CWB Study guides, Class notes & Summaries

To measure the strength of a welded joint what mechanical test would you prescribe? a) A transverse weld tension test. b) A charpy test. c) A CTOD test. d) An all weld metal tension test. e) A side bend test. - correct answer a) A transverse weld tension test. Select the cutting process that would provide the narrowest heat affected zone when cutting 12.5 mm (0.5 in) thick carbon steel. a) Oxy-acetylene cutting. b) Air-carbon arc cutting. c) Oxy-propane cutting. d) Plasma ...

Active Flux significantly influence the weld puddle - add manganese, silicon, chromium to weld metal - typically bonded type flux Arc Blow The deflection of an arc from its normal path due to magnetic forces. Autogeneous Weld A fusion Weld made without filler metal Duty Cycle The time during a ten-minute test period, expressed in percentage, that a power source can operate at the rated output without overheating Fused Flux A granular flux produced by mixing the ingredients, followed by melti...

On a radiograph, undercut appears as a _________ line. (A) light (B) dark (B) dark What is the Canadian Standard for safety in welding? CSA W117.2 What is the typical three-phase input voltage in most Canadian welding shops? 600V True or False: The cable from the workpiece back to the welding machine is called the "ground lead". False. The correct term is the "work lead". What is the type of radiation that can damage living cells? Ionizing Name two examples of ionizing radiation. X-ray...

What is the term used to describe the following condition of lost corrosion resistance? "When certain stainless steels are heated between 500-850° C, carbides form at the grain boundaries and cause a local depletion of chromium." (A) Oxidization (B) Increased toughness (C) Solution heat treatment (D) Sensitization (D) Sensitization Note: Also known as "carbide precipitation" -- Chromium binds to carbides, and "sweats out" at the grain boundaries On a radiograph, undercut appears as a ...

What is the description of damage of a brittle fracture? Sudden rapid fracture under stress (residual or applied) where material exhibits little or no evidence of ductility or plastic deformation What type of Steel are of primary concern with brittle fractures? Carbon and low alloy steels. 400 series SS are also susceptible What has a significant influence on toughness and resistance to brittle fractures? Steel cleanliness and grain size In most cases brittle fractures occur only at what temp...

During arc welding there is a zone adjacent to the weld metal that reaches high temperatures but does not melt. What is the name of this region? Heat Affect Zone (HAZ) In parallel electrical circuits, the voltage across each resistor is the same since each path is connected to the same voltage source. Select the correct statement. A. in each parallel path the resistance must be equalized to create equal voltage. B. the current flowing in each parallel path must be the same as the voltage. C. th...

Increased oxygen content of a weld is likely to: A) increase the upper shelf Charpy energy B) lower the upper shelf of the Charpy energy C) have no effect on the carbon equivalent D) produce HICC at temperatures above 150°CB On a thin plate the cooling rate is more sensitive to heat input and doubling the heat input will A) reduce the cooling rate four times B) reduce the cooling rate by half C) double the cooling rate D) not affect the cooling rateA High energy input welds typically result i...

Complete the following: A) Chromium stabilizes the _______ form of iron. B) Nickel stabilizes the _______ form of iron A) BCC B) FCC If a straight chromium steel of 18% Cr and < 0.1% C is heated to 1,000°C will it transform to austenite or remain as ferrite? Remain as ferrite What is the predominant structure of an 18% CR, 8% Ni steel at room temperature? Austenite The chromium content of a stainless steel is 20%. Is it likely this is a martensite grade? No What does the letter L signif...

Define Compression ? To reduce in volume, or the state of being compressed. To force together or into less space Define Contraction? To become reduced in size. To pull together, shrink or wrinkle. Define Distortion? The act of distorting. A physical change in shape by bending, twisting or warping. Define Ductility? Capability of being easily molded or shaped Define Expansion? Enlargement or increase. Increase in the dimension of a body Define Intermittent Welding ? Welding that is not conti...

Alloys are mixtures of a metal with: both metals and non-metals Which of the following is not involved in the steel making process? nitrogen furnace Which of the following is not a class of steel produced from pig iron? semi-rimmed steel When a plate is made, most of the rolling will usually take place in one direction, resulting in the formation of elongated inclusions. Elongated inclusions such as these are called: stringers Which of the following atomic structures are the most closely pac...

To measure the strength of a welded joint what mechanical test would you prescribe? a) A transverse weld tension test. b) A charpy test. c) A CTOD test. d) An all weld metal tension test. e) A side bend test. a) A transverse weld tension test. Select the cutting process that would provide the narrowest heat affected zone when cutting 12.5 mm (0.5 in) thick carbon steel. a) Oxy-acetylene cutting. b) Air-carbon arc cutting. c) Oxy-propane cutting. d) Plasma arc cutting. e) Laser beam cutting e)...