subject: Sieve Shaker And Screen [print this page] A vibratable sieve shaker screen is disclosed which in one aspect, has a frame, screening material secured over the frame, and one or more sealing members secured to the frame for sealingly contacting an adjacent frame and/or adjacent portions of the frame or of screen mounting apparatus such as mount channels on the frame. Alternatively, sealing elements are provided on screen mounting apparatus, e.g. channels, on a sieve shaker. A shale shaker is disclosed with at least one such screen. In one aspect such a shale shaker has three such screens disposed in a tiered configuration, one screen in sealing contact with the next. Adjustable screen mounts are disclosed for releasably holding the screens in sealing contact with each other and with screen mounting apparatus.
the at least one screen comprising three screens disposed end-on-end one next to the other, each screen held in sealing contact with each adjacent screen bysieve shaker screen support means for supporting each screen, and each screen held in sealing contact with screen mounting apparatus in which each screen is mounted, the three screens mounted in tiered fashion with a first highest screen sealingly contacting a second middle screen, the second middle screen positioned at a level below a level of the first highest screen, the second middle screen sealingly contacting a third lowest screen, the second middle screen positioned at a level above a level of the third lowest screens, the screens disposed in end-to-end alignment for the movement of material to be screened initially to the first highest screen, from thence to the second middle screen, and from thence to the third lowest screen,
The prior art discloses a wide variety of vibrating screens, devices which use them, sieve shaker, and screens for shale shakers. In shale shakers which use a plurality of screens, problems are encountered with the leakage of fluid, e.g. mud, between screens and between screens and the edges of screen supporting members. Mud which leaks through these areas is not screened; i.e. an acceptable level of the separation of liquid (e.g. oil) from cuttings or drilling solids is not achieved.
