1. STOP PLATE
2. VALVE SEAT
3. SPRING
4. PLATE

What is "valve lift"?

Wears Valve out prematurely

(increases impact, valve flutter,)

1. Lighter
2. Limited damage
3. reduce noise

• Better flow, less turbulance

• Which valve has the least restriction to flow?

• The RING VALVE (no flow reducing webs

Name 2 types of positive displacement compressors

piston

vane

Pressure switch

Inlet valve unloading

• Against a shoulder
• on a taper with a locknut

• Store compressed air
• Dampen pulsation

• barometer
• manometer
• bourdon tube

• Labyrinth Compressor

Small end is Reciprocating

Big end is rotary

• With a Wrist pin

• Connects frame to cylinder
• prevents oil from travelling along the piston rod into the compression cylinder
• allows access for maintenance and runout readings

• Can shim shoes at the bolt locations in order to alter the clearance between cross head and guide.
• removable shoes are easier to replace.

• Floating pin
• fixed pin

• 0.0015”

7-10 mils

long feeler gauges and check in at least 3 spots.

• Straight cut
• bias cut

What is the purpose of a Desiccant-type dryer?

• Prevent piston from touching cylinder during start up?
• Support the weight of the piston and half the wight of the piston rod.

• Double nutting
• Hole Drilled Through the nut and rod with a pin

• Set the crank head clearance at 1/3 and the head end clearance at 2/3 of total.

• NO, depends on angle of the crank throw

• Confines the compressed gasses as the piston pushes on them

• houses the inlet and outlet gas valves
• provides a bore that the cylinder can slide back and forth
• cooling passages
• mounting for clearance pockets to provide volume delivery control
• mounting location for the piston rod packing

• NO, travels by convection to a cooling tank

• When discharge gas temps are over 121c* (250f*)

• (cooling water enters near discharge, exit at suction)
• Cooling water enters bottom exits at top

• Wet liner

• Teflon

• Clearance pockets

• Clearance pockets
• (increases the size of the clearance volume(space that prevents piston from hitting the head)
• if clearance volume is increased, it reduces the amount of compressed has leaving the cylinder.

• adding more clearance volume

• The "Variable Volume Clearance Pocket" (VVCP)

• Dial bore gauge

•  1 1/2 x the Max allowable working pressure.

• Washed in hot soapy water and dry immediately with a lint free rag.

• attach a pres gauge when shut down. run compressor. should have steady pressure between suction/discharge.

wild fluctuations indicate piston rings are leaking badly.

• annually

1. Pressure breaker
2. radial cut
3. tangent cut
4. back-up

1. metallic
2. non-metallic

• Limits the flow of gas into the packing on the suction stroke.

• Limits the flow of gas into the packing on the suction stroke.

( Radial cut, First ring in packing)

• TANGENT CUT

• prevent the extrusion of the softer non metallic rings under high pressure and temperature conditions.

• Gasketed joint

• in an oil-free service.
• (Flow enters through the bottom of the packing case and exits at the top to prevent any areas where air could be trapped)