The distinguishing feature of the dual-rotary (DR) drill rig is a lower rotary drive, which is used to independently advance casing up to 40 inches, depending on the drill model.

This month’s article focuses on the portion of submersible water system between the wellhead and the house.

Submersible pump accessories are the plumbing and electrical components of a pumped water system that are particular to a submersible pump system vs. a jet pump system. For simplicity’s sake, we will divide them into two categories – down-hole accessories, and aboveground accessories.

Check valves permit water flow in one direction only, and are required on all submersible pump installations.

To keep loose sand and gravel from collapsing into the borehole, it is necessary to use well casing and screen. The screen supports the borehole walls while allowing water to enter the well; unslotted casing is placed above the screen to keep the rest of the borehole open and serve as a housing for pumping equipment.

Reverse circulation drilling was developed to allow for larger borehole drilling without limiting the factors of drilling fluid pump capacities.

Drilling muds have four basic properties that determine the behavior of the mud as a drilling fluid – viscosity, density, gel strength and filtration. Several other properties, although of lesser importance, need to be checked, especially if problems are anticipated or encountered.