1. feed the casting at a rate consistent with the rate of solidification
2. act as a reservoir for molten metal
3. feed molten metal from the pouring basin to the gate
4. help feed the casting until all solidification takes place
feed molten metal from the pouring basin to the gate
1. at re-crystallization temperature
2. between 100 C to 150 C
3. between re-crystallization temperature
4. above re-crystallization temperatur
above re-crystallization temperatur
1. GMAW
2. GTAW
3. Submerged Arc Welding
4. none of these
GTAW
1. Finishing a drilled hole
2. Producing a large hole without drilling
3. Truing a hole for alignment
4. Enlarging a drilled hole
Producing a large hole without drilling
1. hardness of abrasive grains
2. ability of the bond to retain abrasives
3. hardness of the bond
4. ability of the grinding wheel to penetrate the work piece
ability of the bond to retain abrasives
1. m+n
2. m x n
3. m-n
4. m/n
m-n
1. 1/x
2. x4/5
3. x2
4. x1/2
x1/2
1. A reduction of pressure to vapour pressure
2. A negative pressure gradient
3. A positive pressure gradient
4. The boundary layer thickness reducing to zero
A positive pressure gradient
1. Always isentropic
2. Always choked
3. Never choked
4. Never isentropic
Always choked
1. The convective resistance of the fluid is negligible
2. The conductive resistance of the fluid is negligible
3. The conductive resistance of the solid is negligible
4. None of these
The conductive resistance of the fluid is negligible