CONTROLLED VOLUME PLUNGER PUMPS AND PUMPING U

Usage

The controlled volume plunger pumps and pumping units of this type are designed for the pressure volume dosing of neutral and aggressive liquids,

emulsions, and suspensions with the kinematic viscosity of 8.5х10–7 m2/sec to 8х10–4 m2/sec (0.0085 St to 8 St) at a temperature of 258 К to 473 К (minus15 °C to plus 200 °C and above), the concentration of the solid nonabrasive phase of not more than 10% w/w, with the maximum density of particles of up to 2000 kg/m3, and with the size of a grain of the solid nonabrasive phase of not more than 1% of the internal diameter of the inlet pipe.

Design

The НД pumping unit consists of a drive and a pump. As the drive, an electric motor and a motor-reducer may be used.

The pump consists of a simplex or duplex moving mechanism and the corresponding number of hydraulic cylinders.

The moving mechanism includes a built-in worm-and-wheel gearbox, a crank mechanism to convert the rotary motion to the reciprocating motion, and a

plunger stroke control. The worm-and-wheel gearbox may be absent (in the case of pumps driven by the rocker of a conventional pumping unit).

The hydraulic cylinder consists of a cylinder body, a sealed plunger, ball-and-socket valves, and connecting pipes.

Designation

An example of designation of a pumping unit of ND type:

where

2 is the number of plungers (single-plunger pumps —no designation; 2 — double-plunger pumps);

НД is the make by the usage and design features (controlled volume pump with no heating (cooling) jacket —НД, controlled volume pump with a heating

jacket — НДО);

1.0 is the dosing accuracy category (0.5; 1.0; 2.5; no category);

Э is the delivery control method (manual with the pump stopped — no designation, manual on the run — Р,remote by means of an electric actuator — Э, the same using a frequency converter — Эч, the same using a pneumatic actuator — П);

800 is the delivery, (L/h);

63 is the outlet pressure of the pump, (kgf/cm2);

Д is the make by flow passage material (20Х13 steel —D, 12Х18Н10Т steel — К);

1 is the make by plunger seal type (chevron cups — 1, a sealing gland — 2);

4 is the make by plunger seal design (with feeding a liquid coolant, a hydraulic lock liquid, or a flushing fluid —4);

В is the make by the explosion-proof class of the motor (general industrial purpose motor — А; explosion-proof motor — В);

М1 is the modernization index (M1, М2 and so on);

УХЛ4 is the climatic version and arrangement category

(У2, У3, УХЛ4, Т2, Т3);

ТУ У 3.19-05785454-058-96 is the reference of the technical specification.

Based on the controlled volume pumps, the following plants are manufactured:

• Single-component volume dosing (УНД) plants for a dosed injection of corrosion inhibitors, wax and salt deposit inhibitors, demulsifiers, and other products into gas- and oil-field lines and facilities;

• Multi-component (up to 6 components) volume dosing (УМД) plants for a simultaneous injection of a dosed quantity of liquids or mixtures of liquids, emulsions, and suspensions at a temperature of 258 К to 373 К (minus15 °Сt o plus 100 °С) into a technological line.

Multi-plunger pumping units may supply liquids either by each cylinder separately or jointly in various combinations at both inlet and outlet.