Eng Machhine components test review

How are nuts, bolts, and screws different from welding and adhesives?

 

nuts, bolts, and screws are removable/serviceable.

 when you buy metric threads, you need to look for ___ and ___

 major diameter and pitch

 when you buy unified threads, you need to look for ___ and ___

Major diameter and TPI

What are the drawing styles for Threads

•  Pictorial- take a long time to draw

•  Schematic- most common type

•  simplified- easy to draw the outside diameter, minor diameter are the hidden lines, can be confusing.

 when should a Thrust bearing be used?

•  when a thing is rotated at different speeds or pressure against each other.

 what is required when  using a rolling element bearing?

 a hardened or heat treated shaft.

 what is the recommended PV value for sleeve bearings?

 50,000 or under

 what is the recommended PV value for Rolling element bearings?

 100,000 or over.

 what happens when you have a PV value that is between these two values?

•  it is up to the discretion of the engineer and further research should be conducted.

 the most common material used for Springs is…

 music wire

 a use of compression springs

•  pens, beds and other furniture

 use of extension Springs

 a trampoline, a screen door

use of torsion spring

•  clipboard, hair clip

 use of constant for spring

•  tape measure

 use of clock spring

motors

 what is special about points above the light service level curve?

 points above must be redesigned

A linkage is a ___ that connects to two or more____

 Mechanism,  levers

 a linkage can ___  the range of motion,___  the direction of motion, or convert ___motion to ____ motion.

Extend, change, linear, and rotational

___ turn something to face a new axis

rotation

____  move something along the x, y, or z-axis

translation

 how many classes of levers exist

3