Oil drilling,solids control and shale shaker

XI'AN, China - May 5, 2016 - PRLog -- O&G drilling procedure

Oil and gas are found in large fields all around the globe and in many places far below sea level. This is the case in for example Norway. To move the oil from the well to the surface, where it can be processed and transported, a drill bit makes a hole through the sea floor to the well. The drill bit penetrates the sea floor and can then be steered in three dimensions to reach the final target. When the well is completed and secured the work is handed over to production which extracts the oil. The drill bit is mounted and operated from a vessel such as a drill ship, semi-submersible or an oil platform

A drill bit is used for the actual drilling and is powered by the circulating fluid and the top- drive rotating the drill string. A drill string consists of long steel tubes connecting the drill bit to the drill ship or oil platform. The drilling fluid or "mud" is pumped down through the drill string and drill bit to facilitate the drilling and remove cuttings. The diameter of the drill bit is larger than the diameter of the drill string creating an area outside of the drill string (annulus). Here the mixture of drilling fluid and cuttings flows upwards along the drill string. The drilling fluid prevents the hole from collapsing and ensures that the wellbore pressure is contained by adjusting the drilling fluid density.

Solids control

During decades practice we found there are so many benefits by controlling solid in drilling fluid or mud. http://www.aipusolidcontrol.com/html/products/solids-cont...

Increased drilling penetration

Increase bit or back reamer life

Reduce mud cost

Reduce triplex mud pump, mud motor & surface equipment maintenance cost.

Reduced clean up & haul off or disposal cost

These benefits are the result of planning prior to boring and are accomplished through the use of properly designed, sized and operated solids removal equipment. It is the responsibility of the boring crew to become knowledgeable in the proper use of the equipment; otherwise the potential benefits may be reduced or nullified.

Methods of Controlling Solids

Mechanical treatment

Chemical treatment

Dilution of mud with water

Discard mud & mix new mud.

All of the above with the exception of Mechanical treatment in most cases are cost prohibitive.

Shale shaker during whole project

Shale shaker is a machine that separates the drilling fluid from cuttings. It does so by letting a bed consisting of a fine metal mesh vibrate while the fluid flows through. The shale shakers come in a variety of sizes from several different brands and therefore there is a great variety of the shape and size of the shaker screens. Except for the outer size there is also different shaker screen mesh with different thread thickness, size of holes and shape. It is important to have the correct hole size to minimize the fluid waste. If the mesh holes are too big, particles will not be removed from the fluid resulting in increased wear on hoses and tools. If the mesh holes on the other hand are too small, the mesh risks of being clogged quickly making the valuable fluid stick to the cuttings and being thrown away. There are also shaker screens that are flat and those with a three dimensional pattern such as pyramid shapes going along the full length of the shaker screen. The pyramid shape increases the mesh area without affecting the outer dimensions of the shaker screen why these are becoming more and more popular

When the drilling fluid reaches the drilling vessel it is divided onto a number of shale shakers (typically 4-8 units, mounted in parallel), separating the cuttings from the fluid. There are usually between six to eight shaker screens per shale shaker. The drilling fluid is then reused. The shale shakers are stacked closely together in one room, and if there are any shaker screen cleaners there is one or two located nearby. There is often just enough room for an operator to pass between the shale shakers and the wall. The operators spend as little time as possible in the shaker room due to high noise levels and exposure to hazardous gases and vapors