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Wood stabilization limits water absorption into the wood structure, thereby limiting the dimensional changes which arise from moisture exposure. Wood stabilization is a subset of wood preservation processes specifically used by woodworking enthusiasts to alter the material properties of specific wood species for applications within their craft ...
Wood easily degrades without sufficient preservation. Apart from structural wood preservation measures, there are a number of different chemical preservatives and processes (also known as timber treatment, lumber treatment or pressure treatment) that can extend the life of wood, timber, and their associated products, including engineered wood ...
The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.
The term "roughing pump" derives from the vacuum range it works in, "rough vacuum", above 1x10 −3 torr (0.1 Pa). Pumps that operate in the high vacuum ranges typically don't operate, or only operate inefficiently, at atmospheric pressures, whereas pumps that work efficiently at atmospheric pressure usually cannot produce a vacuum lower than ...
The Wood Screw Pump is a low-lift axial-flow drainage pump designed by A. Baldwin Wood in 1913 to cope with the drainage problems of New Orleans. Wood's extremely efficient pumps replaced less efficient pumps in the city's drainage system, prior to which the city had experienced chronic flooding problems, bringing diseases such as malaria and ...
These can become polymer solutions upon curing inside of a wood substrate, imparting stabilizing properties. Impregnation of these resins involves a vacuum chamber procedure that completely disperses the resin into the wood. Once inside of the wood, the resin can diffuse into the cell wall and enhance the physical strength of the wood even ...
These pumps, often submersible and powered by electricity, can access water reserves located much deeper than shallow wells, ensuring a consistent supply even during periods of drought. They include different kinds of pumps, most of them submersible pumps: Hand pump, manually operated; Injector, a jet-driven pump; Mechanical or rotary lobe pump ...
The shoe is generally wider than the caisson to reduce friction, and the leading edge may be supplied with pressurised bentonite slurry, which swells in water, stabilizing settlement by filling depressions and voids. An open caisson may fill with water during sinking. The material is excavated by clamshell excavator bucket on crane. [citation ...