Special design on mud agitators

Mud agitators are the equipment to stir drilling fluids. The drilling fluids are in the active tank, in the reserve tank, and the mixing tank. For all these tanks, we need to fit agitators to maintain drilling mud property and suspend solids properly

Mud agitators design

We all know mud agitators are assembly with gearbox and motor. This part is the power module. Agitator shaft connected with the gearbox output shaft to realize agitation. The shaft speed is the rotation rate of the motor after reduction. That means, agitator shaft or the gearbox shaft speed is a reduced one at a certain ratio

Mud agitators

So when we design the mud agitator, the reduction ratio is an issue to take into consideration. However, how to design it properly? How to select the proper reduction ratio? For example, the motor speed is 1480rpm we need agitator speed to be around 70 rpm, then the gearbox ratio should be 1480/70=21.1:1. Then, how to know we need an agitator speed of 70rpm?

In our previous post, there is professional information about agitator sizing. Including how to calculate TOR. It’s related to tank size, mud property. The easy and simple way to get proper design agitator is by referring to existing guidance drawn by professionals. We can ask the manufacturer or the supplier of agitators.

Besides the design of agitator speed, there are designs on different components. Such as motor features, do we need a motor with an invertor or not, do we need an explosion proof motor or not, do we need a right angle style or a vertical style. For the gearbox, do we need a worm wheel and worm rod or a helical bevel gearbox?

Above information is the part of power module. Further information of below is regarding the shaft and impeller.

Shaft and impeller design of mud mixers

For the shafts, we consider the length, diameter, connection way, elevating type or not. The length of shaft defines by tank depth, and client’s requirement. Usually, it’s 3” higher above the tank bottom.

Worm and wheel geared agitators

Regards to the connection, we can mount impeller shaft to gearbox output shaft by bolts and coupling. Of course, the coupling type is more stable and reliable. However, such design costs higher.

At the end of shaft connecting to impeller, we can weld them together or use the bolts to mount impeller and bush out of shaft. There 2 options, one is impeller is an assembly, the other one is impeller blade can be mounted to a common plate when user need.

For both of the options, we can put impeller centre circle on shaft bushing by bolts. If user requests elevating impeller, we’ll design the impeller shaft with pin hole to hold the certain level impeller by retaining centre circle.

About the impellers. There are canted blades, vertical blades, and the blades with winkle or corrugation. Some clients request rather special design, such as general style of impeller like a fun impeller or a positive triangle. Of course, such design is according to actual working condition, too.

What factors will affect mud agitators design?

Just now, we have talked many about agitators design. Do you have any comments? During your operation, selection, sizing or purchase on mud agitators, if you faced any problem? How do you solve them?

In daily selection of agitators, we usually consider motor power, shaft length, other information is given by supplier or manufacturer. Only if you have a very specific requirements, such as replacing existing one, otherwise, just tell supplier the working condition you’ll get a proper agitator.

Yes, you are right. The supplier you selected must be professional enough. No matter how, the more details you give to suppliers the more proper equipment you will get. Finally, no matter how to design agitator, its quality and performance is the essential factor to evaluate it.

Please feel free to contact AIPU solids control for your optimal solutions.