Reciprocating Compressor Cylinder Components A+B Assignment

Question 1

True or False;
A single acting compresses on one side of the piston only

Answer 1

True

Question 2

A piston rod is not running true through the packing. What is this called?

Answer 2

Rod Run Out

Question 3

True or False;
Uncut rider rings should be used when they pass over a valve port.

Answer 3

True

Question 4

What is the purpose of measuring or trammeling the position of the piston rod relative to the crosshead?

Answer 4

To facilitate quick assembly

Question 5

What is a ‘rule of thumb’ for setting piston to cylinder head clearance if you do not have manufacturer specifications available?

Answer 5

1/3 crank end 2/3 head end

Question 6

True or False;
Rod reversal is necessary to allow oil to flood around the crosshead pin.

Answer 6

True

Question 7

What type of cooling is most common on large compressors?

Answer 7

Liquid Cooling

Question 8

True or False;
It is important to keep the cooling water temperature above the incoming gas temperature to prevent condensation in the cylinders

Answer 8

True;

+5.5C (10F) above inlet gas temperatures

Question 9

What are three types of cylinders used in reciprocating compressors?

Answer 9

Cast Integral
Wet Liner
Dry Liner

Question 10

Which ring material is commonly used in oil free compressors?

Answer 10

Teflon

Question 11

Which end of the cylinder are clearance pockets installed on?

Answer 11

Head End

Question 12

What pressure is used for cylinder hydrostatic testing?

Answer 12

1.5 times the maximum working pressure

Question 13

Improper preload of the cylinder will not effect rod run out.

Answer 13

False;
Preload is to ensure that rod runout is within manufacturers spec, when the compressor frame and cylinders are at operating temp since thermal growth affects alignment

Question 14

2 reasons for keeping rod runout to to a minimum:

Answer 14

Minimize Wear
Minimize Leakage

Question 15

Three causes of rod runout:

Answer 15

1. Balance nut not square to crosshead
2. Worn crosshead or guides
3. Worn rider bands

Question 16

Pressure breaker rings are radially cut.

Answer 16

True

Question 17

Dots and / or letters on the packing rings should face the crankshaft.

Answer 17

False;
Face towards cylinder(pressure side)

Question 18

What is used on pairs of single-acting packing rings to ensure that the gaps don’t align?

Answer 18

Dowels

Question 19

Liquid-cooled packing cases are normally used in non-lubricated packing applications.

Answer 19

True;
Used to prevent shortened ring life caused by excessive heat in the packing case.

Question 20

Why does the cooling water enter the bottom of the flange and leave out of the top in liquid-cooled packing cases?

Answer 20

To prevent trapped air

Question 21

To prevent air from entering the cylinder, double-acting packing ring sets are used.

Answer 21

True

Question 22

2 reasons that cooling water enters the bottom of the cylinder near the discharge valves and then exits out the top near the suction valves?

Answer 22

1. Prevent cooling system from hydro locking
   2.Creates more even temperature across Cylinder