GB2038902A - Machine for Cleaning Reclamation Channels from Deposits - Google Patents
Machine for Cleaning Reclamation Channels from Deposits Download PDFInfo
- Publication number
- GB2038902A GB2038902A GB7900232A GB7900232A GB2038902A GB 2038902 A GB2038902 A GB 2038902A GB 7900232 A GB7900232 A GB 7900232A GB 7900232 A GB7900232 A GB 7900232A GB 2038902 A GB2038902 A GB 2038902A
- Authority
- GB
- United Kingdom
- Prior art keywords
- nozzle
- deposits
- machine
- movable portion
- channel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
- E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
- E02F3/92—Digging elements, e.g. suction heads
- E02F3/9206—Digging devices using blowing effect only, like jets or propellers
-
- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01H—STREET CLEANING; CLEANING OF PERMANENT WAYS; CLEANING BEACHES; DISPERSING OR PREVENTING FOG IN GENERAL CLEANING STREET OR RAILWAY FURNITURE OR TUNNEL WALLS
- E01H1/00—Removing undesirable matter from roads or like surfaces, with or without moistening of the surface
- E01H1/08—Pneumatically dislodging or taking-up undesirable matter or small objects; Drying by heat only or by streams of gas; Cleaning by projecting abrasive particles
- E01H1/0809—Loosening or dislodging by blowing ; Drying by means of gas streams
- E01H1/0818—Loosening or dislodging by blowing ; Drying by means of gas streams in apparatus with mechanical loosening or feeding instruments, e.g. brushes, scrapers
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02B—HYDRAULIC ENGINEERING
- E02B3/00—Engineering works in connection with control or use of streams, rivers, coasts, or other marine sites; Sealings or joints for engineering works in general
- E02B3/02—Stream regulation, e.g. breaking up subaqueous rock, cleaning the beds of waterways, directing the water flow
- E02B3/023—Removing sediments
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
- E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
- E02F3/92—Digging elements, e.g. suction heads
- E02F3/9212—Mechanical digging means, e.g. suction wheels, i.e. wheel with a suction inlet attached behind the wheel
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/88—Dredgers; Soil-shifting machines mechanically-driven with arrangements acting by a sucking or forcing effect, e.g. suction dredgers
- E02F3/90—Component parts, e.g. arrangement or adaptation of pumps
- E02F3/92—Digging elements, e.g. suction heads
- E02F3/9212—Mechanical digging means, e.g. suction wheels, i.e. wheel with a suction inlet attached behind the wheel
- E02F3/9225—Mechanical digging means, e.g. suction wheels, i.e. wheel with a suction inlet attached behind the wheel with rotating cutting elements
- E02F3/9237—Suction wheels with axis of rotation in transverse direction of the longitudinal axis of the suction pipe
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F5/00—Dredgers or soil-shifting machines for special purposes
- E02F5/28—Dredgers or soil-shifting machines for special purposes for cleaning watercourses or other ways
- E02F5/287—Dredgers or soil-shifting machines for special purposes for cleaning watercourses or other ways with jet nozzles
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Architecture (AREA)
- Environmental & Geological Engineering (AREA)
- Ocean & Marine Engineering (AREA)
- Cleaning In General (AREA)
Abstract
A machine for cleaning reclamation channels from deposits comprises an undercarriage supporting a gas flow generator 1 having a guide nozzle 2 and a reflecting screen 3 connected to the guide nozzle 2. The guide nozzle 2 has a movable portion 4 of a configuration corresponding to the cross-sectional shape of the channel being cleaned. Flexible rippers 5 are attached to the edge of the outlet end of the movable portion 4 of the nozzle 2. The screen 3 is hinged to the movable portion 4 of the nozzle 2. The machine can most advantageously be used for removing deposits from reclamation channels having anti-seepage linings. <IMAGE>
Description
SPECIFICATION
Machine for Cleaning Reclamation Channels from Deposits
The present invention relates to machines for cleaning reclamation channels from deposits.
The invention may be most advantageously used for removing deposits from reclamation channels having an anti-seepage lining.
According to the invention, there is provided a machine for cleaning reclamation channels from deposits, the machine comprising a displaceable support supporting a gas flow generator having a guide nozzle for feeding a gas jet under pressure to deposits accumulated in a channel, a reflecting screen connected to the guide nozzle and preventing a chaotic spreading of the jet, the guide nozzle having a movable portion which has a configuration corresponding to the crosssectional shape of the channel being cleaned, and flexible rippers installed on the movable portion of the nozzle, the screen being hinged to the movable portion of the nozzle.
Each ripper is preferably hinged to the movable portion of the nozzle and comprises a length of chain having pivotally interconnected links.
The reflecting screen may comprise plates which are mounted in such a manner that there is provided a space therebetween for the removal of deposits separated from the channel surface.
A knife may be installed on the movable portion of the nozzle for undercutting the layer of deposits being removed, the knife being so positioned that its leading surface is at an angle of at least 900 to the nozzle axis in the plane extending at right angles to the cutting path.
The knife, nozzle and screen plate are preferably arranged in a single line along which deposits are removed from the channel.
This construction of the machine enables the cleaning of channels of varying depth and width from deposits in any season, including winter, without damaging anti-seepage linings.
Owing to the fact that the guide nozzle is provided with a movable portion having a configuration corresponding to the crosssectional shape of the channel being cleaned, a permanent engagement of the working zone of the jet with the face is ensured when removing deposits from reclamation channels of varying depth and width without damaging their antiseepage linings.
As flexible rippers are attached to the edge of the outlet end of the movable nozzle portion, it becomes possible to intensify the face breaking operations, the separation of particles of compacted deposits from the channel surface and the entraining of them into the zone of transportation of the jet.
Due to the fact that the screen is hinged to the movable portion of the nozzle, the zone of unproductive spreading of the jet is reduced with the removal of differing layers of deposits from channels of varying depth and width.
When each ripper is hinged to the movable portion of the nozzle, oscillating movement of the rippers is possible so that the free end of each ripper can impart an impact action to the layer of compacted deposits and, if each ripper comprises a length of a chain having pivotally interconnected links, the ripper has an increased number of degrees of freedom and is capable of performing pulsed oscillations at an increased frequency of impact action on the face.
When the reflecting screen comprises plates, the jet may be screened on several sides to reduce its unproductive spreading outside the face, and, as there is provided a space between the plates for the removal of deposits separated from the channel surface, the velocity of the jet flow removing the deposit particles from the channel may be controlled thus improving the accuracy of the removal.
When a knife for undercutting the layer of deposits being removed is attached to the movable portion of the nozzle, deposits may be removed from channels having a soft soil and film lining. If the leading surface of the knife is at an angle of at least 90" to the nozzle axis in the plane extending at right angle to the cutting path, the removal of the cut off layer of deposits with the gas jet to beyond the limits of the channel, and reduction of gas consumption, is ensured.
When the knife, nozzle and screen plates are arranged in a single line along which deposits are removed from the channel, a directed removal of deposits from the channel is ensured with the possibility of variation of the removal direction during cleaning.
The invention will now be further described, by way of example, with reference to the accompanying drawings, in which:
Figure 1 is a general view of a machine for cleaning reclamation channels from deposits illustrating diagrammatically the relative arrangement of a gas flow generator mounted on an undercarraige and a guide nozzle having a movable portion;
Figure 2 is a general plan view of part of the machine of Figure 1;
Figure 3 is a sectional view taken along the line Ill-Ill in Figure 1 showing the relative arrangement of plates of a reflecting screen and flexible rippers, and the movable portion of the nozzle;
Figure 4 is a sectional view taken along the line IV--IV in Figure 1;
Figure 5 shows the attachment of flexible rippers;
Figure 6 shows another embodiment of the movable portion of the nozzle;;
Figure 7 is a view taken in the direction of arrow A in Figure 6 to show the movable portion of the nozzle having a knife for undercutting the layer of deposits being removed;
Figure 8 is a general side elevation view of a machine in the transportation position; and
Figure 9 is a plan view of the machine of Figure 8.
The machine for cleaning reclamation channels from deposits (Figures 1, 2) comprises a gas flow generator 1 supported on an undercarriage of a support vehicle. A guide nozzle 2 is attached to the generator 1 for feeding a gas flow under pressure to deposits accumulated in a channel, and a reflecting screen 3 is connected to the guide nozzle 2 and prevents the gas jet from spreading chaotically.
The guide nozzle 2 (Figures 3, 4) is provided with a movable portion 4 to which the screen 3 is hinged so as to reduce the zone of unproductive spreading of the jet in removing deposits of varying thickness from channels. The configuration of the movable portion 4 of the nozzle 2 corresponds to the cross-sectional shape of the channel being cleaned thereby providing a permanent engagement of the working zone of the jet with the face when removing deposits from reclamation channels of varying depth and width without damaging their anti-seepage lining.
Flexible rippers 5 are attached to the outlet edge of the movable portion of the nozzle 2 to intensify the breaking of the face, the separation of particles of compacted deposits from the channel surface and their entraining in the zone of transportation of the jet. The movable portion of the nozzle bears against the channel lining surface by means of self-positioning roliers 6.
Each ripper (Figure 5) is mounted for oscillations so that the free end of each ripper can impart an impact action to the layer of compacted particles, and for that purpose, the ripper is hinged to the movable portion 4 of the nozzle 2 and comprises a length of chain having links 7 which are pivotally connected to one another.
Thus the number of degrees of freedom of the ripper is increased, and the ripper can perform pulsed oscillations at an increased frequency of impact action. The flexible rippers 5 may also comprise lengths of cable or ropes of materials stable at high temperature.
The reflecting screen 3 comprises plates (Figure 3) which are arranged in such a manner that there is provided a space between them and the channel surface and face slope for removal of deposits separated from the channel surface. This facility enables the control of the velocity of the jet flow removing the deposit particles beyond the limits of the channel and improves the accuracy of removal.
In a second embodiment, a knife 8 is attached to the movable portion 4 of the nozzle 2 (Figures 6, 7) to undercut the layer of deposits being removed. The knife is so positioned that its leading surface is at an angle a to the nozzle axis (a is at least 90 ) in the plane extending at right angles to the cutting path. Thus, deposits may be removed from channels having soft (soil and film) linings as the gas jet blows the deposits off the knife surface, rather than from the lining.
Furthermore, this facility enables the reduction of specific gas consumption as the gas entrains and blows the soil off over the entire cross-section of the nozzle.
To ensure a directive removal of the deposits during cleaning, the knife 8, the nozzle 2 and one of the plates of the screen 3 are arranged in a single line along which the deposits are removed from the channel, the second plate of the screen 3 being hinged to the first plate by means of a tie rod 9 to define a space therebetween which can be varied in cross-section to control the velocity of the deposit carrying flow. To change the direction of deposit removal from one side of the channel to the other, there are provided baffles 10 articulated between the plates of the screen 3, which deflect the jet flow, the baffles being driven by a hydraulic cylinder 11.
The machine for cleaning reclamation channels from deposits functions in the following manner.
Before the beginning of operation, the support vehicle is wheeled up to the edge of the channel and positioned for movement in the direction along the channel during cleaning. Then the guide nozzle 2 is lowered into the channel, and subsequently the movable portion 4 thereof is extended by means of a hydraulic cylinder 1 2 to bring the extremity of the outlet end thereof to a position adjacent the layer of deposits to be removed from the channel. The nozzle 2 and the movable portion 4 thereof are supported by means of self-positioning rollers 6 to bear against the channel lining. The screen 3 is brought by means of a hydraulic cylinder 13 into a position corresponding to the thickness of deposits in the channel, and the flexible rippers 5 engage the layer of deposits.
The cleaning proper of the channel is then begun by turning on the gas flow generator 1 which feeds a gas flow to the guide nozzle 2 and its movable portion 4 to form, at the outlet end thereof, a high-velocity air and gas jet. At the outlet of the movable portion of the nozzle 2, the jet starts acting on the layer of deposits to separate the particles from the face and blow them off beyond the limits of the channel and from the channel lining surface.
The jet is reflected by the screen plate 3 which covers it from the top and directs the jet against the deposit layer. At the same time, the jet which flows out of the outlet end of the movable portion 4 of the nozzle 2 at high velocity creates a reduced pressure at the edges so that the flexible rippers 5 are caused to move into the jet flow.
When in the high-speed gas jet flow, the flexible rippers 5 perform oscillations so that their links 7 hit the layer of deposits to disintegrate it, thereby accelerating the separation of deposit particles from the layer and contributing to more rapid entraining thereof in the zone of the jet. It should be noted that the smaller the size of the ripper links, the better is their flexibility and the higher their frequency of impact action on the layer of compacted deposits.
This impact action which is obtained without any additional power driven means enables the deposits to be loosened and a starting velocity to be imparted to the particles to facilitate the removal of particles by the gasand air jet and to improve the solid content of the suspension. Thus the cleaning process is intensified.
As the deposit particles are blown off, the lining surface is cleaned from the layer of deposits, and a face is formed along the entire width of the channel. Another plate of the screen 3 is extended from the side opposite to the face by means of a hydraulic cylinder 14 to prevent the jet from chaotically spreading. Therefore, the gas jet is concentrated (compressed) so as to act directly on the deposit layer. By changing the position of the plates of the screen 3, the crosssectional area of the space defined between these plates, the channel lining and the face slope may be varied, thereby controlling the velocity of the gas and air flow -at the contact with the face during cleaning. The support vehicle is then moved in the working position along the channel to remove the deposits beyond the limits of the channel.After the cleaning is over, the guide nozzle with the movable portion and the screen plates are withdrawn from the channel with the reversed order of operations and brought into the transportation position (Figures 8, 9) by means of hydraulic cylinders 14, 13, 12, 15, 1 6. The machine is then moved to the next channel for cleaning.
Where it is necessary to remove deposits from a channel having a soil and film lining, another embodiment of the movable portion of the nozzle is used, which functions in the following manner.
Before the beginning of cleaning, when the machine is set into the working position, the movable portion of the nozzle is extended in such a manner that the knife should be plunged at a thickness of the layer of deposits to be removed.
The screen plates are installed in a position providing an angle p required for throwing the deposits beyond the limits of the channel. The deflecting baffles 10 are fixed in a position directed to one or other side of the channel by means of the hydraulic cylinder 1 Then the gas flow generator is turned on, and the cleaning of the channel begins. As the machine moves along the channel, the knife which has a configuration corresponding to the cross-sectional shape of the channel undercuts the layer of deposits, and it does so in such a manner as not to disturb the layer of soil protecting the anti-seepage film lining. As a result, soil is fed to the nozzle 2 along the leading surface of the knife.The gas jet flow under pressure fed from the generator through the movable portion to the outlet end of the nozzle entrains the deposits coming to the nozzle from the knife. In this embodiment the outlet end of the movable portion of the nozzle is arranged above the knife and spans the entire width of the leading surface thereof so that the layer of deposits is completely displaced from the knife to the nozzle, and the gas flow blowing through this layer of deposits will do useful work utilizing the entire flow rate. Since the angle a between the leading surface of the knife and the nozzle axis is greater than 90 , the gas jet is directed upwardly and, as the knife, nozzle and one of the screen
plates are arranged in a single line, the deposits
entrained by the jet are removed upwardly
beyond the limits of the channel, along the screen
plate.It should be noted that the other screen
plate which is attached to the first plate defines an inner space therewith through which the suspension-forming gas jet is blown, thereby
preventing the chaotic spreading of deposits and
improving the accuracy of removal.
Owing to the pivotal interconnection of the
screen plates the cross-sectional area of the inner
space defined therebetween may be varied.
By adjusting the position of the screen plates,
e.g. by means of a screw-type tie rod (not shown
in Figure 6), the distance the deposits are thrown
out of the machine may be varied, their disposal
may be duly organized, or they may be loaded in vehicles. The suspension flow passing through the
inner space between the screen plates may be
directed to one or other side of the channel by turning the deflecting baffles 10 by means of the
hydraulic cylinder 11, depending on local
conditions for soil disposal.
When compacted deposits are removed, they are fed along the leading surface of the knife to the nozzle in the form of lumps. In such case the flexible rippers which are hinged to the outlet end of the movable portion of the nozzle oscillate in the high-speed gas flow to disintegrate the lumps thereby contributing to the entraining of the deposit particles with the jet and intensifying the cleaning process.
As will be apparent from the description, the described machine for cleaning reclamation channels from deposits has the construction which improves the efficiency of cleaning owing to:
a) intensification of the process, improvement of the performance and quality of cleaning of lined channels;
b) reduction of specific gas consumption and energy requirements for generation of gas jet;
c) improvement of the accuracy of removal of deposits;
d) removal of any type of deposits, including those overgrown with plants, in any season without damaging the surface or anti-seepage lining of channel.
Claims (6)
1. A machine for cleaning reclamation channels from deposits, the machine comprising a displaceable support supporting a gas flow generator having a guide nozzle for feeding a gas jet under pressure to deposits accumulated in a channel, a reflecting screen connected to the guide nozzle and preventing a chaotic spreading of the jet, the guide nozzle having a movable portion which has a configuration corresponding to the cross-sectional shape of the channel being cleaned, and flexible rippers installed on the movable portion of the nozzle, the screen being hinged to the movable portion of the nozzle.
2. A machine as claimed in Claim 1, wherein each ripper in hinged to the movable portion of the nozzle and comprises a length of chain having pivotally interconnected links.
3. A machine as claimed in claim 1 or claim 2, wherein the reflecting screen comprises plates which are arranged in such a manner as to define a space therebetween for the removal of deposits separated from the channel surface.
4. A machine as claimed in any preceding claim, wherein a knife is attached to the movable portion of the nozzle for undercutting the layer of deposits being removed and positioned so that its leading surface is at an angle of at least 900 to the nozzle axis in a plane extending at right angle to the cutting path.
5. A machine as claimed in any preceding claim, wherein the knife, nozzle and screen plate are arranged in a single line along which deposits are removed from the channel.
6. A machine for cleaning reclamation channels from deposits, substantially as herein described with reference to, and as shown in the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB7900232A GB2038902B (en) | 1979-01-04 | 1979-01-04 | Machine for cleaning reclamation channels from deposits |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB7900232A GB2038902B (en) | 1979-01-04 | 1979-01-04 | Machine for cleaning reclamation channels from deposits |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2038902A true GB2038902A (en) | 1980-07-30 |
| GB2038902B GB2038902B (en) | 1982-11-10 |
Family
ID=10502308
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7900232A Expired GB2038902B (en) | 1979-01-04 | 1979-01-04 | Machine for cleaning reclamation channels from deposits |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2038902B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0105570A1 (en) * | 1982-10-05 | 1984-04-18 | Van Hattum En Blankevoort B.V. | Method and apparatus for removing mud from below an underwater construction |
| NL1005330C2 (en) * | 1997-02-20 | 1998-08-24 | Dredging Int | Method for making a trench below the waterline and device for this. |
| CN115404935A (en) * | 2022-11-02 | 2022-11-29 | 无锡恒诚水利工程建设有限公司 | Ecological dredging equipment for comprehensive remediation of rivers and lakes and dredging method thereof |
-
1979
- 1979-01-04 GB GB7900232A patent/GB2038902B/en not_active Expired
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0105570A1 (en) * | 1982-10-05 | 1984-04-18 | Van Hattum En Blankevoort B.V. | Method and apparatus for removing mud from below an underwater construction |
| NL1005330C2 (en) * | 1997-02-20 | 1998-08-24 | Dredging Int | Method for making a trench below the waterline and device for this. |
| EP0860556A1 (en) * | 1997-02-20 | 1998-08-26 | Dredging International N.V. | Method for making a trench under water and device therefor |
| CN115404935A (en) * | 2022-11-02 | 2022-11-29 | 无锡恒诚水利工程建设有限公司 | Ecological dredging equipment for comprehensive remediation of rivers and lakes and dredging method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2038902B (en) | 1982-11-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |