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Vertical Multistage Centrifugal Pump

QDL/QDLF2 Series QDL/QDLF4 Series QDL/QDLF8 Series QDL/QDLF16 Series QDL/QDLF32 Series

I Product characteristics for Vertical Multistage Centrifugal Pump

Vertical Multistage Centrifugal Pump1
  1. Low noise: Install the model number of Y2 electric motor,the circulate is steady,and low noise
  2. Without leakage: Specially selected mechanical seal and science processes a craft,professional technical assurance,carry out the pursue of"without leakage"
  3. Simple to demolish and install: Rigid couplings,spline shaft design,the weight ease 50% than the pumps,and the operability is better
  4. Install is convenient: Enter of water and out of water are on the same level,the Lower to the tube road request,the the and tube road the s usage is more dependable,the stability is higher
  5. The investment of pump - house - building is less: At the orginally foundation of vertical
  6. multistage pump go forward to go an improvement,the the physical volume is small,covering area little
  7. Avoid the second-pollution of the fluid matter: Inducer and shaft are made of stainless steel,overcome the weakness of the cast-iron pump,promise the quality of the fluid matter
  8. Have no rust eclipse harassment: The use cylinder of stainless steel,better adapt various environment,never rusty
  9. The life span is longer: The material hurtles of stainless steel are pressed,the weld impeller,the weight is light,balance good,circulate a stability
  10. Support expenses low: The Adopt the water-lubrication-bearing design,Circulate more dependable,need not to lubriicate to maintain
  11. Efficiently and economize on energy: The More excellent water power model,the smooth of over flow a parts,raised a machine efficiency consumedly

II Performance scope for Vertical Multistage Centrifugal Pump

Vertical Multistage Centrifugal Pump2

III Product range for Vertical Multistage Centrifugal Pump

Rated flow [m3/h] 2 4 8 16 32
Rated flow [1/s] 0.56 1.1 2.2 4.4 8.9
Flow range [m3/h] 1~3.5 1.5~8 5~12 8~22 16~40
Flow range [1/s] 0.28~0.97 0.42~2.2 1.4~3.3 2.2~6.1 4.4~11.1
Max.pressure [bar] 23 21 21 22 26
Motor power [kw] 0.37~3 0.37~4 0.75~7.5 2.2~15 1.5~30
Temperature range [ ] -15~+120
Max.efficency 46 59 64 70 76
QDL pipe connection          
DIN Flange DN25 DN32 DN40 DN50 DN65
Pipe thread        

IV Application scope for Vertical Multistage Centrifugal Pump

QDL/QDLF is a king of multifunctional products. It can be used to convey various medium from tap water to industrial liquid at different temperature and with different flow rate and pressure. QDL type is applicable to conveying-corrosive liquid,QDLF is suiable for slightly Corrosive liquid. Water supply:Water filter and transport in water works, boosting of main pipeline, boosting in high-rise buildings. Industrial boosting:Process fiow water system, cleaning system, High-pressure washing system, fire fighting system.
Industria liquid conveying: Cooling and air-conditiong system, Boiler water supply and condensing system, machine-associated purpose, acids and alkali.
Water treatment:Ulrafitation system, reverse osmosis system, Distillation system, separator, swimming pool
Irrigation:Farmland irrigation, spray irrigation, dripping irrigation.

V Operation conditions for Vertical Multistage Centrifugal Pump

Medium :Thin,clean,noon-flammable and non-explosive liquid containing No solid granules and fibers.
Liquid temperature type:-15 ~+70
Hot water type:+70 ~+120
Ambient temperature:up to +40
Altitude:up to 1000m

VI Vertical Multistage Centrifugal Pump

QDL/QDLF is a kind of vertica non-self priming multistage .Centrifugal pump, which is driven by a standard electric motor. The motor output shaft directly connects with the pump Shaft through a coupling. The pressure-resistant cylinder and flow passage components are fixed between pump head and in-located at the pump bottom at the same plane. This kind of pump can be equipped with an intelligent protector to effectively prevent it from dry-running, out-of-phase and overload

VII Electric motor for Vertical Multistage Centrifugal Pump

Full-enclose air-blast two-pole standard motor. Protection class:IP55;Insulation class:F
Standard voltage:50Hz:1 20-230/240V;3 00-220/346-380V;3 20-240/380-415V;3 80-415V

VII Electric motor for Vertical Multistage Centrifugal Pump

The maximum inlet pressure is the table below. But the actual inlet pressure plus the valve close pressure allowable working pressure

Max inlet pressure
QDL,QDLF2-20 6[bar]
QDL,QDLF2-30~2-110 10[bar]
QDL,QDLF-130~2-260 15[bar]
QDL,QDLF4-20 6[bar]
QDL,QDLF4-30~4-100 10[bar]
QDL,QDLF4-120~4-220 15[bar]
QDL,QDLF8-20/1~8-60 6[bar]
QDL,QDLF8-80~8-200 10[bar]
QDL,QDLF16-20~16-30 6[bar]
QDL,QDLF16-40~16-160 10[bar]
QDL,QDLF32-10-1~32-20-2 3[bar]
QDL,QDLF32-20~32-40 4[bar]
QDL,QDLF32-50-2~32-100 10[bar]
QDL,QDLF32-110-2~32-140 15[bar]

IX Max Working Pressure

Curve number
QDL,QDLF2-20~150 1
QDL,QDLF2-180~2-260 2
QDL,QDLF4-20~4-140 1
QDL,QDLF4-160~4-220 2
QDL,QDLF8-20/1~8-120 1
QDL,QDLF8-140~8-200 3
QDL,QDLF16-20~16-80 1
QDL,QDLF16-100~16-160 3
QDL,QDLF32-10-1~32-70 1
QDL,QDLF32-80-2~32-120 4
QDL,QDLF32-130-2~32-140 5

The following figure shows the limitation of pressure and temperature, which shall be kept within the region as shown in the figure.

Vertical Multistage Centrifugal Pump3

X Performance curve

Following conditions are suitable for the performance curves shown bellow
All the performance curves are based on the measured values of a motor 3 80~415V at a constant speed of 2900 rpm.
Curve tolerance in conformity with ISO9906,appendix A.
Measurement is done with 20 air-free water, kater, kinematics viscosity of 1mm2/s.
The operation of pump shall refer to the performance region indicated by the thickened curve to prevent overheating due to too small flow rate or overload of motor due to too large flow rate.

XI NPSH Minimum inlet pressure NPSH

In case that the pressure in pump is lower than the stem pressure used to convey liquid, the capitations will occur. To avoid cavitations, a minimum pressure at the inlet side of the pump shall be guaranteed. The Maximum suction stroke can be calculated with following formula: H=Pb 0.2-NPSH-Hf-Hv-Hs
Pb=atmosphere pressure [bar]
(can be set as 1bar)
In a closed system, Pb means system pressure[bar]
NPSH=Net positive suction head[m]
(It can be read out from the point of possible max, flow rate shown on NPSH curve)
Hf=Pipeline loss at the [m]
Hv=Steam pressure[m]
Hs=Safety margin=Minimum 0.5m delivery head
If the calculated result H is positive, the pump may run under the max. Suction stroke H.
In case the calculated result H is negative, a delivery head of min. Inlet pressure is necessary

XII Operation in parallel

Connecting several pumps in parallel running will benefit much more than running a single large pump. Applicable to different working states necessary in a variable flow system. Increasing the possibility of water supply when the pump is in failure. Because in case of pump failure, only part of the system flow is effected.

Vertical Multistage Centrifugal Pump4
Check and ensure that the pump is not at cavitations state.
Vertical Multistage Centrifugal Pump5
Two pump or more can be connected in parallel running if necessary.
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