OP-755 Part 2 Pages 197-401 - Personal Page of GENE SLOVER

235
head ports and the design of the
piston assembly operate to provide
dashpot buffing at both extremes
of piston stroke. The upper
head buffing space is equipped
with needle type vent valve.
10. The piston and rod assembly
is a single cupped-leather
type whi ch operates to seal by
pressure distension. It consists
of a steel rod (2.5 in. dia.) and
a bronze piston, Hith the leather
secured by bolted attdclnuent thru
a piston folloHer. This follower
is shaped to prevent collapse of
the leather and to function as the
dOHn stroke buffer plunger.
The upper end of the rod is secured
to the crosshead Hith a steel pin
(1. 5 in. dia.) 'lockedin place Hi th
1/2 inch set screw.
11. The cylinder head pressure
ports are flange coupled to
special steel leads (2.375 ins.
dia.) which extend upward Hi th
!ieasyllbends to attachment Hith
the A-end valve plate on the electric
deck.
Power Drive Assembly
12. The power drives for
all hoists are located on the electric
deck with arrangement as
shown on drawing number 215940.
Each power plant consists of an
electric motor with controller
panel and remote push-button station,
a reduction gear, a variable
displacement pump and a solenoid
brake.
13. El ec t r i c motor. - The
electric motor is an induction type
of ccmmercLaL manufacture (RelianceElec.
&Eng. Co.) mounted vi.t.h
rotor axis horizontal and having
the following specification data.
" ',- UPPER PAWL CARRIER
'~ UPPER B INTERMEDIATE
CONNECTING BAR
"------ CAM ON CONNECTING BAR
'~UPPER INTERMEDIATE
PAWL CARRIER
CROSSHEAD
PISTON ROD
'~LOWER INTERMEDIATE
PAWL CARRIER
'- LOWER CONNECTING BAR
.r=:; LOWER PAWL CARRIER
Fig. 43 - Rack Arrangement