internal gear pumps has an external gear that is generally used to drive the
internal gear. The internal gear , which is smaller than the external gear
rotates on a pin and operates inside the external gear. The gear creates
voids as they come out of the mesh and liquid flows into the pump. As the
gears come back into mesh, volumes are reduced and liquid is forced out the
discharge port. Liquid can enter the expanding cavities through the external
teeth or recessed areas ion the head, alongside the teeth. The pump head
prevents liquids from flowing to the suction port from the discharge port.
The external gear is driven by a shaft supported by bearings. The internal
Gear contains a bearing rotating on a stationary pin in the pumped liquid.
Depending on shaft sealing arrangements, the external shaft support bearings
may run in pumped liquid. This is an important consideration when handling
an abrasive liquid and can wear out a support bearing.
The speed of the internal gear pumps is considered relatively slow compared
to centrifugal types. Speeds up to 1,150 rpm are considered common. Because
of their ability to operate at low speeds, internal gear pumps are well
suited for high viscosity applications and where suction conditions
call for a pump with minimal inlet pressure requirements.
For each revolution of internal gear pumps, the gears have a fairly long
time to come out of mesh allowing the spaces between gear teeth to
completely fill and not cavitate. Internal gear pumps have successfully
pumped liquids with high viscosity and very low viscosity.
The internal gear pumps is non-pulsing, self-priming, and can run dry for
short periods. They're also bi-rotational, meaning that the same pump
can be used to load and unload vessels. Because internal gear pumps
have only two moving parts, they are reliable, simple to operate, and easy
to maintain. The External Gear is of Mild Steel and the Internal Gear is of
PB10 Material, which makes this pump fireproof. The industrial gear pumps
are available in Mild Steel and Stainless Steel.
HOW INTERNAL GEAR PUMPS WORK :-
Liquid enters the suction port between the rotor (large exterior gear) and
idler (small interior gear) teeth. The arrows indicate the direction of the
pump and liquid.
Liquid travels through the pump between the teeth of the "gear-within-a-gear"
principle. The crescent shape divides the liquid and acts as a seal between
the suction and discharge ports.
The pump head is now nearly flooded, just prior to forcing the liquid out of
the discharge port. Intermeshing gears of the idler and rotor form
locked pockets for the liquid which assures volume control.
4. Rotor and idler teeth mesh completely to form a seal equidistant from
the discharge and suction ports. This seal forces the liquid out of the
|ADVANTAGES : -
- Only two moving parts
- Only one stuffing box
- Non-pulsating discharge
- Excellent for high-viscosity liquids
- Constant and even discharge regardless of pressure conditions
- Operates well in either direction
- Can be made to operate with one direction of flow with either
- Single adjustable end clearance
- Easy to maintain
- Flexible design offers application customization
||APPLICATIONS : -
- All varieties of Fuel Oil & Lube Oil
- Resins And Polymers
- Inks and Pigments
- Castor Oil