Weld preparation-joint tolerance-cleaning, Mechanical Engineering

Assignment Help:

WELD PREPARATION: Joint Tolerance & Cleaning

 

Joint Tolerance


The allowable tolerance of joint dimensions depends upon whether the welding is to be done manually or by mechanised means. Manual welding applications can tolerate greater irregularities in joint fit up than mechanised welding. The particulartolerance of a given application can be determined only by actual testing, and this tolerance should be specified for future work.


Cleaning


Cleanliness of both the weld joint areas and the filler metal is an important consideration when welding with the gas tungsten arc process. Oil, marking crayon,grease, shop dirt, paint,  & rust or corrosion deposits all must be removed from the joint edges and metal surfaces, to a distance beyond the heat affected area. Their presence during welding might  lead toarc instability and contaminated welds containing pores, cracks and inclusions. Cleaning may be accomplished by mechanical means, by the use of vapour or liquid cleaners, or by a combination of these. Organic solvents like carbon tetrachloride should not be used as any trace of it coming under the arc may lead to the formation of phosgene, a toxic gas. Acetone may be used. 


Related Discussions:- Weld preparation-joint tolerance-cleaning

Different types of constrained motions, (a) Illustrate with examples the di...

(a) Illustrate with examples the different types of constrained motions ? (b) Describe in detail the following Mechanism : (i) Single slider crank chain mechanism (ii) Fou

Explain the newer machining processes, Explain the Newer Machining Processe...

Explain the Newer Machining Processes In recent years a number of new material have been developed which are being commonly used in space research missiles and nuclear indu

Welding, what is blow hole defect ?

what is blow hole defect ?

First law- closed system undergoing change of state, First Law for Closed S...

First Law for Closed System Undergoing Change of State - thermodynamics: In accordance to first law, when system undergoes a thermodynamic process (change of state) heat and w

Determine the elongation of plate, Determine the elongation of plate: ...

Determine the elongation of plate: Q: A steel bar AB which is having uniform thickness 2 cm, tapers from 1.5 cm to 7.5 cm uniformly in a length of 50 cm. From 1 st principle

Principals, do you know the grade to the answers of the questions in the pr...

do you know the grade to the answers of the questions in the pre paid solutions..?? and what if the answers are wrong..?? as i need all working out shown

Newton law of motion - second law, Newton law of motion: Secon d Law...

Newton law of motion: Secon d Law The rate of change of momentum is proportional to external force applied on the body and take place, in the same direction in which the

Drum brake-types of brake , Drum Brake: The construction of drum brake is...

Drum Brake: The construction of drum brake is clearly shown in Figure 2.40. In a rotating brake drum stationary brake shoes are attached concentric to the axle hub. A back plate

Determine the air standard efficiency, Compare the efficiency of Diesel, ot...

Compare the efficiency of Diesel, otto and Dual combustion cycle on the basis of same compression ratio and same heat input. In an otto cycle air at 17 o c and 1 bar is compressed

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