Welding Processes

Question 1

Name principle groups of processes included in fusion welding

Answer 1

arc welding

resistance welding

oxy-fuel welding welding

other fusion-welding processes

Question 2

What is the fundamental feature that distinguishes fusion welding from solid-state welding

Answer 2

fUSION WELDING IS JUST THE USE OF HEAT FOR WELDING

SOLID STATE WELDING USES PRESSURE OR PRESSURE WITH HEAT

Question 3

define what electrical arc welding is

Answer 3

Fusion-welding process in which coalescence of the metals is achieved by the heat of an electrical arc between an electrode and the work

Question 4

what do the terms arcon time / arc time mean

Answer 4

the proportion of hours worked that arc welding has accomplished

Question 5

Electrodes in arc welding are defined into two types. Define those two types

Answer 5

consumable - provide the source of filler metal in arc welding and is depleted over time

non-consumable - made of tungsten and is gradually depleted.

Question 6

What are two basic methods of arc shiedling

Answer 6

Covering the electrode tio

molten weld pool with a blanket of gas or flux

combination of the above stated

Question 7

Why is heat transfer factor in arc welding processes that utilize consumable electrodes?

Answer 7

Molten metal from the electrode is transferred across the arc and contributes to the heating of the molten metal

Question 8

Describe the shielded metal arc-welding process

Answer 8

Uses a consumable electrode consisting of a filler metal rod coated with chemicals that provide flux and shielding.

Question 9

why is shielded metal arc welding process difficult to automate

Answer 9

Electrodes must be changed frequently.

Question 10

describe submerged arc welding

Answer 10

Uses a continuous, consumable bare wire electrode and arc shielding is provided by a cover of granular flux..

Question 11

Why are temperatures much higher in plasma arc welding than in other processes?

Answer 11

Arc is restricted in diameter, thus concentrating the energy into smaller area

Question 12

Define resistance welding

Answer 12

.Utilizes a combination of heat and pressure to accomplish coalescence of the two faying surfaces

Question 13

Describe the sequence of steps in the cycle of a resistance spot welding

Answer 13

1) Insert parts between electrodes
2) Squeeze parts between the electrodes
3) weld
4) Hold
5) Open and remove

Question 14

What is resistance projection welding

Answer 14

Coalescence occurs at one or more relatively small contact points on the parts

Question 15

Why is the oxyacetylene weldingprocess favored over the other oxyfuel welding processes

Answer 15

Acetylene and oxygen burn hotter than other oxy-fuels.

Question 16

Electron beam welding has a significant disadvantage in high-production applications. What are those disadvantages?

Answer 16

.Must be performed in a vacuum

Question 17

Laser-beam welding and electron-beam welding are often compared because both produce very high power densities. LBW have certain advantages over EBW. What are they?

Answer 17

No vacuum chamber

No x-rays

Lasers can be focused/directed easily

Question 18

What is friction stir welding and how is it different from friction welding?

Answer 18

Solid state welding process in which a rotating tool is fed along the joint line, generating friction heat and mechanically stirring the metal to form a weld seam

Question 19

What is a sonotrode in ultrasonic welding?

Answer 19

Actuator that is attached to one of the parts to be welded and provided he oscillatory motion