Pumping station
equipment

Pump NDR2M

Description

The main parametric range of pumps NDR-2M with an electric motor power of 0.25 kW:

Diaphragm dosing pumps have been developed as a replacement for conventional piston pumps used in technological processes in which leaks of the pumped medium are unacceptable.

It is known that the piston seal of conventional pumps works reliably provided that it is constantly lubricated. Lubrication can be achieved in two ways:

A) supplying a special barrier fluid to the sealing area at a pressure exceeding the working pressure of the pump;

B) organization by sealing of a normalized (droplet) leakage of the pumped liquid.

Both methods are related to the complication of pump maintenance, the need for constant monitoring, tightening and replacement of seals. In addition, in the first case there is a leakage to the outside of the sealing-lubricating fluid, in the second - pumped.

A characteristic feature and the main advantage of diaphragm pumps is the complete tightness of the pumped liquid in relation to the environment. The seal in such a pump does not require maintenance during operation.

Diaphragm dosing pumps of the NDR2M type made for pumping liquids and suspensions, including toxic and aggressive ones. The pumps have a modular design. Main components: drive, clutch, electric motor, hydraulic part.

The drive is specially designed for use in a diaphragm pump, but can also be used with conventional piston hydraulics. The piston stroke adjustment system with which the actuator is equipped allows a continuous adjustment of the flow from zero to the nominal value. Adjustment is possible when the pump is stopped and while driving.

The hydraulic part is an independent module. It consists of a reservoir for hydraulic (working) fluid, a diaphragm actuator cover, a piston seal, the diaphragm assembly itself and a valve box. The plug seal is maintenance-free. The membrane assembly is a two-layer membrane made of specially modified PTFE and a device for returning the membrane to its original position. Diaphragm, hydraulically loaded with mechanical preload. The device for returning the diaphragm to its original position by creating a preload significantly increases the suction capacity of the pump: it is possible to operate the pump at a pressure on the suction nozzle close to the vapor pressure of the pumped liquid. Rigid centering of the membrane ensures precise centering and thus a long service life. The two-layer construction of the diaphragm allows, in the event of a rupture of one of the layers, to continue the safe operation of the pump without changing its parameters for a certain time necessary to prepare for stopping and replacement of the damaged part. The possibility of signaling in case of damage of one of the membrane layers is provided. The hydraulic part is equipped with a built-in safety valve. The purpose is to protect the pump from overload in the event of an unacceptably large increase in pressure in the pressure line until it is completely shut down.

The modular design of the hydraulic part allows the modernization of dosing pumps in operation to obtain a new quality - tightness. Spare parts pumps from several manufacturers can be upgraded. The modernization consists in replacing the classic hydraulic part of the piston with a diaphragm part using an old drive and enables significant savings.