When configure or increase drilling mud total volume to change drilling mud density, viscosity, loss water, etc. We need to put drilling mud materials and corresponding chemical additives into mud tank. If directly put them into tank will lead to drilling mud materials and chemical additives forming lots of sediment, we can’t obtain disperse and steady drilling mud. Especially in an emergency case of possible blowout need to evenly mix and configure lots of weighted materials in the shortest time, so we must utilize accessory equipment to finish, which is called jet mixing pump. Mixing pump is a kind of equipment that is used as supporting equipment in the solid control system of oil drilling to meet drilling mud weighted and configuration
Jet mixing pump is usually composed of one set of centrifugal pump and a set of jet mixing hopper, which is connected by pipe manifold valve to install on single jet mixing device that is composed of a base. Or two sets of pumps and two sets of mixing hopper composed a double jet mixing pump.
Generally speaking, if want to enhance treating capacity, we can depend on increasing work pressure and changing a larger spray nozzle to realize. And experiments show that increasing the nozzle diameter and inlet flow rate is a more economical method.
Main factors affecting on jet mixing pump performance
1. Reduce hydraulic edge of mixing hopper loss as far as possible, or may lower treating capacity greatly.
2. The distance from pray nozzle to venturi tube should be suitable, the best distance is to keep at 32-90mm, usually can’t exceed 90mm, otherwise, the feeding speed of barite will be decreased significantly.
3. The back pressure of the outlet pipe should be suitable, the larger back pressure will reduce the processing capacity of the mixing hopper.
For example, when the nozzle outlet diameter is 50mm, the gap between the nozzle and the venturi tube is 90mm and the working pressure head of the mixing hopper is 21-23m. The mixing chamber has a high vacuum value before the pressure value is reached 50%. But when back pressure close to the inlet pressure 50%, the vacuum degree is almost zero and drilling fluid start back-flow in the hopper.
4. The larger inlet pressure, the larger treating capacity of mixing hopper.
5. The higher for mixing hopper installation, the higher back pressure and mixing ability will be decreased.
