SE507502C2

SE507502C2 - Cleaning device for press rolls in a pulp machine

Info

Publication number: SE507502C2
Application number: SE9603657A
Authority: SE
Inventors: Stefan Mattsson
Original assignee: Sunds Defibrator Ind Ab
Priority date: 1996-10-07
Filing date: 1996-10-07
Publication date: 1998-06-15
Also published as: SE9603657D0; SE9603657L

Abstract

A device for the on-line cleaning of press rolls (11) comprises at least one nozzle (16) emitting a high pressure jet. The nozzle faces the centre of the roll and is moved backwards and forwards in an axial direction over the roll periphery. Preferably nozzle speed and jet width are set according to the roll rotation speed in order to create a cleaning pattern with an overlapping screw line shape. Hot water is impinged against the roll at 100-300 bar and 30-90 deg C.

Description

15 20 25 30 35 507 -fgê If- radiell led mot valsarna 11. 15 20 25 30 35 507 -fgê If- radial joint towards the rollers 11.

Varje munstycke 16 är anordnad på en skyttel 18, som är fram och åter rörlig utmed en gejdbalk 19. Skyttlarna 18, vars antal bestämmes av valsens längd och den rengörings- tid per omlopp som kan accepteras, drives fram och åter utmed gejdbalken 19 av ett drivelement 20, exempelvis i form av en kedja, rem, kuggrem, band e.d. här visat som kedja. Denna drivkedja står i ingrepp med ett drivhjul 21 i gejdbalkens 19 ena ände och ett fritt roterbart kedjehjul 22 i gejdbalkens 19 andra ände. Drivhjulen 21 drives av varsin reversibel elmotor 23. Gejdbalken 19 är placerad i valsens rotations- riktning efter schaberbalken 18.Each nozzle 16 is arranged on a shuttle 18, which is reciprocated along a guide beam 19. The shutters 18, the number of which is determined by the length of the roller and the cleaning time per turn that can be accepted, are driven back and forth along the guide beam 19 by a drive element 20, for example in the form of a chain, belt, toothed belt, belt, etc. shown here as a chain. This drive chain engages a drive wheel 21 at one end of the guide beam 19 and a freely rotatable sprocket 22 at the other end of the guide beam 19. The drive wheels 21 are each driven by a reversible electric motor 23. The guide beam 19 is placed in the direction of rotation of the roller after the doctor beam 18.

De skilda skyttlarna 18 i varje gejdbalk 19 är inbördes förbundna med en stång (icke visad) och försörjes med högtrycksvarmvatten genom en högtrycksslang 24, som vid skyttlarnas 18 förflyttning i ena riktningen, nedåt i fig. 1, rullas upp på slangupprullare 25. I övrigt ses i planvyn i fig. 1 olika organ för alstring och transport av högtrycks- varmvatten, såsom ett filter 26, en säkerhetsvakt 27, högtryckspumpar 28, tryckregulatorer 29, elvärmare 30 och säkerhetsventiler 31.The different shuttles 18 in each guide beam 19 are interconnected by a rod (not shown) and are supplied with high-pressure hot water through a high-pressure hose 24, which when the shuttles 18 move in one direction, downwards in Fig. 1, is wound up on hose reels 25. Otherwise seen in the plan view in Fig. 1 various means for generating and transporting high-pressure hot water, such as a filter 26, a safety guard 27, high-pressure pumps 28, pressure regulators 29, electric heaters 30 and safety valves 31.

I fig. 3 ses ett tvärsnitt genom en platt stråle 17 från munstycket 16. Munstyckets 16 rörelsehastighet och hög- trycksstrålens 17 bredd anpassas till valsens 11 varvtal så, att rengöringsmönstret på valsen bildas av en tät skruvlinje med överlappning. Högtrycksstrålen 17 har alltså sin längsta utsträckning i munstyckets 16 rörelseriktning. Högtrycks- varmvattnet har lämpligen ett tryck på 100-300 bar, lämpligen 150-200 bar, och en temperatur på 30-90°C, lämpligen 60-90°C.Fig. 3 shows a cross section through a flat jet 17 from the nozzle 16. The speed of movement of the nozzle 16 and the width of the high-pressure jet 17 are adapted to the speed of the roller 11 so that the cleaning pattern on the roller is formed by a dense overlapping helix. The high-pressure jet 17 thus has its longest extent in the direction of movement of the nozzle 16. The high-pressure hot water preferably has a pressure of 100-300 bar, preferably 150-200 bar, and a temperature of 30-90 ° C, preferably 60-90 ° C.

Anordningen styrs lämpligen av valspressens trågtryck, dvs trycket i tråget under valsarna, som avtätas uppåt medelst ett tätningsbord 32, eller av en förprogrammerad tid, som beror av inkrusteringsgraden i den aktuella processen.The device is suitably controlled by the trough pressure of the roller press, ie the pressure in the trough under the rollers, which is sealed upwards by means of a sealing table 32, or by a pre-programmed time, which depends on the degree of incrustation in the process in question.

Genom anordningen enligt uppfinningen möjliggöres en rengöring av pressvalsarna under drift, så att stille- stånd med därav följande produktionsbortfall undvikes.The device according to the invention makes it possible to clean the press rollers during operation, so that downtime with consequent loss of production is avoided.

Rengöringen sker automatiskt utan manuellt ingrepp.The cleaning takes place automatically without manual intervention.

Claims

10 15 20 25 30 35 ~: - šsov 502 PATENTKRAV

A device for cleaning during operation of press rollers with a perforated jacket for dewatering pulp, characterized by at least one nozzle (16) for emitting a high-pressure jet (17), which nozzle (16) is reciprocally movable in axial joint along the periphery of a roller (11) without abutment against the roller and directed towards the center of the roller.

Device according to claim 1, characterized in that the speed of movement of the nozzle (16) and the width of the high-pressure jet (17) are adapted to the speed of the roller (11) so that the cleaning pattern is formed by a tight overlapping helix.

Device according to Claim 1 or 2, characterized in that the high-pressure jet (17) is flat with its longest extension in the direction of movement of the nozzle (16).

Device according to one of Claims 1 to 3, characterized in that the high-pressure jet (17) consists of hot water.

Device according to claim 4, characterized in that the hot water has a pressure of 100-300 bar and a temperature of 30-90 ° C.

Device according to claim 4 or 5, characterized in that each nozzle (16) is arranged on a shuttle (18), which is reciprocable along a guide beam (19), placed in the roller (11) direction of rotation according to a doctor blade (14) located on the roller.

Device according to Claim 6, characterized in that the shuttles (18) movable along the guide beam (19) are interconnected and connected to a drive element (20) which engages with a drive wheel (21) in the guide beam. (19) one end and a freely rotatable sprocket (22) at the other end of the guide beam (19).

Device according to one of Claims 1 to 7, characterized in that its function is controlled by the tray pressure of the press or by a pre-programmed time, which depends on the degree of incrustation in the process in question.