2020-11-01 17:54:13 Source: sand dredge pump-slurry pump parts-China Do Pump
What are questions of slurry pump and related solutions?
DO PUMP is a professional manufacturer of submersible sand pumps. Submersible sand pumps are also known as submersible dredging pumps, submersible slurry pumps, submersible heavy medium pumps, hydraulic submersible sand pumps, and electric submersible sand pumps.
The basic composition of a slurry pump: motor, coupling, pump head (body) and frame (horizontal).
ρ: Density of liquid delivered by slurry pump (kg/m3)
γ: The gravity of the liquid delivered by the slurry pump γ=ρg (N/ m3)
g: acceleration due to gravity (m/s)
Mass flow Qm=ρQ (t/h or kg/s)
What is the rated flow, rated speed, and rated head?
Answer: The slurry pump is designed according to the working performance parameters of the set slurry pump, and the best performance achieved is determined as the rated performance parameters of the pump, which usually refers to the specified performance parameters in the product catalog or sample
Parameter value.
For example: 50-125 flow rate 12.5 m3/h is the rated flow rate, head 20m is the rated head, and the speed of 2900 rpm is the rated speed
What is cavitation margin? What is suction range? The respective units of measurement represent letters?
Answer: When the slurry pump is working, the liquid will generate vapor at the inlet of the impeller due to a certain vacuum pressure. The vaporized bubbles will produce vapor on the impeller and other metal surfaces under the impact movement of the liquid particles.
Erosion, thereby destroying metals such as the impeller. At this time, the vacuum pressure is called the vaporization pressure. The cavitation margin refers to the excess energy that exceeds the vaporization pressure per unit weight of the liquid at the pump suction port. Unit use
Marked in meters, use (NPSH)r. The suction stroke is the necessary NPSH Δh: the vacuum degree of the pump allowed to suck liquid, that is, the allowable installation height of the pump, in meters.
Suction range = standard atmospheric pressure (10.33 meters)-cavitation margin-safety amount (0.5 meters)
The vacuum height of the standard atmospheric pressure energy pressure pipeline is 10.33 meters.
For example: a certain slurry pump must have a cavitation margin of 4.0 meters, what is the suction range Δh?
Solution: Δh=10.33-4.0-0.5=5.83 meters
What is the characteristic curve of a slurry pump? How many aspects does it include? What's the effect?
Answer: Usually the curve representing the relationship between the main performance parameters is called the performance curve or characteristic curve of the centrifugal pump. In essence, the performance curve of the centrifugal pump is the outside of the law of liquid movement in the pump.
The form of expression is obtained through actual measurement. Characteristic curves include: flow-head curve (Q-H), flow-efficiency curve (Q-η), flow-power curve (Q-N), flow-cavitation margin curve
(Q-(NPSH)r), the function of the performance curve is to find a set of relative head, power, efficiency and cavitation margin values on the curve for any flow point of the pump. This set of parameters is called
Working state, referred to as working condition or working condition point, the working condition at the highest efficiency point of the centrifugal pump is called the best working condition point, and the best working condition point is generally the design working condition point. The rated parameters of general centrifugal pumps are the design conditions
The point coincides with or is very close to the best operating point. It is important to know the performance parameters of the pump to run in the practical efficiency range, which saves energy and can ensure the normal operation of the pump.
What is the full performance test bench for slurry pumps?
Answer: The equipment that can accurately test all the performance parameters of the pump through precision instruments is the full performance test bench. The national standard accuracy is Class B. The flow rate is measured with a precision worm wheel flowmeter, and the head is measured with a precision
