Bottom Hole Assembly is a drilling equipment which includes special equipment, drilling yangdipakaipada certain operating conditions
– Bit Subs is a device connecting between the chisel drill with a tool thereon, dapatlangsungdenganDrill Collar, Near Bit Stabilizer, Down Hole Motor, orienting Sub and others. The size and type of thread adapted to a chisel in one hand and adjusted the equipment on top of the other side. Bit Subs always used in vertical and directional drilling operations.
– Pup joints are short pipe, used in the arrangement of vertical and directional drilling. Pointless to allow the placement of stabilizers and other equipment at the time will increase / decrease the angle of the drill holes.
– Stabilizer meupakan device connecting between Drill Collar but its main task is: Make a series of drill more rigid, so the pit straight; Differential Pressure Sticking reduce harm; By setting the distance placement around chisel drill and Drill Collar then the angle of the drill holes can be raised or lowered to achieve the goal of drilling; Avoid keyseat and dogleg holes.
– Down Hole Motor is a drill chisel players who are as close as possible to the drill chisel, so that the circuit does not need a rotating drilling during drill except chisel drill. Operation of this tool, a constant flow of drilling fluid; the stronger the flow of drilling fluid will increase the speed of rotation of the drill chisel.
– Drilling jar is a tool that can be installed on the drilling sequence, serves to provide punch upward during a clothespin on a series of drilling, in an attempt to release the clothespin. In general, the drilling jar mounted between drill pipe Drill Collar and since most parts are squeezed in a series of existing drilling and Drill Collar Drill pipe, so Jar did not participate pinched and can work with the pull Drill pipe. There are two kinds of drilling jar, namely mechanical and hydraulic drilling jar.
– Hole Opener is a tool to enlarge the diameter of the drill hole. The construction is like three cone rock bit, but at the bottom center there is a tail with a diameter smaller than the diameter of the hole long and become so enlarged holes guidance does not deviate from the old hole.
– Under reamer is a tool to enlarge the hole bottom bordibagian, for example below the casing shoe or in a certain formation that needs to be enlarged beyond the diameter of the drill hole on top.
– Shock absorber mounted on the bit for bit has a tendency to vibrate up or down the bottom of the hole when the hole formation tends to form zigzagged during drilling or while mengembor in. Vibration will damage the surface equipment and will meurunkan optimization WOB and rotary speed, bending, drill stem, damaging the bit.
Graph 4.29. Bottom Hole Assembly: (a) Bit Sub; (B) Joint Pup; (C) Stabilizer; (D) Down Hole Motor; (E) Under reamer; (F) Hole Opener; (G) Drilling Jar; (H) Shock Absorber