There are many types of drilling fluids. The various types of fluid generally fall into a few broad categories:
- Air: Compressed air is pumped either down the bore hole’s annular space or down the drill string itself.
- Air/water: The same as above, with water added to increase viscosity, flush the hole, provide more cooling, and/or to control dust.
- Air/polymer: A specially formulated chemical, most often referred to as a type of polymer, is added to the water & air mixture to create specific conditions.
- Water: Water by itself is sometimes used.
- Water-based mud (WBM): A most basic water-based mud system begins with water, then clays and other chemicals are incorporated into the water to create a homogenous blend.
- Oil-based mud (OBM): Oil-based mud can be a mud where the base fluid is a petroleum product such as diesel fuel.
- Synthetic-based fluid (SBM): Synthetic-based fluid is a mud where the base fluid is a synthetic oil. This is most often used on offshore rigs because it has the properties of an oil-based mud, but the toxicity of the fluid fumes are much less than an oil-based fluid.
A fluid tank is an open-top container, typically made of steel, to store drilling fluid on a drilling rig. They are also called mud pits or mud tanks. The tanks are usually open-top and have walkways on top to allow workers to inspect the fluid levels in the tanks. Other equipment is often mounted on top and the walkways allow access to that equipment. Recently, offshore drilling rigs have closed-in tanks for safety.
A drilling rig normally has two tanks. One tank is sectioned off into compartments that may include a settling tank, or sand trap, to allow sand and other solids in the drilling fluid to precipitate before flowing into the next compartment. Other compartments sometimes have agitators used to stir the fluid.
Mud tanks for solids control systems are divided into Square tanks and Cone-shaped tanks according to the shape of the tank bottom. The body of the tank is made by welding the steel plate and section, using the smooth cone-shape structure or the corrugated structure.
USA Tank’s factory-baked epoxy coatings provide the best oil field corrosion protection in the storage industry. Able to withstand saltwater and most acids, our liquid immersion coatings are suitable for most drilling fluids. USA Tank designs and engineers bolted tanks for higher specific gravity drilling fluids. USA Tank bolted tanks are low maintenance and durable to incorporate for a wide range of oil field applications.