Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
15 Cards in this Set
- Front
- Back
|
Four functions of a seal |
Retain lubricants or liquids Exclude contaminates Seperate fluids Confine pressure |
|
|
State the following terms Positive seal Non positive seal |
Prevent even I minute amount of fluid to pass Allows a small amount of internal leakage to provide |
|
|
List an example for of seal for postive and non positive |
O-ring Gland packing |
|
|
Definition of a static seal |
A seal that is compressed between ridigly conncent parts is a static seal |
|
|
Difference between a jointing and a gasket |
Gasket when the jointing material is cut to shape it is called a gasket Jointing material used between a bolted surface to form a seal |
|
|
Example of the flowing type of jointing materials Rubber Copper Cork Fibre |
Flanges of water pipes and pumps Steam pipe flanges and high pressure Gear boxes, fuel pumps, engine gaskets Washes for oil, water and fuel tanks |
|
|
Definition the term gasket |
A device for affecting a seal between two surfaces |
|
|
Two types of bolted joint assembly |
Floating assembly pipe flange with gasket Ridid assembly o ring |
|
|
Forces acting on a floating assembly joint |
Initial force Hydrostatic force Residual force Residual stress |
|
|
What does hydrostatic force mean |
Force trying to separate the flanges due to pressure |
|
|
What does stress relaxation mean |
Occur in the gasket after a long time and on heat and is the loss if elasticity |
|
|
When making gaskets why should you not use bell pein hammers |
Possiblity of damaging the surface to be sealed and compressing the gasket |
|
|
How to mark a gasket |
Mark the shape of a gasket by tracing around the edges with a pencil or marker or alternately cost the surface with a light snare of oil or bearing blue |
|
|
What pressure is a spiral wound gasket designed to be used at |
300psi and above |
|
|
Method of fastening that prevents the swg from unwinding |
Spot wielding |
