KIRLOSKAR 65-DSM 315M, Instruction On Installation, Operation And Maintenance

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4 Line supplying the
2 Vacuum equalizing line
1 Tank under Vacuum
4
5
6 Connecting line
seeling liquid
5 Valve
7 Valve
3 Valve
7
6
3
2
1
A check for parallel alignment is made by placing a straight-edge across both coupling periphery at the top,
bottom and both the sides. The unit will be in parallel alignment when the straight-edge rests evenly on the
coupling periphery at all positions. Care must be taken to have the straight-edge parallel to the axis of the
shafts.
A check for angular alignment is made by using an outside caliper across the width of the coupling faces at
various points.
Coupling alignment can be checked with dial gauge indicator as shown in Fig. 2.
GROUTING
When the alignment is correct, the foundation bolts should be tightened evenly but not too firmly. The unit
can then be grouted by working soft concrete under the edges. Foundation bolts should not be fully tightened
until the grout is hardened, usually 48 hours after poring.
FACTORS THAT MAY DISTURB ALIGNMENT
The unit should be periodically checked for alignment. If the unit does not stay in line after being properly
installed, the following are possible causes:
(a) Setting, seasoning of the foundation
(b) Pipe strains distorting of shifting the machines
(c) Wear of the bearings
PIPING
Both suction and delivery pipes and accessories should be independently supported near the pump so that
when the flanges bolts are tightened no strain will be transmitted to the pump casing. It is usually advisable
to increase the size of both suction and delivery pipes at the pump nozzles in order to decrease the loss of
head from friction and for the same reason piping should be arranged with as minimum bends as possible, as
these should be made with along radius wherever possible. The pipe lines should be free from scales, welding
residuals etc., and have to be mounted in such a way that they can be connected to suction and delivery
flanges without any stress on the pump. Adequate supports should be given to pipe lines to that weight of
the pipe lines does not fall on the pump. The use of minimum number of the bends and other fittings will
minimise the frictional losses.
SUCTION PIPE
The suction pipe should be as short as possible. This can be achieved by placing the pump near the liquid to
be pumped. The suction pipe must be kept free from air leaks. This is particularly important when the suction
lift is high. A horizontal suction line must have a gradual rise to the pump. Any high point in the pipe will be
filled with air and thus prevent proper operation of the pump. A concentric taper piece should not be used in a
horizontal suction line as it forms an air pocket in the top of the reducer and the pipe. Use an eccentric piece
instead.
The end of the suction pipe must be well submerged to avoid whirlpools and ingress of air but must be kept
clear of nay deposits of mud, silt, grit etc. The pipe must be clear from any side of wall by at least 450 mm.
The end of the suction pipe should be provided with a strainer of sufficient open area.
DELIVERY PIPE
A check (non-return) valve and a gate of sluice valve (regulating valve) should be installed in the discharge
line. The check valve placed between the pump and the gate valve is to protect the pump from excessive
pressure and to prevent water running back through the pump in case of failure of the driving machine.
Discharge piping should be provided with a sluice valve adjacent to the delivery flange to control the
discharge, if required.
VACUUM EQUALISING LINE (AND LIQUID LINE)
(SEE FIGURE 3)
If the pump draws from a system under vacuum an equalising pipe must be carried from the highest point of
the suction line, however, as close to the suction flange of the pump as possible, to the top of the feed tank
to keep gas bubbles that might have been entrapped in the flow from entering the pump. The line should be
fitted with an isolating valve which should be closed only for maintenance work on the pumpset.
Apply sealing liquid (external sealing) to the shaft seal cage to prevent entry of air in the case of pumps with
packed stuffing box. It is convenient to tap the sealing liquid from the delivery line above the non-return valve.
STRAIGHT EDGE
Figure 2
MEASURING
WEDGE