Scotsman MAR 106, Руководство по обслуживанию

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4. REFRIGERANT CHARGE
WATER COOLED MODELS
The below refrigerant charge is approximate.
When charging, set at 15 or 17 bar head pressure
according to the model and charge so that frost
line extends out of the evaporator two third way
to compressor after fifteen minutes of operation.
AIR COOLED MODELS
When charging set at 16 bar (225 psi) the head
pressure.
5. MECHANICALS
A. Motor Shaft Pulley
MAR units are generally equipped with two
pulley and by changing the belt from one to
the other, the speed of drum can be changed.
MAR Machines are factory delivered with
pulley to rotate the evaporator drum at the
lowest possible R.P.M. to obtain "THICK" (2
mm gauge) scale ice.
Replacing standard by alternative/supplied
pulley on motor shaft evaporator drum R.P.M.
increases to the point to produce "THIN"
(1 mm gauge) scale ice.
R.P.M. R.P.M.
for "thick" ice for "thin" ice
MAR 56 AS/WS 0.9 1.25
MAR 76 AS/WS 1.1 1.25
MAR 106 AS/WS 1.5 2.3
MAR 126 AS/WS 2.4 ****
MAR 206 AS/WS 1.05 1.6
MAR 306 AS 1.6 2.9
MAR 306 WS 1.8 2.9
V belts used on motor shaft pulley and gear
box are type:
MAR MAR MAR MAR MAR MAR
56 76 106 126 206 306
XPZ750 XPZ 900 XPZ 937
B. V Belt
V belt used on motor shaft pulley and gear
box. When changing the V belt be careful to
adjust it for proper tension and alignement.
It should be snug not tight. A way to roughly
check belt tension is to apply a firm hand
pressure in the middle of the longest belt
span. If the belt is correctly tensioned, you
should be able to depress it about 10 m/m out
of line.
C. Gear Reducer
Then gear reducer is mounted on the right
side frame of evaporator drum basin to which
it is firmaly secured with four nuts.
The gear reducer bore in which passes the
drum shaft to be driven, has a keyway.
Two fiber keys are used to engage the gear
reducer to the drum shaft, they are in series in
the gear reducer bore, and shaft keyways.
Should the driving strain be excessive, the
two fiber keys will shear.
MAR 56-76-106-126 are equipped with a gear
reducer having a ratio of 1/600.
MAR 206 and 306 have a gear reducer with a
ratio of 1/552.
The gear reducers are greased for life,
therefore they do not require any mainte-
nance.
REFRIGERANT CHARGE AND OPERATING PRESSURES
MAR 56-76 MAR 106 MAR 126 MAR 206 MAR 306
A W A W A W A W A W
Refrig. charge (gr) 1500 1000 2000 1150 2200 1250 4100 2300 5900 2500
Head press. (bar) 15-17 17 15-17 15 15-17 15 15-17 16 15-17 14
Head press. (psi) 212-245 245 212-245 212 212-245 212 212-245 230 212-245 200
Suction press. (bar) 2.2 1.8 1.6 1.6 1.6 1.6 1.9 1.9 1.0 1.75
Suction press. (psi) 32 26 23 23 23 23 27 27 14 11
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