WELD TESTING

DESTRUCTIVE AND NON-DESTRUCTIVE

DESTRUCTIVE TESTING

These can be divided into two parts, Tests capable of being performed in the workshop. Laboratory tests. microscopicmacroscopic , chemical and corrosive.

REASONS Defects occur during welding which affect the quality and hardness of the plate Other defects occur through lack of knowledge of and skill of the welder For the training of welders

WORKSHOP TESTSTENSILE IMPACT BENDING HARDNES

FATIGUE

CRACKING

TENSILEMaterial is sectioned and edges rounded of to prevent cracking. Punch marks are made to see elongation.

TENSILE

BEND TESTING Shows Physical condition of the weld Determine welds efficiency Tensile strength Ductility Fusion and penetration

BEND TEST Bend through 180 the specimen should be a minimum of 30mm wide The fulcrums diameter is 3x thickness of the plate The bottom rollers have a distance of the diameter of the former + 2.2 times the thickness of the plate Upper and lower surfaces ground or filed flat and edges rounded off. the tests should be one against the root -another against the face ,and in some cases a side bend.O

Root bend

FACE BEND

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IMPACT CHARPY AND IZOD Gives the toughness and shock loading of the material and weld at varying temperatures with a notch such as under cut The measurement is the energy required to to break a specimen with a given notch o 2mm depth at a 45 bevel or a “U” notch.

TEST MACHINE

CHARPY

IZOD

ANY QUESTIONS

HARDNESS TESTS. This gives the metals ability to show resistance to indentation which show it’s resistance to wear and abrasion. The tests areBrinell Rockwell Vickers diamond pyramid Scleroscope

VICKERS HARDNES