The circulatory system is one system that memegangperanan important in the operation of rotary drilling (rotary drilling) is the main .Tugas help system players inside the “drill” by providing the tools appropriate to regulate the materials mud and workplaces to prepare , maintain and replace the drilling fluid. The circulatory system is composed by four major sub-components, namely:
1. Drilling mud
2. The preparation
3. Hardware circulation
4. The conditioning of sludge
In general, the drilling mud can be circulated in the following order: sludge in steel mud pit sucked by the pump – pressure pipe – stand pipe – rotary hose – swivel head – kelly – drill pipe – drill collar – bit – annular drill collar – annular drill pipe – mud line / flow line, shale shaker – stainless mud pit – smoked pump back and forth. This can be seen in Figure 4:31.
Figure 4:31. Circulation system
1. Drilling mud is an important factor in drilling. Drilling mud is initially only serves as a carrier powder drill (cutting) from the base of the drill hole to the surface. The drilling mud has important functions in the drilling operations, among others:
– Lifting the cutting surface.
– Controlling the formation pressure.
– Cooling and lubricate the bit and drill string.
– Giving the wall in the drill hole with mud cake.
– Resist cutting when circulation is stopped.
– Reducing the weight of a series of drill pipe portion (bouyancy effect).
– Removing the cutting and sand the surface.
– Get information (mud logging, sample log).
– As media logging.
There are two (2) important in determining the composition of the drilling mud, namely:
– The light and watered a drilling mud, the greater the rate of penetration.
– The heavy and viscous a drilling mud, the easier to control subsurface conditions, such as the inclusion of high-pressure formation fluids (known as “kick”). If this condition can not be resolved will lead to wild bursts (blow out).
2. The preparation placed on the commencement of mud circulation, which is close to the pump mud. Site preparation drilling mud consists of equipment that is set to give a preparation facility or drilling mud treatment. These include site preparation mud house, steel mud pits / tanks, mixing hopper, chemical mixing barrels, water tanks and reserve pit.
