SU1312244A1 - Piston pump - Google Patents

Abstract

BACKGROUND OF THE INVENTION used for pumping fluids. The circuit of the invention is an increase in the efficiency of reducing the pulsation of the feed and the pressure on the liquid. Pneumatic compensators 4 are placed oppositely in the opposite blind end walls 5 of the collector 2. The area of the passage of the collector 2 is made according to a certain ratio that ensures the condition of the minimum amplitude of pressure at the pump outlet. 2 Il. yu yu

Description

The invention relates to pump construction, concerns nopuiiiCBbix pumps, and can be used to transfer current media in various sectors of the national economy.

The aim of the invention is to increase the efficiency of reducing the pulsation of the feed and the pressure of the injected fluid.

Figure 1 shows the pump, a longitudinal section; FIG. 2 is a section A-A in FIG. one .

The pump contains cylinders 1 interconnected by a discharge manifold 2 with discharge valves 3. At the ends of the manifold 2, pneumatic compensators 4 are installed. The latter are located opposite in opposed deaf end walls 5 of the collector 2, and the collector 2 passage area is made according to the following relationship:

f -F

(y + liYp

, 8V (

(one)

where f j

harmful

the area of the passage of the collector pa 2;

relative volume of cylinder 1;

VP is the working volume of cylinder 1;

V is the volume of the plate of the discharge valve 3;

F is the cross-sectional area of the injection valve 3;

F | - piston section area 6.

The pistons 6 are located in the cylinders and are connected to the drive by means of the rods 7. The cylinders are also provided with suction valves 8.

When the pump is operated, the pistons 6 move with a phase shift in the cylinders 1 at speeds varying sinusoidally. In the process of moving the pistons 6 in the 1C1 cylinder 1, the pumped medium is periodically sucked into the shchindry 1 through the suction valves 8 and is injected into the collector 2 through the discharge valves 3. I

Due to the variable speed of movement of the lorshny 6 in the collector 2, supply pulsations occur and, as a result, pressure pulsations, which, without taking into account the compressibility of the fluid, are determined by the formula

ililiUiJl. EQ

 f

dt

(2)

lp is the amplitude of the pressure pulsation; 1 - distance from the exit extreme,

first cylinder to the nearest pneumatic compensator 4; 1 - distance between pneumatic compensators 4;

dQ dt

the rate of change of the supply of the pumping medium as a result of a change in the speed of movement of the pistons 6; p - density pumped

environment.

Formula (2) shows that the efficiency of damping of pulsation increases with increasing area of the passage of the collector. 1% 1 The minimum value of the collector 2 passage area, the above of which further increasing the collector 2 passage area practically does not lead to a further decrease in pulsation, can be determined from the analysis of wave processes occurring in opposite collector 2 pneumocompensators 4 and characterized by ratios

„Sc / 04 Pr, .. W sincf ,, ()

ace

1 (ti, + tk,) E Gots tts + Shk. /. H

P .. w, s., F- -; ---; for v ,,

RS, W

sincf

(shopping center + 0,5t |,) B,

V. + VK

at

m rti c O and 5m c;

v7 ro75VK

V ,,

45)

where p

0

ace

W.

five

Ioh

m,

0

pressure amplitude in the outermost cylinders 1; pressure amplitude in the middle cylinder 1; maximum speed of movement of the pistons 6; the delay angle of the opening of the discharge valves 3;

reduced to the piston area the mass of translationally moving elements in cylinder 1; the cross-sectional area of the discharge valve 3; radius of the drive crank (not shown);

the bulk modulus of the working fluid; total volume of the pumped medium in cylinders 1;

3 1312244

 - the volume of the pumped medium in the manifold 2 between the uppermost cylinders and the nearest pneumatic compensators 4; with

 - mass of the pumped medium in the specified volume of the collector 2;

 - the total internal volume of the collector 2, filled with pumped medium;

, is the mass of the pumped medium in volume V.

those cl ow hl

From the condition of the minimum pressure amplitude on the BEiixoAe pump, taking into account expressions (2) - (5), determine the condition for choosing the passage area of collector 2, which is characterized by relation (1).

Claims (1)

Invention Formula A piston pump containing cylinders interconnected by an injection manifold with pressure valves, at the ends of which pneumatic compensators are installed, characterized in that, in order to increase the efficiency of reducing the supply pulsation and the pressure of the injected fluid, the pneumatic compensators are located opposite to opposite in the opposite blind end walls of the collector , moreover, the area of the passage of the collector is made in accordance with the following ratio ff f iF  llillyp Vp + 7,8V (Fn / Fj where f is the collector passage area; VP V FX F -relative harmful cylinder volume; - working volume of the cylinder; -volume discharge valve plates; - cross-sectional area of the discharge valve; - cross section of the cross section, Editor L. Langazo Compiled by V.Gruzrtsyuv Tehred A. Kravchuk Order 1947/31 Circulation 575 Subscription VNNPI State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab. - d. 4/5 Production and printing company, Uzhgorod, st. Project, 4 FIG. 2 Corrector S.Cherni