Poly tetra fluoro ethylene, Civil Engineering

Assignment Help:

Question
Why Poly tetra fluoro ethylene (PTFE) is usually used in sliding bearings?

Answer
The choice of sliding surface of bearings is of very important importance since sliding surfaces generate frictional forces that are exerted on bearings and substructure of bridge. For example, PTFE and lubricated bronze are usually choices of sliding surfaces for bearings. PTFE is fluro carbon polymer which possesses high-quality chemical resistance and be able to function in wide range of temperature. On whole significant characteristic of this material is its low coefficient of friction. PTFE has slightest possible coefficients of static and dynamic friction of any solid with absence of stick-slip movement by David J. Lee. The coefficient of friction is established to decrease with add to in compressive stress. However, PTFE contain some demerits like high thermal development and low compressive strength.

In designing complementary contact plate with PTFE sliding surface, stainless steel plates are in general selected where plates have to be larger than PTFE surface to let movement without exposing PTFE. Moreover, it is recommended that stainless steel surface be located on top of PTFE surface to avoid contamination of dirt and rubbish. Lubricants are now and then introduced to decrease friction between PTFE surface and upper stainless steel plate. Hence, PTFE might be designed with dimples to keep away from lubricant from squeezing out under repeated conversion movements.


Related Discussions:- Poly tetra fluoro ethylene

What is raft foundation, Q. What is Raft Foundation? A raft or mat is c...

Q. What is Raft Foundation? A raft or mat is combined footing that covers the entire area beneath a structure and supports all the walls and coloumn when the allowable soil pre

What is activated sludge process, Q. What is Activated Sludge process? ...

Q. What is Activated Sludge process? The term Activated Sludge is used to indicate the sludge which is obtained by settling sewage in presence of abundant oxygen. The Activated

What is switch and expansion joint, Q. What is Switch and Expansion Joint? ...

Q. What is Switch and Expansion Joint? Switch Expansion, Joint (SEJ) is an expansion joint installed at each end of LWR/CWR to permit expansion/contraction of the adjoining bre

What is the tensile strength of wood, The tensile strength of a material is...

The tensile strength of a material is the value at which the material fails when subjected to a tensile force. (Tensile means a force pulling the wood fibers lengthwise, as opposed

Case of multi speed restrictions, Q. Case of Multi speed restrictions? ...

Q. Case of Multi speed restrictions? Position of Engineering indicators in case of Multi speed restrictions on one of the line in a Double line section where the first speed re

Explain mild and high-yield steel, High-yield steel vs. mild steel as road ...

High-yield steel vs. mild steel as road reinforcement High yield steel is the preferred material for the reinforcement of concrete carriageway due to the subsequent reasons:

Accuracy and range - angle measurement, Accuracy and Range - Angle measurem...

Accuracy and Range - Angle measurement: Accuracy and Range:-Angle measurement:-Most modern total station instruments measure angles by means of electro-optical scanning of ext

Pelton wheel, what is the use of the pelton wheel

what is the use of the pelton wheel

Illustrate truss with k-bracing, Q. Illustrate Truss with K-bracing ? I...

Q. Illustrate Truss with K-bracing ? In the arrangement of triangulated framework in truss structures, it's more economical to design longer members as ties whereas shorter one

Bulking of sand, what is the permissible limit of sand

what is the permissible limit of sand

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd