26 FD151 Gas Compressor
DISTANCE PIECE OPENING, 1/4 INCH NPT
V-RINGS POINT
MODEL
CONDITIONS
SERVICE
UPPER
LOWER
UPPER
LOWER
1) General gas transfer
Plugged to allow the
Pipe to drain or vent
SPRING SPRING
FD151
Inlet pressure:
distance piece pressure
with a shut-off valve.
Above 15 psia
to reach its own level.
Distance piece must be
drained weekly to
2) Highly toxic gases
Pressurized via an
prevent an accumulation
external gas source to a
of oil or condensate.
pressure below suction
pressure and above
atmospheric pressure.
Or, vented to atmospheric
pressure (at a suitable
location) or to a low-
pressure flare.
PURGING AND DRAINING OF DISTANCE PIECE
AND PISTON ROD PACKING ORIENTATION
Model
Clearance: Conrod
Clearance: Wrist
Cylinder Bore
Cylinder
Piston Ring
FD151
Bearing to Crankshaft
Pin to Wrist Pin
Diameter (Max)
Finish (RMS)
Radial Thickness
Journal
Bushing* (Max)
(Min)
Stage 1
0.0005 0.0025
0.0009
2.504
16
•
32
0.082
Stage 2
0.0005 0.0025
0.0009
1.254
16
•
32
0.086
Model
Clearance: Oil
Crankshaft End
Flywheel Runout
Clearance: Crosshead
Crosshead Guide
Pump Adapter Shaft
Play (Cold)
at O.D. (Max)
to Crosshead Guide
Bore Finish (Max)
to Bushing* (Max)
Bore (Max)
FD151
0.0050
0.002 0.003
0.020
0.011
32 RMS (Limited
number of small
pits and scratches
are acceptable)
CLEARANCES AND DIMENSIONS
PISTON CLEARANCE ‘X’ (COLD)
(See Figures 5.4A and 5.4B)
Caution: Always relieve pressure in
the units before attempting
any repairs.
Model
“X” Inches (Millimeter)
Minimum
Maximum
FD151
0.025 (0.64)
0.049 (1.24)
*Dimensions for honing are included with new bushings (which must be installed, then honed).
Dimensions in inches.
APPENDIX C
