Welder performance qualifications, Mechanical Engineering

Assignment Help:

WELDER PERFORMANCE QUALIFICATIONS


Requirement of Welder Qualification

In performance qualification, the basic attempt is to establish the ability of the welder to deposit sound metal. In case of welding operator qualification it is his mechanical ability to operate the welding machine that is tested and acknowledged.

During welder's qualification, only the essential variables (as applicable to welder's skill) are considered and production welds with such altered variables should not be continued without additionally qualifying the welders. A welding machine operator usually gets qualified along with procedure test. Additional qualifications are to be suitably enforced as and when certain essential variables are not meeting.

Codes for Performance Qualifications and Acceptance of Defects


A large number of industrial codes now a days recognise prequalified welding procedures as t he manufacturing firms are able to produce the documentary evidence for such procedures as in vogue in their organisations. The selection, training and qualification of welders are the next few steps. Some of the popular codes to look for, at this juncture are:

  • Indian Boiler Regulations - IBR
  • ASME Boiler and Pressure Vessel Code - Section IX (Welding, Brazing & Soldering Qualifications)
  • DIN 8560 - (Testing of Welders)
  • BS 4872 - (Approval Testing of Welders when welding procedure approval is not required.
  • ISO
  • EN

 


There are also number of other specifications for welder testing, pertaining to individual codes of construction. A welder's plate test coupon can be maximum 300 mm x 400 mm with appropriate thickness to cover the allowed, specified thickness ranges. Similarly 2 pipes (or tubes) having a maximum of 125 mm length each are joined together for a pipe weld test coupon.

The test coupons are then subjected to radiography testing. Welders are outrightly failed for the following indications in the radiographic film. All other defects are acceptable within limits.

1. Severe root porosites / blow holes
2. Cluster of porosites
3. Cracks
4. Lack of fusion / incomplete penetration

After necessary post weld heat treatment the plates or pipes are marked, stamped, cut and machined into mechanical test specimens. Though, the requirements of the codes are slightly varied, 2 face bend tests and 2 root bend t ests alone are conducted for performance qualifications. In lieu of the above a radiographic evaluation is done.


Related Discussions:- Welder performance qualifications

Wheels of motorcycle, Wheels:  The wheel, along with the tyre has to take ...

Wheels:  The wheel, along with the tyre has to take the vehicle load, provide a cushioning effect (to protect against force or shock) and cope with the steering control. The wheel

What is a pneumatic system?, Pneumatic system is a system that uses air to ...

Pneumatic system is a system that uses air to power something. For example, have you seen the tube systems at bank drive-up tellers? Air is used to drive the tubes back and forth f

What do you mean by compression moulding, Q. What do you mean by Compressio...

Q. What do you mean by Compression moulding? In compression molding, a material normally in power or perform shape , is loaded directly into the hot die cavity, pressure from

Determine maximum internal diameter of hollow shaft, Determine maximum inte...

Determine maximum internal diameter of hollow shaft: A solid shaft of mild steel which is 200 mm in diameter is to be replaced by hollow shaft of alloy steel for which the al

Calculate the depth of water, (Buoyancy of a submerged body; compressibilit...

(Buoyancy of a submerged body; compressibility of air) A grade 4 science student inverts a cup full of air into a water tank. If it takes 1 lb of force to hold the cup down 3

Resolution of a force - mechanics, Resolution of a force: Sol.: When...

Resolution of a force: Sol.: When a force is resolved into two parts along the two mutually perpendicular directions, without changing the effects of it on the body, the par

Determine the temperature distribution, The wall shown is 1 m thick. The le...

The wall shown is 1 m thick. The left surface of the wall (x=0) is maintained at a constant temperature 200 degrees Celsius. The right surface (x=L=1 m) is insulated. The thermal c

Basic blocks of a generalized measurement system, Can you explain the basic...

Can you explain the basic blocks of a generalized measurement system? Draw them and illustrate their functions.

Calculate the density of the composite, Five kilograms of continuous boron ...

Five kilograms of continuous boron fibers are introduced in a unidirectional orientation into 8 kg of an aluminum matrix. Calculate a.  the density of the composite b.

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