moyno Version 3, Руководство по обслуживанию

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Moyno 2000 pumps have been designed for minimum
stuffing box leakage when properly maintained. If leakage
cannot be tolerated, then a mechanical seal should be used.
3-5. G3 DRIVE ASSEMBLY ADJUSTMENT
Ensure that the chain on the drive assembly has no bows.
The chain tension can be adjusted by loosening or tightening
the idler adjusting screw (E, F,fig. 4-10).
The chain tension should be checked again and read-
justed after the first 20 hours of operation.
The assembled torque limiter (3) and sprocket (4) on the
bridge breaker assemblies are set at the factory to a reading
of 540 lbs on a spring scale. (See fig. 3-1.)
If during opera-
tion the torque limiter slips, the torque should be checked
and if necessary, reset. To check the torque limiter setting,
use a spring scale as shown in the diagram with a properly
sized chain to fit the sprocket (4). Attach the scale to the
chain and pull, noting the value on the scale dial when the
torque limiter slips. To adjust the torque, loosen the three
capscrews on the torque limiter collar. Turn the collar clock-
wise to increase torque, or counter-clockwise to decrease it.
Tighten capscrews until heads bottom and again check the
torque setting. Repeat this process until the slipping point is
within 5 lbs of the 540 lb value. When the correct torque is
achieved, tighten setscrew to lock collar in position.
Figure 3-1. Torque Setting Diagram
4-1. MAINTENANCE
Note: In this section, the first reference to each pump part
will be followed by a number or a letter in parentheses
( ). These numbers and letters are those used to iden-
tify the pump parts and hardware items in the foldout
Exploded Views (fig. 4-7 or 4-10 as indicated).
4-2. GENERAL
The Moyno 2000 pump has been designed for a minimum
of maintenance, the extent of which is routine adjustment
and lubrication of packing. The pump is one of the easiest to
work on, in that the main elements are very accessible and
require few tools to disassemble.
4-3. PACKING ADJUSTMENT
Pumps. Packing gland nuts should be evenly adjusted so
they are little more than finger tight. (See fig. 4-1.) Over-
tightening of the packing gland may result in premature
packing failure and possible damage to the shaft and gland.
When packing is new, frequent minor adjustments during
the first few hours of operation are recommended in order to
compress and seat the packing.
1. Upon initial start-up of the pump, adjust the gland nuts
for a leakage rate of 1-2 drops per second until the packing
has seated and adjusted to the operating temperature (ap-
proximately 10-15 minutes).
2. If leakage is excessive after 15 minutes of operation,
tighten the gland nuts until a desired leakage rate is ob-
tained.
CAUTION: Do not tighten until zero leakage is obtained.
Over-tightening of the packing gland may
result in accelerated wear on the packing
and damage to the shaft. In those situations
where no packing leakage can be tolerated,
consult your Moyno Authorized Service
Representative.
Figure 4-1. Cross Section of Stuffing Box
Bridge Breaker.
Packing for the bridge breaker is ad-
justed by means of cylindrical packing glands (25, fig. 4-10)
which are threaded into the bearing retainers (28). Holes in
the packing gland allow the use of a punch to rotate the
gland. The packing is compressed by rotating the gland in a
clockwise direction when viewed from the shaft end.
4-4. PACKING REPLACEMENT
When leakage can no longer be regulated by tightening
the gland nuts, remove and replace the packing. The entire
pump need not be disassembled to replace the packing.
Briefly, replace as follows:
1. Remove packing gland nuts (E, fig. 4-7), and slide
gland (12) and slinger ring (11) back along drive shaft (4).
2. Use a pair of packing extractors (fig. 4-2) to remove
three packing rings (10), lantern ring halves (13) and three
additional packing rings (10).
3. Inspect surface of drive shaft for excessive wear or
grooves due to packing rub. If shaft is worn, or is badly
scored or grooved, it should be replaced.