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

Thermodynamics, What are significnces of quasi static process

What are significnces of quasi static process

Assignment , assignment on the topics of preservation of safety & accident

assignment on the topics of preservation of safety & accident

What is the specific weight of the timber, (Buoyancy; force & moment balanc...

(Buoyancy; force & moment balance) A partially submerged, homogeneous timber is 0.15m by 0.35m in cross-section. What is the specific weight of the timber and the tension in the r

Determine the wire diameter of the inner spring, Determine the wire diamete...

Determine the wire diameter of the inner spring: In a compound helical spring, the inner spring is arranged in and concentric with the outer one, but is 10 mm shorter. The out

GOVERNORS, Explain Wilson HArtnell Governor

Explain Wilson HArtnell Governor

Determine the maximum shear stress and angle of twist, Determine the maximu...

Determine the maximum shear stress and angle of twist: A hollow circular shaft of 6 m length and inner & outer diameter ois equal to 80 mm and 100 mm is subjected to a torq

Evaluate the least pull, Evaluate the least pull, through the center of whe...

Evaluate the least pull, through the center of wheel: A uniform wheel having 600 mm diameter, weighing 5KN rests against rigid rectangular block of 150mm height as shown in t

How is bearing capacity of soil varied, How is bearing capacity of soil var...

How is bearing capacity of soil varied? The bearing capacity of soil varies not only with its strength but also with the magnitude and distribution of the load. When a load Q,

Bending stresses, Determine: Reaction forces at the supports The shear an...

Determine: Reaction forces at the supports The shear and moment diagrams The location and value of the maximum shear and moment The cross section is an angle section as given in

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