Negative pressure vibrating screen will run out of slurry during field use. This phenomenon occurs in negative pressure vibrating screen, which is mainly related to factors such as high solid content in drilling fluid, high mud viscosity, and dispersion of drill cuttings. The vibration force of the negative pressure vibrating screen is small, the mesh number of the screen is high, and the screen area is small.

1: The selection of the mesh of the negative pressure vibrating screen is unreasonable. The negative pressure vibrating screen cannot use a finer screen in the shallow well section. When drilling, a larger screen should be used. With the gradual increase of the drilling depth, The screen should also gradually adopt a finer screen.
2: During the working process of the negative pressure vibrating screen, the formation and mud conditions affect the treatment capacity. Because the drugs added in the drilling fluid are not fully dissolved, they are stuck on the screen, and the phenomenon of serious slurry running will occur at this time. It should be used after the drug is fully dissolved, or a larger mesh screen should be used. On the other hand, when drilling into a loose sandstone-bearing layer or quicksand layer, the sand particles are easily stuck in the screen holes, resulting in the phenomenon of screen blocking. Therefore, it is necessary to test several screens of different mesh numbers to reduce the phenomenon of screen blocking.
3: Before the negative pressure vibrating screen works, check whether the steering of the motor is correct. If the steering is wrong, please replace any two phase wires in the incoming power supply of the electric control box. Wrong way 1: The two vibrating screen motors rotate inward, although they can also remove drill cuttings, but the speed is slow; Wrong way 2: The two motors rotate in the same direction, the vibration force is very small, and they basically do not discharge sand or deal with mud.