Operating instruction of shear pump and jet mud mixer

High quality drilling fluid is not composed of one or two materials (such as bentonite) . To keep the capability of the drilling fluids, it needs to add various treatment agent, such as drilling fluid lubricant, high temperature stabilizer, anti-sloughing agent.
According to the statistics in the year of 1992 , treatment agent series has increased to ten categories including 202 kinds, forming an important branch of oilfield chemistry. So the cost of drilling fluid is pretty high. To save the cost of drilling, we need shear pump and jet mud mixer to make up used drilling fluid for periodic duty.
Shear pump is used to effectively mix and hydrate material added into drilling fluid. With large capacity, high lift, and long reliable service life, the shear pump can speed up dilution and hydration of polymers to have property mud. In drilling fluid recycling system, shear pump is very important solids control equipment.

In use process of shear pump, we should notice some details:
1. After using shear pump, we should use clear water flush pipeline and shear pump, to avoid leftover block runner and nozzle of impeller.
2. Bearing bore is filled in grease about 10~20ml every other week, combination seal cavity is filled in grease about 10~20ml every day.
3. In winter, if the pump will not used for a long time, drilling fluid in pump shell should be discharged, to avoid drilling fluid freeze.
At the same time, jet mud mixer is used to make and mix drilling fluid to change the density and viscosity. This device can satisfy the fluid weighting and mixing of solids control system for 1500m-9000m drilling.

In use process of jet mud mixer, we also should notice some details:
1. General requirements mixing hopper capacity shall not be less than 150m3/h. For the larger tank and great pump motor power, we can also use the mixing hopper with 300m3/h capacity.
In order to ensure the required well pressure, suggest that each drilling crew should equipped with a spare set of mixing hoppers, in most cases spare hoppers used overlap mode.
2. The return pressure of outlet pipe needed moderate, overlarge return pressure will reduce the treating capacity of mixed hopper.
3. The gap between nozzle and venturi tube must be suitable, when reach optimum efficiency, the gap is 32~90mm, usually don’t more than 90 mm, otherwise the feed speed of barite will be significantly reduced.

4. Another important consideration of install equipment is the drilling fluid required lifted height. If discharge needed to enter into different deck tank or a taunt tank and hopper, mix rate will be decreased. When the height from 1.83m to 3.66m, barite adding rate will be reduced to 17%. If the increased demand is very high, the pump capacity is insufficient, mixed ability will be greatly reduced.