Matching and Using of Solids Control Equipment
During drilling,the drilling bit cutting、crushing and grinding stratum to break the rocks,the size of different cuttings is between 2-2×10³μm.
Form 1 lists the application scope of different solids control equipment.In order to insure bringing the cuttings deep inside the well back to the ground,the drilling fluid must satisfy enough up-hole velocity.Therefore,the displacement of a drilling pump is up to well diameter and drill capacity.Choosing solids control equipments must take both purification level and handling capacity into consideration.
Selection of Shale shaker
Shale shaker is the primary processing equipment in solids control system used for separating larger cuttings from drilling mud, and must be used all over the whole drilling process.The size of solid particles separated by a shale shaker is decided by the specification of its shaker screen. The screen mesh is larger, the handling capacity is smaller and vice versa.For production,the denser the mesh of shaker screen the better;but for economy,the fine-mesh screen is not durable.Mechanical laminated screen and chemical bonding type laminated screen can effectively extend the service life of fine-mesh screen and purification level of drilling fluid shale shaker.
Solid Particle Classification
Solid Particle Weight Content/%
Corresponding control Equipment
Fine shale shaker or desander
Ultra Small Hydrocyclone or Centrifuge
By this way,we can conclude an economic method of using shaker screen.In the beginning of drilling, the well diameter is big so does the displacement of pump,the ROP is high and produces more cuttings and the cuttings are larger in size,so fine-mesh screen should be applied to handle the drilling fluid.With the depth of well increases,the well diameter becomes smaller so does the displacement of pump,the ROP becomes low and produces less cuttings and the cuttings are smaller in size,so larger mesh screen should be used to handle the drilling fluid.