Analysis of screening rate of drilling fluid shaker
Release time: 2015/10/28 Ai Yi NewsViews : 1479
A well-equipped drilling fluid vibrating screen with excellent technology, good penetration rate and easy operation is not enough. A vibrator is an important factor affecting the vibrating screen's exciting force and intensity. The drilling fluid vibrating screen is ideal for operation, and it requires a proper installation method for worry-free, trouble-free, and comfortable drilling fluid shakers, so that the vibrator can exert its maximum effect and prolong the use time of the vibrator. Linear vibrating screens are generally installed horizontally, so only by giving a certain vibration inclination angle, that is, the angle between the line of action of the combined force of the two shakers and the horizontal plane (screen surface), the material on the screen surface can move forward. (Small materials with small vibration inclination angle go fast, otherwise they are slow).
The material on the sieve surface jumps along this direction, and then falls under the action of gravity. With the continuous rotation of the shaker, the material continues to jump and sneak on the sieve surface, and the material smaller than the mesh size of the sieve surface continuously drops; The material larger than the mesh size is discharged from the sieve surface, so that the screening and transportation of the material are completed at the same time.
During the working process, the circular drilling fluid vibrating screen is similar to the linear drilling fluid vibrating screen. (The circular drilling fluid vibrating screen is generally installed at an oblique direction.) The screen surface of the circular vibrating screen is a circular motion trajectory. Constantly turning and loosening, so the fine particles in the material are easy to move to the lower part of the material layer, which increases the chance of contacting the screen surface and timely discharge through the screen holes. In addition, the material stuck in the mesh is easy to jump out, reducing mesh blocking.
The working process of a vibrating screen is the process of sieving and conveying materials. A good vibrating screen needs to be sieved much and clean. It is the hope of our users. That is, the processing capacity is large, and the screening efficiency is also high. The so-called sieving efficiency refers to the ratio of the actual sieving material (the material passing through the sieve hole) to the mass of the sieving material (theoretical sieving material) contained in the feed. In theory, all the materials smaller than the mesh in the feed should pass through the screen, but in fact, due to various reasons, such as the connection between the manufacturing process of the screen box and the screen, only a part of the fine materials can pass through. The sieve holes are discharged, and the rest is contained in the sieve, so the screening efficiency of the drilling fluid vibrating screen is always less than 1.
There are many factors affecting the sieving of materials. First of all, from the perspective of the material itself, there are high and low water content, good and bad fluidity, the shape of the material particles, and the particle distribution. Generally speaking, materials with small water content (referring to a certain range of water content), good fluidity, regular particle shape, and smooth edges without edges are easier to pass through the sieve. Secondly, from the perspective of screening equipment, its structural form, vibration frequency and amplitude, screen structure and effective screening area are all major factors affecting screening efficiency.
For difficult materials and fine materials (or in order to improve the screening efficiency), we can appropriately increase the tilt angle of the vibration and reduce the angle of the screen facing downward (both methods can slow down the speed of the material), circular drilling fluid The vibrating screen can adjust the rotation direction of the vibrator (rotating against the flow of the material) to extend the contact time between the material and the screen surface to facilitate penetration of the screen, but the processing capacity will be relatively reduced. For large particles and easy-to-screen materials, you can reduce the tilt angle of the vibration and increase the angle of the screen's downward tilt to increase the speed of material flow to increase production.
This is the special feature of the screening machine. It must not only achieve a certain amount of processing capacity, but also have screening efficiency. These two are a contradictory set. A vibrating screen that does not consider the screening efficiency is no different from a conveyor and is meaningless. We should properly select the processing capacity and screening efficiency in a scientific manner based on actual conditions and existing conditions to meet the needs of users as much as possible.
Considering that the material under the sieve is larger than the mesh size, sometimes the concept of sieving is used.