1. WQB explosion-proof submersible sewage pump

Compliant with GB3836.1-2010 “Explosive Atmospheres Part 1: General Requirements for Equipment” and GB3836.2-2010 “Explosive Atmospheres Part 2: Standard Requirements for Equipment Protected by Explosion proof Enclosures”, explosion-proof mark: ExdIBT4Gb, maximum surface temperature of electric pump not exceeding 135 ° C

2. Highly reliable explosion-proof submersible motor

Specially designed and manufactured explosion-proof submersible motor, the shell is made of HT250 material and has undergone static water pressure test. The machining accuracy, roughness, and positional tolerance of the explosion-proof surface have been strictly inspected. All explosion-proof surfaces are coated with 204-1 replacement type rust proof oil, and the inner cavity of the junction box is coated with 1332 arc resistant paint. The protection level of the electric pump is IP68, and the stator winding is F-class insulation. Due to the overall submersible operation of the electric pump, the cooling effect is good, and the temperature rise of the winding is low, making the motor operation more reliable

The cable is a sewage resistant heavy-duty rubber sheathed flexible cable, and the core section of the cable is selected for continuous full load operation at an ambient temperature of 40 ℃, which is very reliable. The cable is fixed twice on the handle to avoid damage during transportation, installation, and use.

3. Selected pump body and impeller

Using CAD technology for repeated design modifications to achieve the best match between the pump body and impeller, making it easy for fibers and debris to pass through without entanglement or blockage. The impeller is strictly balanced to reduce pump vibration and ensure smooth operation,

4. The motor has a tight seal and strict inspection

1) Sealing of the shaft

Two independent single end mechanical seals are arranged on the pump side and motor side respectively, forming two shaft seals, with a leakage rate of less than one tenth of that of the double end mechanical seal. The lubricating oil in the oil chamber lubricates and cools the friction pair of the motor side mechanical seal, and the pump side mechanical seal in contact with the medium adopts a hard to hard friction pair made of silicon carbide/silicon carbide, which has high hardness and low friction coefficient and is not prone to wear and failure; The mechanical seal on the motor side, which is immersed in oil as a whole, adopts a graphite/silicon carbide “soft to hard” friction pair, with a low friction coefficient and easy “running in”, ensuring reliable sealing. The small gap between the impeller and pump cover can prevent impurities from entering the shaft seal chamber while maintaining good working conditions of the mechanical seal. The rubber component of the mechanical seal is made of nitrile rubber with excellent oil resistance, while the spring and other structural components are made of stainless steel material

2) Sealing of cables

Tighten the screw cover and cable sealing ring to achieve reliable sealing between the cable and the wiring chamber.

3) Sealing between parts

O-shaped sealing rings are used as reliable static seals at the connection and fitting points between various parts

4) Sealing inspection

Only after passing the pressure test can the parts be assembled. Each pump undergoes strict air pressure testing during and after assembly to ensure the sealing of the motor

4. Reliable bearing configuration

We use high-quality deep groove ball bearings and double row angular contact bearings from well-known brands, which have sufficient load margin to ensure the reliable operation of the product.

5. Protective devices

The motor winding is equipped with an overheat protection element. When the winding temperature exceeds the specified temperature, the overheat protection element will turn on the “overheat” indicator light through the electrical control cabinet and automatically stop the machine. Remind operators to conduct inspections and identify the cause of motor overheating. After the winding temperature drops, the overheat protection element will automatically reset, and the motor will return to a bootable state. However, it should not be started until the fault causing the winding overheating is eliminated

Install a water leakage probe in the motor chamber for power of 3kW and above. When the mechanical seal on the motor side fails, oil or water in the oil chamber enters the motor cavity through the bearing chamber. The leakage probe installed in the motor cavity sends an alarm signal (the leakage indicator light is on) through the electrical control cabinet and automatically stops the pump, reminding the operator to inspect and repair the pump.

List of motor protection components installed inside the pump: