CFS Blind Fasteners & Rivets 3

Question 1

A lockbolt (e.g., Huck C6L or Hi-Lok) is distinguished from a break-mandrel blind rivet primarily because:

Accepted Answer

A lockbolt uses a swaged collar on the pin rather than a collapsing rivet body

Answer

A lockbolt is installed from both sides simultaneously

Answer

A lockbolt is made exclusively from titanium

Answer

A lockbolt does not require a pre-drilled hole

Question 2

In aerospace applications, why are blind fasteners often preferred over solid rivets for repair work even when both sides of the structure are accessible?

Accepted Answer

Blind fasteners eliminate the need for a bucking bar, simplifying one-person repair in confined areas

Answer

Blind fasteners weigh less than solid rivets in all configurations

Answer

Blind fasteners are always stronger than solid rivets of the same diameter

Answer

Aerospace specifications prohibit solid rivets in repair situations

Question 3

Which of the following best describes the 'clamp force' (clamping load) developed by a blind rivet?

Accepted Answer

The compressive preload applied to the joint members as the blind side bulge forms and the mandrel breaks

Answer

The shear load capacity along the rivet shank

Answer

The tensile strength of the mandrel before fracture

Answer

The torque required to install a threaded blind insert

Question 4

A self-plugging blind rivet retains the mandrel in the set rivet body. What is the primary reason for this design feature?

Accepted Answer

To seal the rivet body and increase shear and tensile strength by adding mandrel load transfer

Answer

To allow the rivet to be removed with a standard screwdriver

Answer

To prevent the rivet from being set incorrectly

Answer

To reduce the installation tool pull force required

Question 5

What is the purpose of the countersunk (flush) head style available in blind rivets, such as those meeting NAS 1738?

Accepted Answer

To create an aerodynamically smooth surface flush with the parent material, reducing drag in aerospace assemblies

Answer

To increase the rivet's grip range by countersinking the installation side

Answer

To allow installation with a standard hammer instead of a pull tool

Answer

To increase the tensile strength of the rivet head

Question 6

When a blind rivet is specified as '1/4-inch diameter, medium (M) head,' the 'M' designation indicates:

Accepted Answer

The head style is a medium flange universal head with a larger bearing area than a standard head

Answer

The rivet body is made of mild (M) steel

Answer

The rivet meets metric (M) dimensional standards

Answer

The mandrel material is manganese alloy

Question 7

Which test method is most commonly used to verify the shear strength of a blind rivet per IFI-114 or similar standards?

Accepted Answer

Single-lap shear test using two overlapping metal coupons joined by the rivet and pulled in opposite directions

Answer

Rockwell hardness test on the rivet body

Answer

Peel test pulling the coupon perpendicular to the rivet axis

Answer

Salt spray (fog) test to measure corrosion resistance