Unfortunately, some HDD operators are put off by the cost and apparent difficulty of “doing it right.” As a result, they break the crucial drilling fluid guidelines on a regular basis, unaware of the dangers they’re putting themselves in.
Many underground professionals emphasized the importance of having a well-performing drilling fluid for every trenchless project, and this can be attained by following some important practices.
A Skilled Mud Man Must Be Designated.
One common blunder made by many HDD operators is failing to have a trained crew member in charge of the drilling fluid. Sending a laborer to “top it off” when the mud runs low may appear harmless, but it might actually impede your drilling efforts.
At any given point in a typical hole, fluid returns contain roughly 20% solids. Incorrectly mixed mud—that is, mud that has been “topped off” by someone who doesn’t know what they’re doing—has a significant danger of bringing back solids into the hole again and putting whatever progress you’ve made in jeopardy.
These extra particles can clog the annulus, wear down pump parts, create torque loss, and raise torque and pullback pressures. This causes the drill pipe to become jammed down the hole, possibly resulting in inadvertent returns. Thus, designating a qualified mud man in every horizontal directional drilling project is crucial.
A Mud Engineer Must Be Available On-Site.
A mud engineer collaborates with a qualified mud man. This professional, who is usually recruited from a drilling fluid company, checks the fluid every hour or so to make sure the recycler is working well and the mud mix is still optimized for current conditions.
A mud engineer is someone familiar with the fluid and analyzes its efficiency while on-site to get the most out of the drill. A mud engineer, for example, will know the correct polymer to add to the mix to remedy the problem and keep the operation operating smoothly if an operator is experiencing a high level of fluid loss.
Don’t Cut Corners When It Comes To The Mix.
Some operators will try to “save money” by not using the right fluid mix. For instance, they skimp on sodium carbonate or “soda ash” in their make-up water. Soda ash reduces the hardness of water and raises its pH to the levels required for effective drilling fluid performance. Unfortunately, if you don’t add soda ash to your water, you may need to use up to 50% more bentonite in your mixture.
When you “save money” by excluding additives, the costs can quickly mount up. Drilling fluid mix should always be dictated by geotechnical conditions, not budgetary constraints. The equipment will work harder than it needs to if the right mix isn’t used. It not only delays drilling, but it also puts more strain on your tools and equipment, reducing their service life and increasing the likelihood of malfunctions.
The expenses of maintenance, replacement, and job shut-down should be enough to persuade operators to utilize the right mix. Using the appropriate fluid mix will improve drilling performance and save you money and headache in the long run.
Don’t Use Your Mud Too Much.
Some operators use mud to the point where it is no longer effective. The inconvenience of mixing new mud, the cost of disposal, and, to be honest, laziness are all common reasons.
The issue is that mud loses flow properties when it becomes too heavy. It means you’re not getting cuttings back out of the hole as quickly as you should be, which can cause several issues and delays, including inadvertent returns.
Cutting corners does not pay off in the long run. With everything that can go wrong on construction, from hole collapses to equipment failure and more, trying to “save” on mud can wind up costing you more in the long run.
Final Thoughts
While the technology and chemistry of drilling fluids have advanced significantly, the basic notion has remained the same. Drilling fluids are critical to drilling success. Thus, keeping its efficiency at a maximum should be one of the top priorities.
