DIN 24255 High Pressure End Suction Centrifugal Pump , Fire -
Fighting Water Centrifugal Pump
A. For wastewater treatment plant
B. For building water - supplying
C. For wastewater system
Key points for GHS accessories
A. PUMP CASE:
foot support structure and spiral volute chamber, with volute
chamber, foot, influent flange and discharge flange cast into an
integrity. The flanges may be drilled accordance with international
stand ISO 2084 DN16 or as requirement.
Closed impeller designed in the excellent hydraulic model to
guarantee pump performance and efficiency. The dynamic balance test
shall be conducted.
C. SUSPENSION FORK:
The suspension fork is installed with bearing inside. There are
totally 6 bearing specifications for the whole series. The bearings
shall be lubricated by lubricating oil (for some specifications) or
A. Designed by following DIN24255
B. Materials are variable based on customer demand
C. The pump rotates in the colckwise direction if viewed from the
D, Easy operation and maintenance.
E. The suction and discharge pipes no need be taken down for pump
cover and impeller disassembly.
F. The GHS parts are universally replaceable. The whole series have
46 models that only adopt six types of shaft. All parts may be
GHS structure drawing
|4||Impeller flat key|
|8||Pump body O-ring|
|15||Pump connection flat key|
LOCATION OF UNIT
The pump should be place as near the liquid source as practical so
that a short direct suction
pipe may be used. The pump should be accessible for inspection and
repair work and
headroom be provided for crane. hoist or tackle if the pump is
Both the suction and discharge lines should be independently
supported near the pump so that
no strain will be placed on the casing.
The suction line should be as short and straight as possible and
contain a minimum number of
bends. Any bends necessary should have large radii. Generally the
suction pipe is made one or
two sizes larger than the pump suction branch. For pumps operating
with suction lift no valves
other than a foot-valve should be placed in the suction line. All
these precautions ensure that
maximum available suction head on the pump. Reducers must be
eccentric if installed in a
horizontal position (Fig. I). A straight taper reducer (Fig. II)
should not be used in a horizontal
suction line, because it may form an air pocket (IIA) in the top of
the reducer and the pipe.
It is very important to have the suction line airtight and to avoid
undulations in which air may
collect and destroy the vacuum. Where adverse suction conditions
may cause the pump to lose
its prime, the use of an external automatic priming device such as
a vacuum pump is
Ensure that the system is free from foreign matter such as pipe
scale, welding beads, dirt, etc.
It is suggested to flush the whole system before going into
operation. If possible use a
temporary suction screen for removal of material in the pipe
For a give suction lift, suction capacity depends on the
temperature of the liquid. For water
70℃(106°F)or above, care should be taken to ensure that enough
pressure is available at the
impeller entry to prevent vaporization.
Should have a fee area of at least one and a half times the area of
the suction pipe.
An efficient strainer should be provided to prevent foreign matter
from being drawn into the
pump or choking the foot valve.
When there is any refuse such as sticks, twigs, leaves, etc., in
the water, a larger outside
screen, or a large basket strainer. This screen should have
sufficient openings to keep the flow
through it below 0.6m (2 feet) per second.
Generally the discharge piping is made one size larger than the
pump discharge branch size.
The discharge line should be short and direct with the least number
of bends and fittings, thus
minimizing the head lost by friction. A non-return valve and
discharge valve are usually placed
in the discharge line. The non-return valve is to protect the pump
from excessive back
pressure and reverse rotation of the unit, and to protect back flow
into the pump incase of
stoppage or failure of the driver. The discharge valve is used to
regulate the flow. The
non-return valve Is placed between the discharge valve and the pump
so that it may be
inspected or repaired without emptying the discharge line.
The foundation should be substantial to reduce vibrations and rigid
enough to avoid any
twisting or misalignment.
The pump driver, if supplied, is correctly aligned on its base
plate at the factory. A certain
amount of deformation of the base plate is possible during transit
and it is therefore essential
to check alignment before going into operation. The pump shaft
should be checked for angular
and parallel alignment. A flexible coupling will not compensate for
alignment results in vibration and excessive wear on the bearings,
sleeve or shaft and wearing.
The check for angular alignment (Fig. III) should be made by
inserting a pair of inside calipers
or taper gauge (IIIA) at four points, spaced at 90℃ intervals,
between the coupling faces
which must be within 0.07mm (0.003’’). A check for parallel
alignment (Fig. III) is made by
placing a straight edge (IIIB) across the coupling rims at the top,
bottom and at both sides.
The unit will be in parallel alignment when the straight edge rests
evenly on the coupling rim at
A space of approximately 25mm (1’’) should be left between the base
plate and top of the
foundation to be filled with grouting. After the grouting has dried
the foundation bolts should
be firmly tightened and alignment re-checked.