Speaking of a monobloc pump, it means the standard model of this equipment. The only difference is that the body of the centrifugal device, as well as the electric motor, are combined into one unit.
General arrangement of the unit
The liquid enters this device in the axial direction, but leaves it already in the radial direction. In order to reduce friction efficiency losses, the following design is used. The impeller from the centrifugal device is mounted directly on the motor shaft. Due to this, the friction that went to the connection with the bearings is reduced. In addition, this assembly method saves additional space. In order to create cooling of a monoblock pump, a rotating impeller is used, which is also located at the end of the motor shaft, on the opposite side of the wheel. The type of cooling used in this unit is air. The impeller is also additionally protected by a grille.
Pros,cons and scope
The characteristic of monoblock pumps allowed this device to find quite a wide application in many areas. The fact that the device has a universal design also contributed to the rapid and confident distribution. A pump is used to circulate fluid in the heating, cooling, hot water supply system. Used in booster pumping stations, to extinguish fires.
If we talk about the positive qualities of this device, then it has quite a lot of them. The first and most important quality is the wide range of operating parameters. The second important quality is the design, which is very compact. With their low cost, monoblock pumps have a significant efficiency factor - from 30 to 80%. In addition, the device is considered unpretentious to the quality of the incoming liquid. The temperature index of the liquid can exceed the mark of 100 degrees Celsius.
However, there are a number of some disadvantages:
- the design uses rolling bearings, as well as shaft end seals;
- the level of noise and vibration created by this device is much higher than, say, wet rotor units;
- installation of this fixture can only be done in one position so that the axis of the shaft is horizontal;
- installation of a monobloc pump is allowed either on the foundation or on the frame;
- demanding maintenance, due to the presence of stuffing boxesshaft seals.
Use the unit
The liquid moves through the suction pipe, in the axial direction. Having passed the pipe, the water enters the working zone of the wheel, which is supplied with several curved blades. Due to the action of inertial forces, the direction of movement changes - from the center of the wheel to its periphery. Fluid that swirls in the direction of its movement accumulates in an element such as a volute casing, from which it exits the pump. This part is called a "snail", and its main purpose is to drain the incoming fluid from the impeller, as well as to carry out the process of converting the dynamic pressure created by the movement of water into static pressure. The shape of the spiral housing is very similar to the diffuser element.
In a centrifugal monobloc pump, this sequence is observed. If there is a twofold increase in the speed of rotation of the wheel, then the feed will also double, the force of pressure will increase four times, but the consumed electricity will increase eight times.
Console implement type
The main purpose of this equipment is to pump liquid by rotating one or more wheels. It is also important to note that all devices are designed for different purposes. The main difference between them lies in the design, which determines the further operation of the device.
Currently, there are two most common types of monobloc pump belonging tocentrifugal type in its design.
The first place is occupied by a group of equipment, which is represented by single-stage pumps with a horizontal shaft arrangement, as well as a one-way inlet for such an element as the impeller.
In second place are centrifugal monoblock cantilever pumps. These units are marked with the letter "K", and are also driven by an electric motor. The main task of the device is to pump clean water in the system.
Usage and benefits of "K" pump
These units are used for pumping purified liquid for industrial or technical purposes. This is the main branch of their use. However, they are also used for some other purposes:
- providing water circulation in the heating and water supply system, as well as in household and residential buildings;
- used in industrial water supply systems;
- used to ensure the supply of water to holiday villages;
- used for firefighting in residential buildings.
Among the positive qualities of this equipment are several of the following parameters. The design of the unit is designed so that the body has its own supports. This will allow you to remove the device without disconnecting it from the pipeline system. The diameter of an element such as an impeller can be any. It is made according tothe wish of the customer. There is the possibility of individual selection of characteristics, based on the place and purpose of using the device.
Model TYPE "KM"
The main difference between the cantilever-monoblock type and the conventional type is that the impeller is located on the shaft. The inclusion in the work of this part is carried out due to the efforts of the electric motor. If the model has a mechanical seal, then the temperature range for the working fluid is from 0 to +105 degrees Celsius. If the seal is gland type, then the range is reduced to 0-80 degrees Celsius. If we talk about the maximum allowable pressure at the inlet to the pump, then in the presence of a mechanical seal, this is 6 atmospheres. When using a stuffing box seal, this is 3.5 atmospheres. It is also important to note that during the operation of the KM pump model, a slight content of mechanical impurities in the working fluid is allowed.
Monoblock circulation pumps
This type of equipment belongs to the category of low pressure device. The design of this device uses a conventional model of an electric motor with air-type cooling, as well as a constant speed. As in other models, the electric motor, as well as the working part of the device, are made in one block, and therefore belong to the group of monoblock equipment. The design is very easy to maintain and repair.
GRUNDFOS monoblock pumps
This company is engaged in the production and supply of models such as console-monoblock and console devices.
Serial number monoblock and console-monoblock models NB. The main characteristic of these units is 2900 rpm. Structurally, these devices are made of single-stage centrifugal with pressure nozzles, axial suction and radial types. The main purpose of these models is to increase pressure, as well as pumping fluid through systems such as district heating or heating equipment.
