Flash butt welding, Mechanical Engineering

Assignment Help:

Flash Butt Welding

The two pieces to be welded are pressed against each other by applying a pressure. To whatever finish the faces are machined, there will be some protuberances which cause contacts. Because of the bridges present, when a high welding current is passed, a high current density results at the contact surface. The bridges get heated upto molten conditions since one work piece is slowly advancing towards the other. After the faces attain a plastic stage upsetting pressure is applied. The molten metal and some of the impurities associated with it are expelled. Depending on the material and contact area preheating and post heating may be warranted.

A typical flash butt welding sequence will comprise the following steps. Load machine - clamp work - apply preheating force - preheat - Release preheat force to separate work pieces Contact Contact parts lightly for flashing - apply welding voltage - Flash at high voltage Flash at normal voltage - Cut off welding current - pass up set current - Upset - Cut off upset current - Reclamp and post heat - Pinch off and shear die operation Unclamp work - Return platen and unload.


Related Discussions:- Flash butt welding

Question, A28) cm diameter pipe carries oil of sp. gr. 0.9 at a velocity of...

A28) cm diameter pipe carries oil of sp. gr. 0.9 at a velocity of 3 m/s . At another section diameter is 20 cm. find the velocity at this section and also mass rate of flow of oil.

Stages in making a spot welding, Q.Show the procedure of spot welding ? ...

Q.Show the procedure of spot welding ? The steps involved in making a spot weld are listed below and shown but before spot welding one must make sure that (i) The job is clea

Determine the reactions at beam, Determine the reactions at bea: A can...

Determine the reactions at bea: A cantilever AB, 1.8 m long is fixed at A and carries uniformly distributed load of 20 kN/m over its entire length and a point load of 30 kN at

FEA, Consider the rocket on a test stand as described in Chapter 3 of the l...

Consider the rocket on a test stand as described in Chapter 3 of the lecture notes. The nose of the rocket is fixed. The rocket is of length L, constant EA and constant m, mass per

Hydro turbine, in hydro turbine vaccum is present in casing or not? & if no...

in hydro turbine vaccum is present in casing or not? & if not then how suction is take place?

Assignment, Which chromium plating is more eco-friendly - trivalent or Hexa...

Which chromium plating is more eco-friendly - trivalent or Hexavalent? Justify your answer in the light of environmental issues caused.

Line of action of force, Line of action of force: Sol.: The directio...

Line of action of force: Sol.: The direction of force along the straight line through its point of application, in which force tends to move body to which it is applied. Thi

Define pattern colour code, Q. Define pattern colour code? The patterns...

Q. Define pattern colour code? The patterns are normally painted with contrasting colours such that the mould maker would be able to understand the functions clearly. The colou

Hot pressing-manufacturing methods of ceramics, Hot Pressing This pres...

Hot Pressing This pressing requires application of pressure throughout sintering. In usual understanding hot pressing comprises in applying a unidirectional pressure via the a

Solve equations using regula-falsi method, a) Determine a root of the equat...

a) Determine a root of the equation x-cosx =0 using Bisection method correct to three decimal places. b) Determine smallest possible root of the equations x-e -x =0 using Regul

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