Critical areas in any submersible motor pump design are unquestionably its Winding, Sealing and Bearings. These three parts are like a heart for any submersible pumps & are very much interdependent on each other. So it is utmost important that the Special attention is given to these aspects while designing a submersible pump set. Generally any Slight water / moisture seepage inside the motor means winding failures. This will occur within a short time, if seal fittings are not perfect or do not remain perfect, during use. Preventing of water seepage inside the motor is a constant worry of the Designer. The skill lies in preventing it, by using the best available material, method and the proper workmanship. The available epoxy for winding, moisture sensing devices are some of the methods many Designer use to protect the motor, but, it is like applying cement to wooden walls or paint to corroded metal surfaces. The important question here is weather these are the only available options?
Darling Engineers don't think so!
We don't keep our motors empty or so called “Air filled” under water. We fill them with oil even at the cost of inserting extra iron and copper for the pump motor. The use of the oil filled concept for DARLING motors together with PVC Insulated wire not only gives tremendous advantage in terms of quality but also has loads of beneficial side effects like the ones mentioned here.
It gives us pleasure to discuss important facts & advantages for DARLING PUMPS :
Oil Filled Motors
PVC insulated Winding
Oil filled motor automatically helps Darling pump seals and bearing last longer and due to constant lubrication keep them cool as compared to other submersible pumps, where lubrication is to be given by the maintenance crew every now & then.
Mechanical seal being a trouble prone and an expensive item, every user naturally wishes to play safe. Darling pump not only use the better seals, but the design is such that the importance of mechanical seal is negated to certain extent & makes sure that even if seal fails, the motor winding (since 100% water proof PVC Insulted winding wires are used) is not harmed, as compared to other makes, wherein the pump gets completely burnt but out and it has to be rewound. It is a universally acknowledged fact that liquid never flows from low pressure zone to High pressure zone Darling pumps have successfully adopted this principle wherein, when the motor operates, a high pressure zone is automatically created, due to the oil inside and the water outside cannot enter inside the motor thus making it further safe and complementary to the mechanical seal.
PVC insulated winding
Darling pumps are wound with Special PVC coated (WATER PROOF) Submersible Winding wire instead of Copper Enamelled winding wires which are NOT WATER PROOF.
Better heat transfer
Oil filled motor designs ensures better heat transfer & helps pump run cooler even when operated continuously, thereby offering long and reliable service in return.
Darling pumps DO NOT REQUIRE ANY OIL REPLACEMENT since it never gets heated up beyond its limits. Darling pump are generally designed for 360 volts to 440 volts Electric supply, which to certain extent negates the damage caused due to voltage fluctuation. Extra heavy duty Bearings does not require frequent maintenance. Our Oil filled design ensures proper lubrication to bearings even in case of continuous duty. As Darling Pumps are wound with PVC Insulated winding wire, in case of emergency the motor can easily rewound at site itself. You don't have to send it factory for repairs.