The self-priming sewage pump type WFB mainly consists of pump body, impeller, pump cover, blade guide, sub-impeller, pump shaft, connection support, electric air control valve, among other parts. The interior of the pump body consists of a suction chamber, liquid storage chamber, and gas-liquid separation chamber. When starting normally, the impeller sucks the liquid stored in the suction chamber along with the air in the suction pipe. The mixture of liquid and gas is thrown by the centrifugal force of the impeller at high speed into the gas-liquid separation chamber through the blade guide. Due to the sudden reduction in speed, the gas and liquid separate by density difference; the lighter gas separates and is expelled outside the pump. The degassed liquid returns to the working chamber and mixes again with the air sucked from the inlet pipe. Under the rotation of the impeller, a certain degree of vacuum is created at the pump inlet, thus achieving self-priming. Due to its unique air expulsion function, this pump can transport liquids with gas without the need to install a bottom valve. The pump is equipped with an "electric air control valve" that closes during operation to achieve sealing; when stopping, the valve opens, destroying the vacuum in the suction pipe and preventing the liquid in the pump chamber from flowing back into the pipe due to suction effect, maintaining enough liquid in the chamber to continue the self-priming process, thus achieving "the first priming and permanent self-priming."
1. Characteristics of the self-priming sewage pump type WFB
The self-priming sewage pump has reliable sealing, using a leak-free sealing device composed of dynamic sealing and auxiliary sealing. It replaces the traditional packing sealing and mechanical sealing, completely solving problems such as "leaks, escapes, drips, and losses" of traditional seals. It is an ideal product to replace long shaft submersible pumps, submersible pumps, and submersible sewage pumps.
2. Advantages of the self-priming sewage pump type WFB
The seal-less self-priming pump has no friction or wear in the sealing device during operation, with a service life more than 10 times greater than traditional products. It adopts the vacuum pump principle for stable and reliable self-priming, especially with the "electric air control valve" that truly achieves the first priming and permanent self-priming. The pump unit has low vibration, low noise, flexible mobility, and easy disassembly. It has superior control functions and can be integrated with related control systems to achieve high automation.
2. Description of the associated motor
For proper motor selection, we have taken the experience of developed countries and divided the working conditions into three levels A, B, and C. The motor power in this catalog is based on level A. If used in conditions B or C, the motor power can be reduced according to the specific situation.
Classification of working conditions:
Working condition level A: continuous operation, with the three parameters of suction, flow, and lifting height meeting the standards;
Working condition level B: continuous operation, with two of the three parameters meeting the standards;
Working condition level C: intermittent operation, with one of the three parameters meeting the standards.
Note: If there are special requirements, please contact our company, we will be happy to design and manufacture for you (WFB series pumps).
Instructions for use of the sewage pump:
(I) Part of the pump
(1) After installation, completely fill the medium from the priming port for the first priming; it is not necessary to prime in subsequent uses. Please tighten the cap of the priming port to prevent air leaks that affect self-priming.
(2) Adaptable particle indicators (unit mm)
Suction port diameter: less than 50, 50～100, 100～200, 200～300, 300～400, more than 400
Particle diameter: <5, 5～8, 8～12, 12～16, 16～20, 20～25
(3) The supplied filter mesh must be installed to prevent particles exceeding the limit from being sucked in, which would damage the water pump and affect the self-priming function.
(4) It is prohibited to use water as drainage when transporting concentrated sulfuric acid to avoid personal accidents and equipment damage.
(5) Before starting, it must be checked that the water pump shaft is flexible and verify the direction of rotation by pulses to ensure it matches the direction mark.
(6) The weight of the suction and discharge pipes should not be supported on the pump's outlet flange, but fixed to a support (the user must provide the support). The pipe connections must be airtight and leak-free; otherwise, it will affect the self-priming function, flow rate, and lift height.
(7) When draining liquids with crystals or sediments, if the self-priming vertical pump has been stopped for a while, the drainage liquid must be emptied from the pump body through the drain port to prevent crystals and sediments from remaining inside and causing damage upon restarting. When reusing, follow the "drainage" procedure from point (1). If draining only once every few days, it is recommended to run program A from the installation and operation diagram every 24 hours for 20 minutes to reduce the formation of crystals and sediments.
(8) If the pump has been stopped for a long time, before starting, check from the "drain port" that there is enough drainage liquid; if not sufficient, complete it before starting.
(9) During the transfer of liquids, the three parameters of flow rate, lift height (pressure), and suction height must be strictly maintained within the specified range for the selected model. Otherwise, the motor will suffer overcurrent fluctuations that will affect normal operation.
(10) If used in tanks or containers below ground level, refer to the installation and operation diagram (I).
(11) If the pump is placed below the liquid surface, refer to the installation and operation diagram (II). The positive pressure water inlet type pump has the unique advantages of frictionless sealing during operation, no wear, no leaks, and long service life. To prevent leaks due to static pressure after stopping the pump, a stop sealing device or an electromagnetic valve synchronized with the pump at the inlet is used.
(12) If supplying liquid to an elevated tank or water tower, refer to the installation and operation diagram (III).
(13) When draining media that generate bubbles, with high specific gravity, large lift height, and high static pressure in the water column of the outlet piping system, to accelerate the degassing speed and shorten the self-priming time, refer to program B of the installation and operation diagram (IV).
(14) If used in fire-fighting systems that use pond water, to minimize the water discharge time, refer to the installation and operation diagram (V). Additionally, it is not recommended to increase the diameter of the pipes, as the liquid speed in the inlet pipe is already controlled according to national standards, and increasing the diameter would directly affect the discharge time.
(15) When replacing pipeline pumps and in closed circulation systems, refer to the installation and operation diagram (II).
(I) Part of the pump
(16) The drain port, emptying port, self-priming degassing device, outer cover, and heat source inlets and outlets are not related to installation dimensions or connection to the system. The "self-priming degassing device" is only activated when the vertical lift height is high and the static pressure in the water column of the outlet piping system is large; under normal process conditions, it is not necessary to activate it.
(17) This pump uses the principle of self-priming by vacuum generated by air separation. If designed for environments with absolute output speed requirements, the suction pipe diameter should not be increased to avoid affecting the suction speed (except in environments without absolute speed requirements).
(18) The self-priming long-distance suction pump manufactured by this unit can adapt to special environments with horizontal suction pipe distance ≤150 meters and vertical height ≤7 meters to transport various liquids. Before starting, in addition to following the usage instructions, it must be operated according to the design plan and the characteristics of the medium and process: the horizontal suction pipe must be completely filled with liquid; otherwise, the air purge time will be too long, causing heating of the drainage liquid in the pump chamber and undesirable consequences.
(19) The heat source for antifreeze pumps must be hot water or steam, and the temperature inside the pump chamber must not drop below 5℃ throughout the day (heating is not necessary during normal transfer operations).
(II) Part of the electric air control valve
(1) Non-specialized electrical personnel should not open the cover to avoid accidents from electric shock.
(2) When installing after upgrade or repair, ensure that the cable is firmly connected to the pump motor terminals.
(3) The connection thread with the pump must be tightened firmly to avoid air leaks; otherwise, it will affect self-priming.
(4) It is not recommended to use this valve in the two environments (11) and (15) of the pump.
(III) Part of the automatic control device
For users with automatic control devices, a separate circuit diagram will be provided. Please pay attention to the following:
(1) Non-specialized electrical personnel should not open the panel door to avoid accidents from electric shock.
(2) This device operates with three-phase power, voltage 380V, frequency 50Hz, and circuit protection must be installed on the input line.
(3) After connecting the power supply, press the button ●On●Off to the on position; the power indicator will light up and the device will be in standby mode.
(4) To select the operating mode, use the automatic button ●Stop●Manual. The manual start and stop buttons are only applicable in manual mode. In automatic mode, the device will operate automatically according to the upper and lower level sensors.
(5) This device has two types of installation: "wall mount" and "floor mount". For powers below 30kW, wall mounting with direct start is used; for powers of 37-75 kW, floor mounting with star-delta start is used; for powers above 90kW, floor mounting with autotransformer start is used. The starting mode can also be determined according to the user's needs.
This device is not connected with other systems, so no external dimensions of the switch are provided.
(6) Carefully protect the sensor cables to avoid damage caused by the user.
(7) When adjusting the rotation direction of the pump motor, do not change the internal connection order of the device, but swap the wires inside the motor connection box.
(8) When setting the upper and lower limit position of the sensor, refer to the "Installation and Operation Diagram" (one) or (three).
Helpful tip: For performance parameters, refer directly to the water pump selection page.
