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• Pipe connections should be made with the flanges. Flange bolts should be made of proper material
and in proper size. The flange bolts should be inserted between the flange bolts and centred in such
way that it would not impair flow section.
• In case of excessive vibrations and systems operating with hot liquids, expansion parts should be
used in order that any extra forces that may arise from thermal expansion are not transferred to the
pump.
• Materials such as welding burrs, metal particles, sand and oakum arising from production of fhe
piping system may remain in the pump and give damage to the pump. The suction and delivery
flanges should be sealed blind washers in order to prevent such materials from entering into the
pump during the assembly operations. After assembly, all pipe parts should be removed, cleaned,
painted and reassembled. If dirt-retainer is used on the suction side of the pump, the dirt-retainer
should be cleaned after working for several days.
4.4.2- Suction pipe
• The suction pipe should be definitely watertight and should not be arranged in a way to cause
formation of air pockets. In other words, if it is supplied from a reservoir higher than it (system with
elevated suction/supply), the suction pump should be slightly declined towards the pump; and if the
pump is supplied from a reservoir lower than it (system with suction depth), than the suction pipe
should be gradually inclined slightly towards the pump.
Figure 2a and 2b
• In order to keep the loss from friction, sharp elbows should not be used; and abrupt change of
direction and section should be avoided and suction pipe should be made short as far as possible. If
it is required to make change of section on a horizontal suction pipe, an eccentric conical spacer with
its flat side on the top should be used.
4.4.3- Delivery pipe
• A flow control valve should be connected on the delivery pipe, near the pump as far as possible in
order to adjust the flow rate and delivery head.
• If the delivery head of the pump is more than 10 m or the delivery line is quite long, a check valve
should be connected between the pump and flow rate adjusting valve on the delivery pipe in order
to protect the pump against water hammers when stopping the pump or prevent backflow.
• If the pump is supplied from a reservoir higher than it, an insulation valve should be
used to keep the axis on the suction pipe horizontally. This valve should always be open
when the pump operates and it should never be used as flow rate adjusting valve
(Caution: Throttle of the valve may cause the pump to operate with cavitation).
ATTENTION
