Fasteners Flashcards
What is a bolt?
Is a metal rod with external threads on one end and the head on the other.
When a high-quality bolt is threaded into a part without a nut it can also be called?
Cap screw
How do you measure a bolt?
Bolt size, bolt head size, bolt length, and thread pitch
How do u measure a bolts size?
It is a measurement of the outside diameter of the bolt threads
How do you measure a bolt head?
It is the distance across the flats or outer sides of the bolt head. It is the same size as the wrench size.
How do you measure a bolts length?
Is measured from the bottom of the bolt head to the threaded end of the bolt.
How do you measure the thread pitch on a bolt?
Is the same as thread coarseness. With imperial fasteners, it is the number of threads per inch. With metric fasteners, it is the distance between each thread in millimeters.
What are the four thread types?
Coarse threads (UNC unified national coarse) Fine threads (UNF unified national fine) Metric threads (SI system international) Extra fine (UNXF unified national extra fine)
What is the bolt grade or tensile strength?
Refers to the amount of pole or stretch a fastener can withstand before breaking.
What are the two methods used to determine the strength of a bolt?
Slash marks: the more lines the stronger the bolt. Number system (metric bolts): the higher the number the stronger the bolt.
How do you determine the grade of a bolt using the slashmarks or lines on the head?
Always had 2…
For example if the bolt head had three lines on it, simply add 2 to 3. Which means the grade for that bolt is grade 5.
How do you find the grade of a metric bolt?
Metric bolts use a number system, the number shown on the top of the bolt is not only the strength but also the grade it is.
Example: bolt head reads 8, that means the grade of the bolt is grade 8.
What does SAE stand for?
Imperial
What are imperial fasteners measured in?
Measured in inches
What are metric fasteners measured in?
Measured in millimetres
What can you use that is found in a shop to measure the threads of a bolt?
You can use a tap from the tap and die set. Just find the tap that fits, and the number on top of the tap is the measurement of the threads of the bolt.
You can also use a ruler
What is the terminology for a nut?
Has internal threads and usually is a hex (6sided) outer shape. When a nut is screwed onto a bolt, a powerful clamping force is produced.
What tools can be used to restore external threads?
Thread file, rethreading tool, rethreading die
What tools can be used to restore internal threads?
Internal thread chaser, hand tap
What is a helicoil?
A HeliCoil is a coiled-wire type of thread repair insert used to create internal screw threads to accommodate standard-sized fasteners.
What devices are used for locking nuts and bolts?
Cotter pin, lock wire, flat metal locks, lock ears
What methods can be used to remove a seized nut?
Penetrating oil, nut splitter, hacksaw, chisel, has torch for heat
What is the difference between a flat washer and a lock washer?
Flat washers increase the clamping surface under the fastener, and prevent the fastener from digging into the part.
Lock washer prevent the bolt or but from becoming loose under stress and vibration.
What are torque specifications?
Are tightening values for bolts and nuts that is given by the auto manufacturer.