Screening media for screening material includes a main body and a plurality of openings extending through the main body between a contact face and back face. The openings are of a shape of a convex and non-regular polygon, and are arranged in an orientation such that a line through the most proximal vertex of the polygon and parallel to a defined material flow direction divides the most proximal interior angle of the polygon. Such a configuration allows the openings to not easily get pegged and to improve screening performance.

A base supports an inclined screen having a uniform mesh selected to remove larger aggregate from a first cement mixture to form a second cement mixture that passes through the screen. A powered vibrator vibrates the screen to separate the concrete mixtures and larger aggregate. Springs and/or dampers in support legs isolate the vibrating screen from the base. A guide frame on the top surface of the screen guides the first concrete mixture along the screen and guide the separated aggregate out a bottom opening into an aggregate container. A support frame on the bottom surface of the screen stiffens the screen to help support the weight of the concrete. A concrete container, preferably wheeled, is below the screen to collect the second concrete mixture and move it to its use location.

A sieve system includes a sieve for screening material by selectively passing first particles and not passing second particles of the material based on respective dimensions of the particles relative to dimensions of screening apertures in the sieve. A holding container feeds material to the sieve and a fines container receives the first particles screened by the sieve. A first fines container load is measured at a first time, and a second fines container load is measured at a second time. A fines rate is determined by a rate of change of the fines container load based on the measured first and second fines container loads and the first and second times. An operating condition of the sieve system is based on the fines rate and may provide an indication that the operation of the sieve, another component, or the sieve system as a whole is acceptable or unacceptable.

A sieving apparatus for separating insect pupa is described. In an example, the sieving apparatus includes a sieving device attached to an actuation system. The sieving device includes a set of openings sized to correspond to a cross-sectional cephalothorax width of a representative pupa of a population of insect pupae to be separated. The actuation system is configured to move the sieving device in a manner that causes smaller insect pupae to pass through the set of openings. Larger insect pupae remain within the sieving device. Such movement can include moving the sieving device with respect to a liquid held in a basin of the sieving apparatus.

A sieving apparatus for separating insect pupa is described. In an example, the sieving apparatus includes a sieving device attached to an actuation system. The sieving device includes a set of openings sized to correspond to a cross-sectional cephalothorax width of a representative pupa of a population of insect pupae to be separated. The actuation system is configured to move the sieving device in a manner that causes smaller insect pupae to pass through the set of openings. Larger insect pupae remain within the sieving device. Such movement can include moving the sieving device with respect to a liquid held in a basin of the sieving apparatus.

A self-cleaning woven wire screening or screen for classifying material. The screening includes a plurality interwoven warp and weft wires forming a plurality of openings in a screen section through which materials to be classified can pass through. The weft wires are preferably configured so that the high points or raised knuckles of the weft wires have a larger diameter, cross-sectional height or thickness than previously possible. Preferably, one or more of weft wires have a configuration that prolongs operational life of the screen or screening and obviates the need for protective encasement blocks (e.g., polyurethane encasement blocks) encasing the weft wires.

A system for separating components from a slurry of drilling fluid and drill cuttings on a shaker screen having an upper side and a lower side within a shaker. The system also has a pressure differential generator to pull an effective volume of air through a section of the shaker screen to enhance the flow of drilling fluid through the section of the shaker screen and the separation of drilling fluid from drill cuttings and further maintain an effective flow of drill cuttings off the shaker. A method of separating components of a slurry of drilling fluids and solids has the steps of delivering the slurry to a shaker, flowing the slurry over a first screen and applying an effective amount of vacuum to a first portion of the first screen to remove the drilling fluids from the slurry without stalling the solids on the first screen.

A system for separating components from a slurry of drilling fluid and drill cuttings on a shaker screen having an upper side and a lower side within a shaker. The system also has a pressure differential generator to pull an effective volume of air through a section of the shaker screen to enhance the flow of drilling fluid through the section of the shaker screen and the separation of drilling fluid from drill cuttings and further maintain an effective flow of drill cuttings off the shaker. A method of separating components of a slurry of drilling fluids and solids has the steps of delivering the slurry to a shaker, flowing the slurry over a first screen and applying an effective amount of vacuum to a first portion of the first screen to remove the drilling fluids from the slurry without stalling the solids on the first screen.

Thermoplastic polyurethane (TPU) compositions, methods for producing TPU compositions, methods of using TPU compositions, and apparatuses produced therefrom are disclosed. Disclosed TPU compositions include a thermoplastic polyurethane polymer, a heat stabilizer, a flow agent, and a filler material. The filler may be a glass fiber. Disclosed TPU compositions have improved thermal stability and improved flow properties suitable for injection molding of articles of manufacture having a large plurality of fine openings or pores. Articles produced from the composition have superior thermal stability, abrasion resistance, and chemical resistance. Example articles include screening members for vibratory screening machines. Further embodiments include compositions without heat stabilizers, flow agents, and filler materials, and compositions in which two TPU materials having different harnesses are combined to generate a material with a pre-determined hardness. Injection molded screen elements having openings from 25 to 150 microns and open screening area from 10% to 35% are disclosed.

A modular, pre-tensioned, self-cleaning screening panel having a frame and at least one pre-tensioned wire that is fastened to the frame.