GB2200387A - Twin-spout giant hydraulic pulser - Google Patents

Abstract

A two-spout hydraulic pulsating monitor comprises a housing (1) with seats (2, 3) forming spaces (4, 5, 6) inside the housing (1). Located in spaces (6) and (5) and forming chambers (11, 12, 13, 14) are pistons (10) and (9) interconnected by a rod (15), the cross-sectional area of piston (9) being K times larger than the cross-sectional area of the piston (10) where K ranges from 1.2 to 1.5. The chamber (11) communicates with the space (4) connected to the inlet pipe (24), the chambers (12, 13) are connected to the nozzle-carrying spouts (16, 17) and the chamber (14) is connected by the pipe (21) to the nozzle-carrying spout (17) and is vented to the atmosphere through a valve (23). <IMAGE>

Description

TWIN-SPOUT GIANT HYDRAULIC PULSER The invention relates to mining work involving the use of a liquid jet and more particularly, to two-spout hydraulic pulsating giants.

The invention will prove useful in mining industry and water-engineering works for breaking rocks with pulsating water jets without a pressure rise within a pulse, and in power engineering for cleaning heat-and-power-producing elements of boiler units in electric power stations.

Renown in the previous art is a two-spout hydraulic pulsating giant (Author's Certificate of the USSR No.962611, IPC E12C 25/60, 1982) comprising a housing closed at opposite ends with covers and having seats forming the first1 second and third spaces inside said housing, the first of these spaces being contained between the seats and the housing walls while the second and third spaces are limited by the housing walls, seats and housing cover, pistons arranged coaxially with the housing in the second and third spaces, respectively, forming the first, second, third and fourth chambers and interconnected by a rod capable of moving axiallg, first and second noszle-carrying spouts and first, second and third hinges, the first and second hinges being installed on the housing and connected with the second and third chambers and with the first and second nozzle-carrying spouts, respectively, the first and second pipes which connect the first and fourth chambers wit the first and second nozzle-carrying spouts, a pipe with a valve venting the first chamber to the atmosphere, an inlet pipe connected with the housing and communicating with the first space through the third hinge. Wne third hinge is mounted on the frame and has the form of a case and standpipe, the case containing an annular chamber and the standpipe having ports. The standpipe merges into the housing. The first and second hinges have chambers.Some of these chambers communicate with the nozzle-carrying spouns: and with the second and third chambers through ports while the others are connected through holes not only with the first and fourth chambers but, through the first and second pipes, with the first and second nozzlecarrying spouts, respectively. The hydraulic resistance of the pipes is considerably higher than that of the nozzles. The first and fourth chambers are separated from the air chambers by diaphragms whose travel is limited by limiting strips.

The operating principle of the giant is based on transforming the steady flow of water into pulsating flow dischargid alternately from the spounts without a pressure rise wittiin the pulse.

The covers in the known two-spout hydraulic pulsating giant are made in the form of air chambers and the crosssectional areas of the flow interrupter pistons are equal to each other. This results in a slow motion of the pistons from one extreme position to the other owing to a gradual change of pressure in the chambers formed by the pistons, air chambers and housing walls which reduces the frequency of liquid pressure pulses in the spouts and impairs the hydraulicking efficiency. besides, the provision of air chambers calls for a precise coordination of their parameters otherwise it may happen that during the slow motion of the pistons the pressures in the chambers formed by the pistons, air chambers and housing walls become equalized so that, the piston areas being equal, the forces acting on them also become equal.As a consequence, the flow interrupter will take an intermediate position and the liquid will issue from both nozzle-carrying spouts, i.e. the giant will run out of the solfexcited oscillations mode.

An object of the"invention resides in improving the efficiency of hydraulickigg.

Another object of the intention is to increase the speed of motion of the piston witn rod.

One of the objects of the invention lies in increasing the frequency of liquid pressure pulsations in the nozzle-carrying spouts.

The essence of the invention lies in that in the two-spout hydraulic pulsating giant comprising a housing closed at the opposite ends with covers and provided with seats forming three spaces inside the housing the first of these being contained between the seats and housing walls , each of the two other spaces being accommodated between one of the seats, housing walls and the corresponding housing cover, a rod, the first and second pistons installed, respectively, in the second and third spaces forming the first, second, third and fourth chambers and interconnected by the rod with a provision for axial movement, the first and second nozzle-carrying spouts connected with the housing and communicating with the second and third chambers, respectively, a pipe one end of which communicates with the first chamber vented to the atmosphere through a valve, while its other end communicates with the second nozzle-carrying spout, an inlet pipe connected with the housing and communicating with the first space, accord- ing to the invention, the fourth chamber communicates with the first space, the cross-sectional area of the piston in the second space being K times larger than the cross-sectional area of the piston in the third space where K ranges from 1.2 to 1.5 and the covers are of a rigid construction.

It is practicable that the fourth chamber be put in communication with the first space through an additional pipe.

This construction of the hereinproposed two-spout hydraulic pulsating giant provides for an increase in the frequency of the liquid pressure pulsations in the spouts thus enhancing the hydraulicking efficiency.

Now the invention will be described by way of example with reference to the accompanying drawing which shows a general view of the two-spout hydraulic pulsating giant, longitudinal section, according to the invention.

'Une two-spout hydraulic pulsating giant comprises a housing 1 with seats 2, 3 forming spaces 4, 5, 6 inside the housing 1, the space 4 being contained between the seats 2, 3 while spaces 5 and 6 are contained between the seats 3 hnd 2 and tne end covers 7, 8 of the housing 1, respectively, pistons 9, 10 installed in spaces 5, 6, respectively, and forming chambers 11, 12, 13, 14 and nozzle-carrying spouts 16, 17 interconnected by a rod 15 with a provision for axial movement, and hinges 18, 19, , 20. The hinges 18 and 19 are installed on the housing 1 and connected with chambers 12, 13 and with nozzle-carrying spouts 16 and 17, respectively. The covers 7, & are of a rigid construction.

'l'he two-spout hydraulic pulsating giant comprises pipes 21, 22, the pipe 21 being connected with the chamber 14 and nozzle-carrying spout 17 while the chamber 11 is connected with the space 4 in the given embodiment through the pipe 22. Other versions of communication between the chamber 11 and the space 4 are also possible, e.g.

through a passage in the housing 1, the pipe 23 with valve 23' communicating the chamber with the atmosphere, and the inlet pipe 24 connected through the hinge 20 with the space 4.

The cross-sectional area of the piston 9 in the space 5 is K times larger than the cross-sectional area of the piston 10 in the space 6, the value of K ranging from 1.2 to 1.5.

The hinge 20 is installed on the frame 25 and has the form of a case and a standpipe 27, the case 26 being provided with an annular chamber 28 and the standpipe 27, with ports 29. The standpipe 29 is connected with the housing 1.

The hinges 18 and 19 have chambers 30 , 31 communicating through ports 32 and 33 wit the nozzle-carrying spouts 16, 17, respectively. There is a hole 34 in the housing 1 between the chamber 14 and the pipe 23 with the valve 23'.

The two-spout hydraulic pulsating giant functions as follows.

When the valve 23' is open, the pistons 9 and 14 with the rod 15 occupy an extreme position in which the access of water to the nozzle-carrying spout 16 is denied at the same time opening the access of water to the nozzle-carrying spout 17. This is attributable to the force acting on the piston 10 from the side of the chamber 11 which communicates through pipe 22 with the space 4 of the housing 1 of the two-spout hydraulic pulsating giant. water delivered from the inlet pipe 24 passes through the annular chamber 2d, the case 26 of the hinge 20, through the ports 29 of the standpipe 27 and the standpipe proper, fills the space 4 of the housing 1, passes through the gap between the seat 3 and piston 9, enters the chamber 13, ports 33, chamber 31 of the hinge 19, nozzle-carrying spout 17 and escapes through the nozzle into the atmosphere onto the object of destruction. Besides, water flowing from the spout 17 and passing through the pipe 21 fills the chamber 14 and is discharged into the atmosphere through the hole 34 and valve 23'. Pressure in tis chamber 14 is close to the atmospheric pressure.At the same time water flows through the pipe 22 into tne chamber 11 from the space 4 and is subjected to the pressure delivered to the two-spout hydraulic pulsating giant so that this chamber is under a constant pressure equal to the liquid pressure. The hydraulic pulsating giant is put into the self-excited oscillations mode by closing the valve 23' (The valve is controlled from the control console, not shown in the Figure). Pressure in the chamber 14 after a certain period of time becomes equal to that in the nozzle-carrying spout 17.Inasmuch as the cross-sectional area of tne piston 9 is K times larger than the cross-sectional area of the piston 10, the force arising at the side of the piston 9 is K times larger than that at the side of the piston 10. tI'he resultant force moves the pistons 9 and 10 with the rod 15 to the extreme position in which the piston comes to bear against the seat 3. The flow of water to the nozzle-carrying spout 17 is shut off while its flow to the nozzle-carrying spout 16 opens up.

Thus water now rushes from the space 4 not into the spout 17 but into the spout 16, passing through the gap between the seat 2 and piston 10, through the chamber 12, ports 32, chamber 30 of the hinge 18, the nozzle-carrying spout 16 and issues from the nozzle of the spout 16 into the atmosphere onto the object of destruction. At the same time the water pressure in the nozzle-carrying spout 17 drops to the atmospheric level and the wave of this pressure moves through the pipe 21 into the chamber 14. At the moment when this wave comes to the chamber 14, the forces on the pistons 9 and 10 are redistributed due to the difference of areas of the pistons 9 and 10 and of pressures whose resultant moves the pistons 9 and 10 with the rod 15 from the seat 3 to the seat 2. Water stops entering the nozzlecarrying spout 16 and starts entering the nozzlecarrying spout 17.Thus, stepped changes of water pressure are ensured in the chamber 14. When the flow of sater to the spout 17 is shut off, the pressure in the chamber 14 settles at the atmospheric level. sihen water is admitted to the spout 17, pressure in the chamber 14 becomes equal to the pressure of the delivered water. The processes taking place in the nozzle-carrying spouts 16 and 17 alternate and continue in the manner described above. Hence, water issues from the nozzle-carrying spouts on the object of destruction alternately. The stationary flow of water is transformed into pulsating flow without the pressure rise within the pulse at a pulsation frequency of about 20 - 25 Hz.

huts, connection of the chamber 11 with the space 4 by a pipe 22, making the cross sectional area of the piston 9 K times larger than the cross sectional area of the piston 10 and the rigid construction of the covers.7, 8 ensure such a redistribution of forces on the pistons 9 and 10 with the rod 15 which increases the speed of motion of the pistons 9 and 10 with the rod 15 from 5.0 m/s to 6.0 m/s.

In the end this steps up the frequency of water pressure pulsations in the spouts 16, 17 from 10 - 12.5 Hz to 20 - 25 Hz. in addition, it should be borne in mind that the two-spout hydraulic pulsating giant is a sophisticated dynamic system whose links are described by difLerential equations of the 2nd order in the partial derivatives (spouts, pipes, inlet pipe) and by differential equations of the 2nd order (equalization of piston motion with the rod), therefore the K factor is found experimentally and varies from 1.2 to 1.5. If K is smaller than 1.2 times, the two-spout hydraulic pulsating giant does not enter the mode of self-excited oscillations. Water is discharged from the nozzle-carrying spout 17. Closing the valve 23' fails to exert any influence on the giant and water flows in a stationary way from the nozzle-carrying spout 17.

This should be attributed -to the fact that the force from the side of the piston 9 is smaller than that from the side of the piston 10. Therefore, the piston 10 will cc.lstantly dwell at the seat 2. In the case when K is set within the limits from 1.a to 1.5 times, the twospout hydraulic pulsating giant enters easily the mode of self-excited oscillations, is controlled by the valve 23' and ensures the frequency of pulsations of 20-25 Hz of the water pressure in the spouts 16 and 17 which is twice as high as that of the prototype. If K is larger than 1.5 times, the giant fails to enter the mode of self-excited oscillations and its pistons 9 and 10 with rod 15 occupy a middle position when the valve 23' is closed, which means that water flows out of botn spouts 16 and 17 into the atmosphere since the forces at the sides of the pistons 9 and 10 in this case are counterbalanced.

Tne invention increases the efficiency of rock breaking by raising twice the frequency of water pressure pulsations within the pulse.

i0he concrete embodiment of the invention is illustrated by the drawing showing a general view of the two-spout hydraulic pulsating giant, longitudinal section, according to the invention.

Claims (3)

1. 'lio-spout hydraulic pulsating giant comprising a housing closed at opposite ends with rigid covers, having the first and second seats forming three spaces inside the housing, the first of which is contained between the seats and walls of the housing while each of the other two spaces is contained between one of the seats, corresponding cover and housing walls, a rod, the first and the second pistons installed coaxially with the housing in the second and third spaces, forming the first, second, third and fourth chambers and interconnected by a rod with a provision for axial movement, the fourth chamber being connected with the first space and the cross sectional area of the pistor installed in the second space being E times larger than the cross sectional area of the piston installed in the third space where A varies from 1.2 to 1.5, the first anus second nozzle-carrying spouts, connected with the housing and communicating, respectively, with the second and third chambers, a pipe one end of which communicates with the first chamber which is vented to the atmosphere through a valve, while its otner end communicates with the first nozzle-carrying spout , an inlet pipe connected to the housing and communicating with the first space.

2. Two-spout hydraulic pulsating giant as claimed in Claim 1 comprosing an additional pipe through which the fourth chamber communicates with the first space.

3. Two-spout hydraulic pulsating giant realized essentially as disclosed in the description with reference to the accompanying drawing.