shale shaker working principle!
A shale shaker is a crucial and essential piece of equipment in a drilling fluid solids control system, and its role is crucial. Today, we’ll discuss the principles of screening and how screening works on a drilling fluid shale shaker.
How does a shale shaker screen
During drilling, the fluid returns to the wellhead, carrying cuttings. It flows through a raised trough, then a diverter box. Next, it goes into the logging tank and onto the vibrating screen. This is where solid-liquid separation begins. This separation is a gradual process. Initially, only a small amount of fluid passes through the screen. Most of the liquid stays with the solids, forming a mud layer on the screen’s surface. This mud layer becomes thinner as separation progresses, reaching a certain point. The point where the liquid phase ends is generally called the liquid phase cutoff line. After passing the cutoff line, solid particles continue to advance until they exit the vibrating screen. When the drilling fluid vibrating screen is operating properly, the cutoff line is generally located approximately 2/3 to 3/4 of the effective length of the screen.
The fundamental requirement for drilling fluid shakers in drilling technology is to both remove as much harmful solids as possible and recover as much drilling fluid as possible. The screening process involves both the sieving of the liquid phase and the movement of the solids across the screen. Drilling fluid surrounds the irregularly shaped and sized solid particles (rock fragments or clumps). Even after separation, the solid particles remain wet, still surrounded by the fluid. Therefore, the structure and parameters of the shaker and screen, as well as the properties of the drilling fluid, directly impact the screening process.
When submerged, a slow movement velocity can easily clog the screen, which reduces processing capacity and can even cause slurry leakage and drilling fluid loss. After solid-liquid separation, a slow movement velocity increases the chance of small particles passing through the screen and can even cause solid particles to accumulate on the screen, leading to premature failure due to excessive load.
Solid particles can move in several different ways on the screen surface:
Relative static: Particles and particle clusters remain in contact with the screen and move with the screen surface.
Forward sliding: Particles and particle clusters remain in contact with the screen and move relative to the screen surface toward the discharge outlet.
Reverse sliding: Particles and particle clusters remain in contact with the screen and move relative to the screen surface in the opposite direction toward the discharge outlet.
Throwing angle: Particles and particle clusters are thrown off the screen surface and move in a parabolic trajectory toward the discharge outlet.
Xi’an HL Petroleum Production Shale Shakers offer a variety of models and specifications. Contact us for more information. We guarantee your satisfaction and confidence with our product quality and after-sales service.
