JPS61279784A - Force-feeding method on free piston pump for slurry - Google Patents

Abstract

PURPOSE:To prevent any change in flow speed and pressure by making one of the free pistons of the cylinders start to move before the extrusion moving limit position of another free piston. CONSTITUTION:When it is detected by a limit switch LS-L that a piston 1 has come to the lower limit position, a valve A-SI is opened, and slurry is supplied through a slurry supply pipe 6. Next, when it is detected by a limit switch LS-H that the piston 1 has come to the upper limit position, a valve A-WI is opened, and clean water is supplied through a clean water supply pipe 9. The piston 1 descends, and slurry is forcibly fed by this mechanism. Then, it is detected by a limit switch LS-M that the piston 1 comes nearby the lower limit position, and a valve B-SO of the second cylinder B is opened. The same operation is, thereafter, repeated among respective cylinders A, B, C. Slurry is to be forcibly fed in succession by the above operation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for pumping slurry in a free piston pump.

Prior Art Slurry free piston pumps, which consist of multiple cylinders with internal free pistons, have been operated in a conventional manner. That is, the free piston of one of the plurality of cylinders is lowered to pump the slurry, and when the free piston reaches the lower limit position, the free piston of one of the other cylinders is lowered. Slurry was pumped continuously.

The problem that the invention aims to solve
1, 1, 4, 58. . Yoyo7. -, Yu, 2ka8□
[If you want to start the next descent of the free piston when it reaches the limit position, perform a valve masterpiece etc. during that time.
i′(′, so the next free piston descent is actually temporal.]
.

It was scheduled to start a little later. Shitakatsu
□・nθ, and conventionally, at the time of switching the pressure stroke, 1
11. ゛Problem that flow velocity fluctuation and pressure fluctuation occur
There was □′.

The present invention solves these problems and provides a slurry that can prevent flow rate fluctuations and pressure fluctuations.
Provides a pressure feeding method for free piston pumps for 1.
1'.
゛'Means for Solving the Problems In order to solve the above problems, the pressure feeding method in the free piston pump for slurry of the present invention is a free piston pump for slurry that is composed of a plurality of cylinders each having a free piston inside. When pumping slurry with
The free piston of one of the cylinders was moved to pump the slurry, and the movement of one of the other free pistons was started before the extrusion movement limit position of the free piston.

In other words, in this method, the pressure feeding strokes partially overlap, and the flow rate fluctuation and pressure fluctuation due to time lag, which is conventional, is prevented.

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows a free piston pump for slurry according to the present invention. In the figure, (A) (a (Q is the first to eighth vertical cylinders, (1), (2), and (3) are the free pistons disposed in each cylinder so that they can move up and down. , are set to move up and down with timings shifted by 1/8 cycle from each other.(4) is fitted into the groove on the outer peripheral surface of each free piston (1), (2), and (3), and the cylinder <A ) @ (The sealing material that comes into contact with the inner circumferential surface of Q, (5) is a slurry tank into which, for example, coal slurry is put. (6) has one end connected to the lower end of the slurry tank (5) and the other end. Each branch part (6a) of is connected to the cylinder) @ (slurry supply pipe connected to the lower part of Q, (7) is the slurry supply pipe (
6) is a slurry pump installed in the middle, (8) is a fresh water tank, and (9) is connected to the lower part of the fresh water tank (8) at one end, and each branch part (9a) at the other end is connected to a cylinder prisoner. (B) (Fresh water supply pipe connected to the upper end of Q, Q
o (B) (2) is a fresh water high-pressure pump flow meter and flow control valve installed in the middle of the fresh water supply pipe (9), (2) is a branch part (ljla) at one end connected to each cylinder) ( 6)(
Connected to the upper end of Q and the other end is a fresh water tank (8)
The fresh water discharge pipe 1J41 inserted inside is a slurry transport pipe in which each branch part (i4a) at one end is connected to the lower end of each cylinder (Ill (C)) and the other end is extended to a specified location It is.

(A-5I) (B-5l) (C-5I) is a knob inserted in each branch part (6a) of the slurry supply pipe (6);
(A-WI) (B-Wl) (C-WI) is the fresh water supply pipe (
9), a valve installed in each branch part (9a) of (A-5)
o) (B-5O) (C-SO) is the fresh water discharge pipe (to)
A valve installed in each branch part (1sa) of (A-5O
) (B-8o) (C-5o) are valves installed at each branch part (14a) of the slurry transport pipe α. (LS-
H) is a limit switch that detects the upper limit position of the piston of each cylinder (4) (B3 (Q), (LS-L) is a limit switch that detects the lower limit position of the piston of each cylinder (A) (6) (Q, -M) is a position fl near the lower limit of the piston of each cylinder CB) (C) (intermediate position 1i!
i) are installed on the side wall of the cylinder (A) @(0) at the required positions. Note that (to) is the slurry return pipe connected in the middle of the slurry supply pipe (6), (SR) is a valve inserted in the middle.

Hereinafter, the operation of the above configuration will be explained based on FIG. 2. First, lower the piston in the first cylinder and check that it has reached the lower limit position by pressing the limit switch (LS-L).
), and in this case, if the piston (1) does not stop at the lower limit position but goes to the lowest limit position, stop the operation immediately (2). Next, the limit switch (
If the piston (1) is detected to have reached the lower limit position at LS-L), the valves (A-5O) (A-WI) will be closed/Now, after this, the valve (A-WO) will be opened. ).

Then, open the valve (A-8I) and supply slurry through the slurry supply pipe (6).

□ This causes the piston (1) to rise.
1st order 26, pyu): / (1) ka5 upper limit position 3. Rice. 89. If this occurs, the screw □ton (1) will not stop at the upper limit position but will go to the upper limit position (if something like this occurs, stop the operation immediately (turn the switch (LS-H)). ).Next, limit switch (LS-H)
So piston (1) is up:.

If it is detected that it has reached the limit position, the valve (A-51)
'□ (A-WO) closed), after this,
Valve (A-5O) □j□rc t 6 (
IJ). A, 2, i, 2 (A-WI) □. ,
1□1 yoyo m W (9) or 9, yo. 11 days. .

E From 1, the piston (υ) will descend and the slurry will be pumped II'.
The limit switch (LS-M) detects that 1) is near the lower limit position (l/L) and opens the valve (B-5o) of the second cylinder (B). Thereafter, the same operation is repeated between each cylinder (4) @ (C). This allows the slurry to be continuously pumped.

Cylinder prisoner @ (if 0 operation is not performed (4) (b)
Please open the valve (SR) @ to the slurry return pipe)
through which the slurry is circulated to the slurry tank (5).

FIG. 8 shows the pumping and supply of slurry, the movement of the piston, and the opening and closing states of the automatic opening and closing valve during automatic operation. That is, as is clear from the figure, the slurry pumping strokes of each cylinder (Q) partially overlap, which prevents flow rate fluctuations and pressure fluctuations due to time lags as in the prior art.

Effects of the Invention According to the present invention, it is possible to prevent flow rate fluctuations and pressure fluctuations that occur at the time of switching the slurry pumping stroke, and to perform stable slurry pumping.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, the first factor is a schematic diagram of the free piston pump for pumping slurry according to the present invention, FIG. 2 is a flowchart, and FIG. 8 is a diagram showing the pumping and supply of slurry during automatic operation. It is a diagram showing the movement of the piston and the opening/closing state of the automatic PD opening/closing valve.

Claims (1)

[Claims] 1. When pumping slurry with a free piston pump for slurry that is composed of multiple cylinders with free pistons inside, move the free piston of one of the cylinders to pump the slurry, and push out the free piston. A pressure feeding method in a free piston pump for slurry, characterized in that the movement of any other free piston is started before the movement limit position.