. Installation
1.1. Installation of common baseplate
Installation and centering of the pump should be performed by skilled workers. Improper installation and centering would cause various troubles during the pump running. When the pump and its driver are shipped as directly coupled on the common baseplate, they have already been leveled and centered completely at our fabrication shop before shipment.
However, install the common baseplate (with pump and driver properly in the sequence given below and recheck the level and centering of pump and its driver).
(1) Prepare packers (steel wedges) and several kinds of 1 mm ~ 0.1 mm thick levelling shims.
(2) After complete cure-up of the pump foundation, place and position packers on the foundation at the both sides of each anchor bolt seat so that the common bed can be put on the packers later on. Thereafter, grout concrete on the foundation floor at each packer position and re-place and reposition the packers on the concrete. In this case, don't fail to keep each packer right horizontal after adjusted by use of a level. The height of each packer is to be fine-adjusted by insertion of shim(s) when the common bed is installed thereon. Accordingly, at this stage only horizontality adjustment of the packers is sufficient.
(3) After complete cure-up of the concrete with packer on, temporarily install the common baseplate (with pump and driver) on the packers and check the center height of the pump. Furthermore, hold a level on the dis - charge flange to make fine-adjustment of the pump horizontality in both axial and crosswise directions by inserting previously prepared levelling shims between the baseplate and each packer.
(4) After the pump was positioned and levelled, make pre-center alignment between the pump and the driver using a centering jig (refer to 1.2 for the detail). In this case, recording the numeral date on pre-alignment will be helpful when the direct coupled condition is checked.
(5) After pre-centering, grout concrete in each anchor bolt holder.
(6) After complete cure-up of the concrete in each anchor hole, tighten each anchor bolt nut with unifor m tightening torque. In this case, check and readjust the center alignment between coupling halves, based on the recorded numeral pre-alignment data.
(7) After the above check, grout mortar under the common bed till it reach es entirely all the corners of the bed s o that no cavity exists under the bed.
(8) After completion of all the above items, connect the suction pipe and discharge pipe to the respective flanges of the pump
1.2. Direct Coupling
The pump shaft and the driver shaft must be centered in line. Therefore, make centering in the following procedure without fail.
(1) For centering of the coupling,
put a straightedge
on the both coupling halves and insert a wedge gauge in the axial clearance between the coupling halves, as illustrated in Fig. 2, to check run-out
of the coupled shafts.
. 
(2) In this case, measure the concentricity and parallelism of the coupling halves (the both shafts) respectively at
4 points spaced at 90. The specified accuracy shall be within 0.1 mm respectively.
(3) Check the driver’s rotating direction without fail, before connecting one coupling half (pump side) and other coupling half (driver side) together. The correct rotating direction of the pump is shown with an arrow mark on the side face of the bearing pedestal, that is, clockwise direction viewing from the driver side.
(4) If the rotating direction is correct, connect two coupling halves together.
(5) Further, if the temperature of pumping liquid exceeds the normal temperature range of changes widely during pump running, the direct coupling will possibly deviate a little. In such case, therefore, use the coupling with large flexibility.
1.3. Piping
After completion of the direct coupling work, the suction and discharge pipes must be connected to the respective flanges of the pump. Perform the piping connection with good care for the following items.
(1) When connecting the suction and discharge pipes, take proper measure to prevent piping load from directly acting on the pump. Direct load to the pump by piping would cause trouble.
(2) The suction line must be installed in upward slope (about 1/50) toward the pump prevent air leak and air pocket in the case of suction lift. And it must be installed in downward slope reversely in the case of forced suction.
(3) Take to minimize various losses of the suction pipe and avoid sudden changes of cross -section and use of abrupt bends in the suction piping. Select the pipe size such that the flow velocity in the pipe does not exceed 3 m/s.
(4) When the suction pipe size is different from the pump suction nozzle size, use an eccentric tapered pipe to connect
(5) When a sluice valve is installed on the discharge line, located the valve as close as possible to the discharge nozzle of the pump. Further, when a check valve and a sluice valve are provided o the discharge line, locate the check valve between the pump discharge nozzle and the sluice valve.
(6) In case of starting operation of a plant for the first time, various foreign matters remain in its pipe line and may
possibly flow into the pump. In such case, therefore, provide a strainer on the suction line for complete removal of foreign matters. The strainer used shall have the passing area equal to 3 ~ 4 times the sectional area of the suction pipe. If the strainer is clogged with foreign matters during the pump running, readings of the suction line pressure gauge will fluctuate. Sometimes, clean the strainer to remove foreign matters.
(7) When external flushing water piping is provided, clean adequately the flushing water pipe before connecting.
(8) The temperature of pumping liquid significantly different from the atmospheric temperature would cause the pipe line to shrink or expand. In such case, install a flexible pipe, etc. on the pipe line to prevent the load by shrink age o the pump.
(9) After completion of the piping work, recheck that the pump is free from abnormal load by piping as well as free from
alignment deviation, and make re-adjustment when required upon rechecking.
2. Operation
2.1. Starting
(1) Before starting the initial operation after installation, observed the following check items and, if anything abnormal is found, take necessary corrective action in accordance with this manual.
(1) Are the pump and the suction pipe filled up with pumping liquid ?
(2) Is the driver's rotating direction correct ? (Pump rotates clockwise viewing from the driver's side) (3) No abnormal in the direct coupling ?
(4) No abnormal load to the pump by piping ?
(5) Is the flushing pipe connected properly and the water flow rate proper ? (6) Are the suction valve fully opened and the discharge valve fully closed ?
(7) Isn’t the gland packing tightened irregular or too excessively? Also, isn’t there any abnormal leakage
from the gland packing ?
(8) Can the pump be turned lightly by hand ? Isn’t there any t ouch of contact in the pump ?
(2) If nothing abnormal is found upon checking the above items, turn on the driver’s start switch and of it immediately to check that the pump rotates smoothly and shut downs quietly.
(3) If normal rotation of the pump is confirmed, gradually open the discharge valve up to the specified running speed. W hen leakage from the gland is much, re-tighten the gland packing with equal torque for adjustment
(4) If the pump continues running with the discharge valve fully closed, the liquid temperature in the pump will rise, causing trouble of the pump. In such case, shut down the pump immediately without fail.
(5) W hen starting the pump after long term shut –down, recheck the above check items (1), and (5) then (8) to verify that the pump is abnormal-free.
2.2. Shutdown
Follow the procedure given below for shutting down the pump.
(1) Gradually close the discharge sluice valve up to full close position. However, it may be left as opened providing that a check valve is included in the discharge pipe and the back pressure is sufficient.
(2) Turn of the driver ‘s stop switch. At the same time, check that the pump rotational speed declarat ion smoothly and stops quietly.
(3) Stop external flushing, if any.
(4) Fully close the suction valve when the pump is kept as shutdown for long time.
(5) When there is a possibility of freezing in the pump, completely drain out the pumping liquid from the volute casing. (Complete drain of the liquid in the line is more safety).
2.3. Operation and Maintenance
2. 3. 1. General
The pump must run quietly without abnormal vibration all the times. Therefore, carefully observe the following check items while the pump is in running and, if anything abnormal is found, shut down the pump imm ediately and search the cause.
(1) Does the suction pressure fully satisfy the pump required NPSH (NPSH req.) ? (2) Is the specified discharge pressure satisfied ?
(3) Isn’t the driver in overload running ?
(4) Are the both suction pipe and volute casing filled up with pumping liquid and the discharge valve f ully opened in the pump running ?
(5) Is the bearing temperature normal ? (no abnormal temperature rise ?)
(6) Is leakage from the gland proper ?
(7) Is the pump running with no abnormal noise and no vibration ?
2.3.2. Shaft seal
The shaft seal is available in two different types of gland packing and mechanical seal. The descriptions here under covers the gland packing seal type. Refer to Chapter IV for the detailed instructions of the mechanical seal.
The gland packing insertion space in the casing cover is designed to be equivalent the either five packing rings
(4610) or three packing rings plus one lantern ring (4580).
The gland bush (4540) is of split type as to facilitate insertion of the packing rings. (1) Gland packing without lantern ring
The seal type is applied to the suction pressure of 0,5 kgf / cm2G and over or the handling of odorous liquids (e.g. ammonia water and benzine, benzol or lubricant for outdoor use, etc.). In such cases, self flushing or external flushing is not applied to the gland packing.
(2) Gland packing with lantern ring
This seal type is applied to the following cases.
o Clean liquid under suction pressure of 0.5 kgf/cm2G or under suction lift.
o Pumping the liquid from vacuum tank.
o The pump shaft and its gland packing must be protected from abrasion for handling liquid containing abrasive component, (e.g. handling of sewage and the like).
In such cases, either self flushing or external flushing by proper liquid is applied to the gland packing as des cribed below.
(a) Self-flushing
In this case, flushing liquid is conducted into the lantern ring through a passage provided in the casing cover.
(b) External flushing
This flushing system is applied to such case that inclusion of external liquid in the pumping liquid is allowed. In this case, same of the flushing liquid flows into the volute casing and the remaining is discharged into the atmosphere through the clearance in the gland bush.
In the case of the gland packing shaft seal, packing ring (4610), lantern ring (4580) and gland bush (4540) ar e inserted in the stuffing box. In this case, the outside surface of shaft protecting sleeve (5240) must keep smooth all the times.
Any flaw on the shaft protecting sleeve surface or irregular tightening and over -tightening of the gland (4520)
would cause the shaft seal to be overheated and the packing rings to deteriorate earlier than expected.
When the packing rings are replaced with new ones, packing material highly resistant to pumping liquid and its temperature must be used. Before replacement, clean the lantern ring, gland bush and gland and, cut the packing material to the specified dimension with a proper cutter using the cutting jig illustrated in Fig. 4. Thereafter, insert the packing rings, one by one into the stuffing box so that the butt ends of each ring are offset by 90° from each other on
the shaft protecting sleeve. (Refer to Fig. 5.)
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