Symbolic meaning：
DEL,DFLT1/2/3/4/5/8/12/20
electric machinery：
The motor is fully enclosed, air-cooled secondary standard motor
Protection grade: IP55
Insulation class: F
Standard voltage: 50 Hz: 1 x 220-230 / 240V
3 X 200-230/346-380V
3 X 220-240/380-415V
3 X 220-255/380-440V
Motors with other voltages are available as required.
Single phase motors are available from 0.37 to 2.2 kW.
Typical applications：
DFL (T) is a kind of multi-function product, which can transport various media from tap water to industrial liquid, suitable for different temperature, flow rate and pressure range.
Dflt is suitable for non corrosive liquids and DFL is suitable for mild corrosive liquids.
Water supply: filtration and transportation in water plant, water supply in different areas and pressurization in high-rise buildings.
Industrial pressurization: process water system, cleaning system, high pressure flushing system and fire protection system.
Industrial liquid transportation: cooling and air conditioning system, boiler feed water and condensation system, machine tool matching, acid and alkali.
Water treatment: filtration system, reverse osmosis system, distillation system, separator, swimming pool, etc.
Irrigation: farmland irrigation, sprinkler irrigation, drip irrigation, etc.
Product range：
performance curve：
All curves are based on the measured values of the motor at a constant speed of 2900rpm or 2950rpm.
The curve tolerance is in accordance with iso9906, Appendix A.
The test adopts 20c water without air, and the kinematic viscosity is lmm2 / s.
The use of the pump should refer to the performance range of the thick line, so as to prevent overheating caused by too small flow or overload of the motor caused by excessive flow.
working pressure：
The following figure shows the limits of pressure and temperature, which must be within the range shown.
Pump description：
DFL (T) is a non self-priming vertical multi-stage centrifugal pump equipped with standard motor. The motor shaft and pump shaft are directly connected by coupling. The pull rod is externally simplified with nuts. The flow passage parts are fixed between the bracket and the water inlet and outlet. The pump inlet and outlet are on the same straight line at the bottom of the pump.
The pump can be equipped with intelligent protector as required to effectively protect the dry running, phase loss and overload of the pump.
Altitude and ambient temperature：
When the pump operates at ambient temperature greater than 40 ° C or altitude greater than 1000m, the motor output power P2 will be reduced, so the motor power of the pump should be increased under the above conditions.
Minimum inlet pressure NPSH：
If the pressure in the pump is lower than the steam pressure of conveying liquid, cavitation may occur. In order to avoid cavitation, ensure that there is a minimum pressure at the inlet side of the pump. When h [M] is large, it can be calculated as follows:
H=Pbx 10.2-NPSH-Hf-Hv-Hs
Pb = atmospheric pressure [bar]
(atmospheric pressure can be set to 1bar)
In a closed system, Pb is the system pressure [bar]
NPSH = net positive suction head [M]
(it can be read from the NPSH curve where the pump may reach a high flow rate)
HF = pipeline loss at inlet [M]
HV = steam pressure [M]
HS = safety margin = minimum 0.5m head
If the calculated value of H is positive, the pump can operate at a large suction head H.
If the calculated h is negative, there must be a head of minimum inlet pressure H.
