Ch3 Plumbing Flashcards
Pipes Rated by Tickness
Type K - underground
Type L - Medium (supply lines)
Type M - Thinner (carry condensation)
Type DWV - Used for drains and vents low pressure
*Bring Water to the Ground Slowly
Soil slowly filters
Fast = erosion
Roof and parking drainage - gutter or roof drain
green roof - slows
blue roof - create pond on roof returns water slowly
Plastic Pipe
More common than copper
Less friction
Smaller buildings - not enough fittings yet
*Supply and Waste Water Never Meet
Use air gap to separate
Health and Safety
Back Flow Preventer
If water backs up - mechanism switches to block water and pull in air instead.
Danger is negative pressure could be caused by fire hose and suck back dirty water. - Use vacuum breaker to prevent
Valves
Gate Valve
Glove Valve
Check Valve
Gate Valve
Maintenance shut offs - lots of turning
Min friction b/c controls a lot down stream.
Globe Valve
Faucets
Little turning
More friction - 1 thing down stream.
Check Valve
Backflow Preventer
Water moves one direction
Prevent building to building contamination.
P
(pressure in psi) = 0.433 x H (height)
0.433 - constant converts psi to height, inches to feet
Fixture - 4-20 psi min
50-75 psi in water main
Water seeks its own level
Vault Ball Valve
Replace Gate Valve
Black Water
Human waste or food waste
Lavatory
Sink
How high can fixture be if needs min 12 psi if 25 psi entering building
25-12=13
P=.433xH
13=.433xH
H=30’ (kinda typical)
If higher than 30’ pump water to tank on roof
Can pump to every tenth floor to prevent super high presure
Expansion Loop
B/c hot water pipes expand and contract
Inch worm looking bump
h = .5 length
Welded joint handle expansion
*We size pipes by pressure and flow.
Assuming not all fixtures will be on at same time
Use “Fixture Units” instead of total sum of gal/min and psi of all fixtures.