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

What is the brick inner surface temperature, Derive 3-D non-steady state co...

Derive 3-D non-steady state conduction equation in spherical co-ordinates. Explain the assumption involved. The hot combustion gases of a furnance are divided from the ambient a

Sleepers - permanent way, Sleepers: The sleeper is the part of the tr...

Sleepers: The sleeper is the part of the track on which the rails rest. Its functions are : (a) To hold the rails to the correct gauge. (b) To transmit and distribute t

State the planning the foundation for reciprocating engines, State the Plan...

State the Planning the foundation for reciprocating engines i)  The eccentricity of  the common centre of gravity of machine and foundation referred to the centroid of base are

Explain Machining allowance, Can you show us - Overall length of external s...

Can you show us - Overall length of external surfaces, cm In image Material Cast Overall length of external surfaces, cm 0 to 30 30 to 60 60 to 105 1

What is air intakes, Q. What is Air Intakes? Air is drawn from the atmo...

Q. What is Air Intakes? Air is drawn from the atmosphere for a variety of process and equipment uses, including: • Combustion air (fired heaters, boilers, gas turbines, int

Theory of production process, In Grey Cast Iron, carbon is present in -----...

In Grey Cast Iron, carbon is present in ------------form while in white cast iron, it is found in ----------- form.

Inlet manifold-basic components of engine , Inlet Manifold: The pipe whic...

Inlet Manifold: The pipe which connects the intake system to the inlet valve of the engine through which air or air-fuel mixture is drawn into the cylinder is called the inlet ma

Mechanical properties of materials, A tensile test on a specimen having an ...

A tensile test on a specimen having an initial diameter of 13.11 mm and an initial gauge length of 200.0 mm, gave the following data:

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