Drill Bits and Sizes

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What is the primary function of drill bits?

To power a drill

To create holes of non-circular cross-section

To attach to a drill

To remove material and create holes of circular cross-section (correct)

How do drill bits typically cut through a work piece?

By linear motion only

By rotation and linear motion

By rotation only (correct)

By vibration and oscillation

In which country are fractional inch and gauge drill bit sizes commonly used?

Australia

Canada

United Kingdom

United States (correct)

What is the most common increment of drill bit sizes available in a market stall?

1 mm Signup and view all the answers

What was published in the United Kingdom in 1959?

British standards for replacing gauge size drill bits with metric sizes Signup and view all the answers

Where can you find drill bits in 0.1-mm increments?

Engineers' store Signup and view all the answers

What is the primary purpose of centre drills?

Drilling lathe centres Signup and view all the answers

What is the standard included angle for centre drills?

60° Signup and view all the answers

What is the tolerance range for standard-tolerance bolts?

+0.000 to -0.0055 in. Signup and view all the answers

Why is cad plating not possible for close-tolerance bolts?

Close-tolerance bolts are manufactured to tight specs Signup and view all the answers

What is the definition of a light drive fit for an AN hex bolt?

An interference fit with a clearance of 0.0006 in. Signup and view all the answers

What can be done to eliminate friction during fitting of close-tolerance bolts?

Place the bolt in a freezer prior to fitment Signup and view all the answers

What is the primary factor that determines the required temperature for a shrink fit?

Total expansion required Signup and view all the answers

What is the increase in unit length of any section of metal in any direction for an increase in temperature of 1 °C?

Coefficient of linear expansion Signup and view all the answers

Which of the following materials has the highest coefficient of linear expansion?

Nickel steel Signup and view all the answers

What is the purpose of considering the allowance for shrinkage when calculating the total required expansion?

To ensure the correct fit of the piece Signup and view all the answers

Which of the following heating methods is not listed as an option?

Laser heating Signup and view all the answers

What is the purpose of using a refrigerator for cooling a piece?

To slowly cool the piece Signup and view all the answers

What is the primary difference between interference fit and transition fit?

The size difference between the mating parts Signup and view all the answers

What is the purpose of selective assembly in determining the type of fit?

To determine whether the fit is clearance or interference Signup and view all the answers

What type of fit is characterized by a small size difference between the mating parts?

Transition fit Signup and view all the answers

What type of fit requires the use of a hydraulic press for assembly?

Force fit Signup and view all the answers

What is the primary characteristic of a running fit?

The shaft is designed to rotate in the hub Signup and view all the answers

What is the purpose of finely finished and accurate surfaces in achieving a transition fit?

To produce very small differences in size Signup and view all the answers

What is the primary method for inspecting a shaft or other part for bow?

Using a dial test indicator Signup and view all the answers

What is the term used to describe the rotation of a shaft or component about its longitudinal axis?

Twist Signup and view all the answers

What is the primary source of information for the inspection technique or method for twist?

Manufacturer's manual Signup and view all the answers

What is the common method used to inspect compressor blades for bow?

Using feeler gauges and a straight edge Signup and view all the answers

What is the purpose of reference lines or datum points on a shaft?

To compare to maintenance manual dimensions or limits Signup and view all the answers

Which of the following is NOT a method of checking for wear?

Dynamometer Signup and view all the answers