A slide plate is a

linear bearing A linear-motion bearing or linear slide is a Bearing (mechanical), bearing designed to provide free motion in one direction. There are many different types of linear motion bearings. Motorized linear slides such as machine slides, X-Y tables, ro ...

that may be part of the

expansion joint A expansion joint, or movement joint, is an assembly designed to hold parts together while safely absorbing temperature-induced expansion and contraction of building materials. They are commonly found between sections of buildings, bridges, s ...

s of

bridge A bridge is a structure built to Span (engineering), span a physical obstacle (such as a body of water, valley, road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, whi ...

s, high temperature horizontal ducts of

water-tube boiler A high pressure watertube boiler (also spelled water-tube and water tube) is a type of boiler in which water circulates in tubes heated externally by fire. Fuel is burned inside the furnace, creating hot gas which boils water in the steam-generat ...

s and other

mechanical Mechanical may refer to: Machine * Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement * Mechanical calculator, a device used to perform the basic operations o ...

structural engineering Structural engineering is a sub-discipline of civil engineering in which structural engineers are trained to design the 'bones and joints' that create the form and shape of human-made Structure#Load-bearing, structures. Structural engineers also ...

applications. In each case one plate is fixed and the other slides on top as expansion or contraction occurs. The plates provide a surface with a low

coefficient of friction Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of t ...

which can be attached to a supporting structure. This combination provides support while simultaneously allowing an object to move (slide) freely along the supporting surface. The plate may be of

polytetrafluoroethylene Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene, and has numerous applications because it is chemically inert. The commonly known brand name of PTFE-based composition is Teflon by Chemours, a corporate spin-of ...

(PTFE),TEF-MET, Lubrite or

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

according to the application. Multiple design variations are possible but the most common example of a slide plate (in structural applications) has glass-filled PTFE bonded to a steel backing plate. In these applications a two-part system is used which has an upper element with stainless steel surface face-down and bearing on a lower element with its PTFE steel backing surface face-up. In most applications, the upper element is larger than the lower element by the amount of movement expected. This has a two-fold advantage of maintaining a constant bearing area and preventing the lower surface from being exposed to dirt, grit or other contaminants throughout the range of motion. Slides plates are arranged in a 'sandwich' formation, which is made of an upper slide plate and a lower slide plate component. Commonly used in * Oil/gas/chemical industries * Complex steel structures * Post-tensioned concrete structures

References

Bearings (mechanical) Bridge components {{civil-engineering-stub

See also

References