Internal Gear Pump in Dubai UAE
These pumps are mostly used for lubrication and feeding at pressures less than 1000 psi, but in multi-stage types, access to a pressure range of about 4000 psi is also possible. Abrasion efficiency reduction in internal gear pumps is greater than external gear pumps. These types of pumps require little inlet speed and pressure. Internal gear pump is one of the most widely used products sold in Marine land company in Dubai and Sharjah.
What is an internal gear pump?
A gear pump is a type of positive displacement pump (PD). Gear pumps use the function of gears to transfer liquids. The rotating gears create a liquid seal with the pump housing and create a suction at the pump inlet. The fluid that is drawn into the pump is trapped inside the teeth of the rotating gears and transferred to the drain. A gear pump offers a smooth, pulse-free flow commensurate with the speed at which its gears rotate.
There are two main designs of gear pumps: external and internal. An external gear pump consists of two identical and interconnected gears supported by separate shafts. An internal gear pump operates on the same principle, but two interconnected gears have different sizes, and one rotates inside the other. The larger gear (rotor) is an internal gear, ie it has protruding teeth inside. Inside this is a smaller external gear (idle gear - only the rotor moves) off-center. It is designed to be connected to the rotor so that the gear teeth engage at one point. A pinion and bush attached to the pump housing keep the idler in position. A fixed crescent-shaped partition fills the space created by the idler eccentric installation position and acts as a seal between the input and output ports.
Three stages of internal gear pump
The internal gear pump consists of 3 stages for its pumping action:
Filling, transfer, and delivery.
- As the gears come out of the mesh on the pump inlet side, they create an expanded volume. Fluid flows into the cavities and is trapped by the gear teeth as the gears continue to rotate against the pump cover and partition.
- The trapped fluid is transferred from the inlet to the discharge around the chamber.
- As the teeth of the gears lock together on the discharge side of the pump, its volume decreases, and the fluid is released under pressure.
The close tolerances between the gears and the chamber allow the pump to create suction at the inlet and prevent liquid leakage from the discharge side (although leakage is lower in low viscosity liquids).
Advantages:
1. It has a uniform output without oscillation.
2. It is very suitable for fluid with high viscosity.
3. Excellent performance of internal gear pump in both directions.
4. Requires a little NPSH *.
5. Internal gear pump is easy to maintain.
6. It has a flexible design according to the customer's needs.
7. It has suction itself.
8. Can work dry for a short time.
Disadvantages:
1. Internal gear pump has medium pressure limit.
2. Usually requires management on rotational speed.
3. Creates a lot of load on the shaft.
4. Internal gear pump does not have high operating speed.
Main applications of these pumps
Some typical applications of internal gear pumps are:
- Fuel oil and lube oil
- Resins and polymer
- Alcohols and solvents
- Asphalt, bitumen, and tar
- Polyurethane foam (Isocyanate and polyol)
- Food products such as corn syrup, chocolate, and peanut butter
- Paint, inks, and pigment
- Soaps and surfactants
- Glycol
Internal gear pump limitations:
- Internal gear pumps operate automatically. The gears in this type of pump must be lubricated so that they can be used for a long time. Keep in mind that these models of pumps need lubrication for their operation and if they are dry, they will not work properly.
- The close tolerances between the gears and the body mean that these pumps are prone to wear, especially when used with abrasive fluids or fed with bubbly solids. For these applications, internal gear pumps are more powerful and operate only one bearing (sometimes two bearings) in the fluid. A gear pump must always have a filter installed on the suction side to protect large and potentially harmful solids.
- It is recommended to use a high-capacity pump to remove abrasive solids. Because the speed of this type of pump is lower as a result it creates less wear. Note that gear pumps should not operate at a different speed than their ideal condition.
- When using this pump for high temperatures, first check that it is compatible with the pump temperature range. Because if the temperature is higher than the allowable limit of the pump, it causes the expansion of its components and ultimately reduces the space inside the pump. As a result, the wear increases, and if the intensity increases, it damages the pump.
- No matter how hard you try to maintain these pumps, the internal coating of these pumps will eventually wear out over time. Damage caused by the use of these pumps causes the pumped liquid to leak from the drain to the suction. In practice, wear has little effect until it reaches a critical point, from where performance decreases rapidly.