NSh brand high-pressure oil pumps and their application

Gear pumps for hydraulic power stations

Hydraulic power plants operate on gear pumps. These pumps have a number of advantages. Thanks to the operation of two gears, from which they get their name, the pumps capture liquid and send it to the walls of their housing, after which it moves towards the discharge. The clutch of the gears is so tight that it eliminates the movement of fluid in the opposite direction.

Gear pumps have a long service life and high efficiency. At the same time, they are small in size and easy to install. Such pumps do not have working parts that could be affected by centrifugal force. Thanks to this, the pumps can operate at high speeds and create high pressures so that the hydraulic station can carry out more work. If necessary, they can change the direction of work. Also, these pumps work with flammable substances or viscous liquids, which makes them indispensable in the production of hydraulic power stations.

NSh gear hydraulic pumps for oil

Pumped liquid:

Kinematic viscosity of the pumped oil is 0.15·10-4 m2/s to 0.75·10-4 m2/s (2.3°ВУ…10°ВУ), temperature up to 353К (80°С).

Symbol

For example NSh 10-M-3 L U1 TU3632-014-05747979-97 , where:

• NSh - gear pump;
• 10 — working volume, cm3;
• M - modification;
• 3 — pressure version [pressure 16 MPa (160 kgf/cm2)];
• L - direction of rotation of the drive rotor, left, when viewed from the drive side (right - not indicated);
• U1 - climatic version and placement category according to GOST 15150-69.

Purpose

NSh type gear pumps are designed for pumping mineral oil into the hydraulic systems of tractors, loaders, agricultural, utility, road construction and tractors, machines and other equipment coupled with engines.

The pumps are produced in climatic version U placement category I according to GOST 15150-69.

Summary table of technical characteristics of centrifugal pumps of NSh types.

Design

NSh type pumps are mounted on a power take-off shaft; torque is transmitted using a splined connection between the pump shaft and the power take-off shaft.

The gear pump consists of a housing, a drive rotor, a driven rotor, support bushings, rubber cuffs, O-rings, front and rear covers and bolts with spring washers.

There is a hole in the front cover for the drive shaft to exit. From the outside, a cuff is pressed into this hole to seal the pump drive rotor.

The drive rotor of the pump has an extended splined shaft end. The pump is mounted on the power take-off shaft, torque is transmitted using a splined connection between the pump shaft and the power take-off shaft.

The principle of operation of a gear pump is as follows: when the driving and driven rotors rotate, a vacuum is created on the input side, as a result of which liquid under atmospheric pressure fills the cavities between the teeth and moves into them from the input side to the output side. At the outlet, when the teeth engage, fluid is squeezed out into the system.

Application

• Mechanical engineering - for pumping mineral oil into hydraulic systems (various mechanisms, tractors, loaders, agricultural machines, road construction equipment)

Features/Benefits

• the simplicity of the design ensures its high reliability. High efficiency is achieved through the use of hydraulic pressure to adapt gaps
• pumps require virtually no maintenance
• Compact dimensions of the pumps allow them to be used in limited spaces
• pumps use single mechanical seals of various types and materials (no need to organize a barrier fluid supply)
• Pumps NSh10M, NSh32-M are commercially produced - at customer's request, pumps are produced with both right and left rotation directions

Pump options for hydraulic power stations (oil stations).

Pumps of the “K” series are suitable for most hydraulic power stations (oil stations). These gear pumps have an equally strong through-body housing made of rolled aluminum. The aluminum alloy used to make these pumps and their bushings is made using high pressure die casting. It is highly durable and has high anti-friction characteristics. The minimum rotation speed of such pumps is 500 rpm.

Gear pumps are divided into several groups. The first group includes pumps with a working volume from 0.8 to 12 cubic meters. cm. Their nominal pressure is from 25 to 14 MPa. The maximum short-term pressure they can create is from 28 to 16 MPa, depending on the volume, the maximum peak pressure is from 30 to 20 MPa. The maximum rotation speed of the blades is 3600 or 4800 rpm, depending on the volume of the working cavity.

The second group includes pumps with a displacement from 4.5 to 32 cubic meters. see. The nominal pressure created by these pumps is also from 25 to 14 MPa. The maximum short-term pressure is from 16 to 28 MPa, and the peak pressure is from 30 to 20 MPa. This group differs in a large number of maximum rotation speed options. For these pumps it can be from 2400 to 4000 rpm.

Group 2.5 includes more powerful and larger pumps with a displacement from 16 to 45 cubic meters. cm. The nominal pressure for this group is from 25 to 22 MPa, the maximum short-term pressure is from 28 to 25, and the peak pressure is from 30 to 28. The maximum rotation speed will be 3600 or 3000 rpm.

Description

A gear (gear) pump is a special type of positive displacement rotary machine. This is a device in which the working body is presented in the form of two gears located in the housing. The operation of such pumps is very simple due to the simplicity of their design. They are reliable and durable in operation. And what is important, such units are small in size. Having the same principle of operation, their structure can differ significantly. Therefore, their use is widespread and relevant for many industries. Currently, there is a large selection of gear pumps on the market. Many of them can be found by clicking here.

Gear pumps "Gidrosila"

We offer pumps manufactured by Gidrosila. This is a company that has been manufacturing hydraulic components for decades. Products under the Hydrosila brand are successfully sold throughout Russia and beyond. We are a long-time partner and official distributor of the company and offer equipment at the best prices. We present all the pump options that Hydrosila offers. If you do not find a specific product in our catalog, please contact our managers.

We have a large selection of gear pumps for hydraulic power stations (oil stations). Our managers can familiarize you with the detailed characteristics of each pump. CJSC Stroimashservice delivers pumps and other equipment for oil stations through a developed dealer network and throughout Russia with the help of transport companies. We care about your convenience!

Pump classification

It is worth noting that this division is conditional and depends on the presence of any sign in a particular pump. Pumps are distinguished by: 1. Clutch (they can be internal or external); 2. Mechanism (have screw, chevron, straight teeth); 3. Type of rotation (right, reverse or left); 4. The number of interlocking rotors (two-rotor and multi-rotor); 5. Number of stages (single and multi-stage); 6. Available regulation (regulated or unregulated); 7. Pressure supply (unloaded, unloaded or with automatic adjustment of end clearances).

It is impossible to classify a pump based on one of its characteristics. It is necessary to rely on all available signs.

External gear pumps

Such devices are more common. The gears are not located one inside the other, but are located opposite each other, and their rotation occurs evenly in completely opposite directions. An electric motor drives the shaft with the drive gear. She starts to spin. And thanks to it, the driven gear begins its work.

In the working chamber, a minimum free space appears between the gear teeth; during rotation, a vacuum appears in the suction zone. In the place where the teeth of the gears engage each other, locked volumes appear. This leads to the formation of a large volume of resistance due to the low compressibility of the working fluid. This is one of the most pressing problems of pump manufacturers, which they have been trying to combat for many years.

Internal Gear Pumps

A special feature of such pumps is the presence of two gears, one of which is located inside the other. A distinctive feature of this type of pump is its compactness. If we talk about the location of the gears themselves and their teeth, then the outer gear has internal teeth, and the inner gear, on the contrary, has external teeth. The moment both gears begin to rotate, a vacuum is created in the suction cavity. Here the working fluid enters the free cavities between the teeth, and then into the injection cavity itself. Such a pump must have a check valve to prevent pump failure due to increased pressure when liquid exits into the discharge pipe. The working substance here forms a vicious circle. As soon as the pressure in the discharge pipe increases, the liquid moves to the valve. The valve is squeezed out by liquid, which immediately returns to where it originates (to the suction zone).

Such pumps are less common because they require more precise sizing of the pump device. But they are the most compact, since one gear is located inside the second gear.

Applicability and installation dimensions of NSh 32 pumps