What are the types of drilling mud agitators? Let’s first understand the classification method of mud agitators. Mud agitators can be classified according to different reducer motor connection methods, different impeller structures, different mixing media, and different uses. Different classifications have different types of agitators. According to the connection mode of the reducer, it can be divided into turbine type and helical gear type; according to the structure of the impeller, it is divided into flat blade, folded blade, and spiral blade mud agitator. According to the fluid flow, it is divided into axial flow, radial flow, and mixing. Flow mud agitator, divided into low-viscosity fluid and high-viscosity fluid mud agitator according to purpose.
The mud agitator is divided into turbine type, propeller type and paddle type according to the different fluid flow direction.
Turbine mud agitator
Turbine mud agitator is the most commonly used type of agitator in the drilling fluid mixing process. It can effectively complete almost all mixing operations and can handle fluids with a wide range of viscosities. It belongs to agitators for low-viscosity fluids. Turbine agitators can be divided into two types: open type and disc type. The open type has flat straight blades, oblique blades, curved blades, etc., and the disc type has disc flat straight blades, disc oblique blades, disc curved blades, etc. The number of blades commonly used in open turbines is 2 blades and 4 blades, and the disk type is the most common with 6 blades. The turbine agitator has a large shear force, which can make the fluid clusters dispersed very finely, and is suitable for mixing, liquid-liquid dispersion, and liquid-solid suspension of fluids with low to medium viscosity. The straight blade has a great shearing effect, which is a shearing type agitator. Curved blade means that the blade is bent in the direction of flow, which can reduce power consumption and is suitable for mixing fluid containing fragile solid particles.
Propeller mud agitator
The standard propeller agitator has three blades, the pitch of which is equal to the diameter of the paddle. The degree of turbulence of the fluid is not high when the propeller blade is stirring, but the circulation volume is large. The propeller blade has a simple structure and is convenient to manufacture. It is often used in low viscosity fluids. It is suitable for occasions with low viscosity and large flow. It has good circulation performance and little shearing effect. Belongs to the circulation type agitator. The diameter of the propeller agitator is small, d/D=1/4-1/3, and the tip speed is generally 7-10m/s, up to 15m/s.
Paddle mud agitator
The blades are made of flat steel and are fixed on the hub by welding or bolts. The number of blades is 2, 3 or 4. The blades can be divided into two types: straight blades and hinged blades. Paddle agitators are mainly used for fluid circulation. Since the folded blade type has less power consumption than the flat blade type under the same displacement, the axial flow blades are used more. The so-called axial flow blade means that the main liquid discharge direction of the blade is parallel to the stirring axis. Paddle agitators can also be used to stir high-viscosity fluids to promote the up and down exchange of fluids, instead of expensive ribbon impellers. The speed of the paddle agitator is generally 20-100r/min, and the maximum viscosity is 20Pa.s.
The above is the difference between the turbine type, the propeller type, the paddle type and the 3 types of mud agitators. In addition to these three types, there are many types of mud agitators. The mud agitators currently used in oilfield drilling solids control are mainly turbine type.