FI114937B - Method for locking the intermediate roll of a multi-roll calender - Google Patents

Description

114937

The present invention relates to paper and board machines, in particular calenders. More particularly, the present invention relates to a method of locking the intermediate roll of a multi-roll calender relative to the calender body.

It is known that the calender intermediate roll can be locked to the calender body by means of overload pins 10 which, in the event of an overload, break, preventing the calender roll mounting structures from failing. The intermediate roll will then rest on its mounting structures and fixed supports on the calender body, from where the intermediate roll will need to be lifted back to the correct height and locked in place with new breakers.

When polishing a paper web, the paper web is guided through a calender, which provides a web extension where the web is processed in nipples, such as nips between a calendering roll pair of a multi-roll calender. The roll stack, in which the rolls are movable in nip contact with each other for calendering the fibrous web in closed nipples, includes a calender roller top roller and a lower roller, at least 20 of which are resiliently coated and act as a back roll for hard and smooth press rolls and at least wherein, in the roll stack, the center axes of the calender rolls are parallel and transverse to the direction of the web CD so that between the adjacent calender rolls which form the calender roll pair is a web calendering nip with a compression line or plane of the calender roll rolls.

:, In this context, calender rolls refer to rolls forming a calendering nip, "top roll" means the top roll of a roll stack, bottom roll means a roll stack: ": 30 lowest roll, top nipple means the top calendering nipple formed by top:"; between the roll and the calender roll below the upper roll, the nip refers to the lowest 2 114937 calendering nips formed between the lower roll and the calender above the lower roll, and the top thermo roll is the lower roll roll thermocouple. The calendering rollers between the top calender roller and the lower roller are referred to herein as intermediate rolls. The calendering nips 5 between the top calendering nip and the calendering nip are referred to herein as spacers. The intermediate roll may be a hard surface or a flexible surface, and the intermediate roll may be a thermal, polymeric, fiber or composite roll.

Typically, compression is accomplished in a multi-roll calender by securing the top or bottom roll of the roll stack 10 and squeezing the stack of rolls against a fixed roll, which in place may be a top roll, a lower roll, or some of the spacers. Alternatively, both the upper and lower rollers are pressed against each other either so that neither of the intermediate rolls is locked in place or at least one of the intermediate rolls is locked in place. The deflections of the rolls can generally be compensated by deflection compensation devices in the upper and lower rolls, for example, so that the roll nipples take a straight line shape.

One roll stack of an on-line multi-roll calender unit typically has at least three rolls and two nips. Between two calendering rolls:. A frequently used support solution to enable the opening and closing of the 20 nips is to support at least one calendering roll with a pair of calendering rolls at each end: by means of attachment structures to the calender body, such as brackets and loading arms allowing vertical movement of the calendering roll. In the calendars, the transverse line load increases in direction of the web from the upper nip to the lower nip due to the earth's attraction. To eliminate this downward line pressure, to control the roll deflection line, and also to quickly open the roller, current multi-nip calendars utilize a ground and roller compensating roller relief provided by a cylinder and a lever mechanism. One such roll relief system is OptiLoad ™ -: ':': 30 in the calendars described in FI96334.

«· * 3 114937

The modern calender is subject to high demands on the calendering method. Multiple grades of different paper types require flexible alternative ways to load the calender roller as well as different calendering methods. This has facilitated the introduction of various load-adjustable nipples and different types of roll coverings on the calendars.

The Applicant's Finnish Patent Application FI20030002 discloses a multi-roll lantern which aims to provide flexibility in calendering different types of fiber web grades as well as partial nip runs. Flexibility refers to the ability to change the arrangement of calendering nips in a multi-roll calender and the export path of a fiber web in a dairy application, whereby utilizing different combinations of nip assemblies and / or web export paths allows for flexibility in ignoring or changing rolls.

Applicant's Finnish patent application FI 20030004 discloses improving and expanding the calendering potential of the web and the flexibility of the calendering, i.e. the possibilities of providing different paper grades with a single nip calender, where nipple loads can be adjusted and / or optimized and / or optimized. closure.

<I «·» ·: '. The caliper intermediate roll fastening structures, such as the carrying and loading arms, are known to be equipped with a breaker shock to overload the intermediate roll. The intermediate roll nipple, which may be a top nipple, a spacer nipple, or: · a 'bottom nip', in the event of an overload, breaks the pins to prevent '; * 'Failure of intermediate roller mounting structures. In this case, said intermediate roll is left resting against the fixed supports of the frame by its fixing edges. In order to load said nipple again when it is involved in calendering, for example,! : 30 partial nip drives, said intermediate roll must be brought back to the correct height desired f; to said calendering station and said intermediate roll must be locked fixedly with respect to calender 4 114937. In this case, for example, said intermediate roll must be pushed to the right height by its mounting structures so that the intermediate roll mounting structures, such as lever arms and load arms, can be locked in place with new break-in pins.

5

The calendars exhibit problematic roll and nip vibration while driving, which is accentuated by the combined effect of some height and load adjustable roll support solutions and the required high line loading and / or inhomogeneous web material. In particular, high line loads may occur at the top nip. In the case where the top nip is the first to receive a fibrous web fed into the calender, which exhibits an inhomogeneity prior to calendering e.g. thickness, the fibrous web evokes nipple vibration. Upper thermal roll! the support thus contributes significantly to the vibration situation of the whole calender.

15 The calender intermediate roll shall be capable of being locked to the body of the multi roll calender to allow for partial nipple travel and to reduce running vibration. The disadvantage of locking the intermediate roller to the calender body by means of breakage shocks is the disadvantage of driving after a breakage in the event of an overload situation: short-term overloading because the intermediate roller must be lifted with separate lifting means such load-> '· The arms can be locked in with new break-in shafts as a manual step. Calendering: The calendering has to be interrupted and valuable calendering time is lost.

25 The locking of the intermediate roll firmly to the calender body must be done: 'in such a way that the overload caused by the interruption of the driving is quickly desired' 'and the driving can be resumed as quickly as possible with the least amount of manual work.

♦ »» »5 114937

In general, the object of the present invention is to eliminate or at least reduce the disadvantages, limitations and weaknesses of prior art locking of a multi-roll calender intermediate roll.

It is an object of the present invention to provide a new and inventive method for solving or at least reducing the above-mentioned problems and drawbacks and for implementing a locking of the intermediate roller of a multi-roll calender firmly on the calender body to allow partial nipples

10

The method of the invention is generally characterized in that the at least one intermediate roll of a multi-roll calender is supported on the calender body by double-sided cylinders, such a cylinder comprising at least one pushing chamber and at least one pulling chamber, Driving chamber such that, depending on the direction of the overload, the pushing chamber or the drawing chamber is discharged in the event of an overload.

; Preferably, according to an embodiment of the invention, the chamber of the double-sided cylinder which has been disassembled is pressurized once the overload condition has been removed.

According to one embodiment of the invention, the pressurized chamber of the double-sided cylinder communicates with the overload protector which is triggered in the overload space.

According to one embodiment of the invention, an overload valve is connected to the cylinder chamber for overload protection.

I> »6 114937

A further embodiment of the invention is that the multi-roll calender has at least one thermal roll, wherein at least one thermal roll is supported and locked relative to the calender body.

According to one embodiment of the invention, the at least one polymer, composite or fiber roll is supported and locked relative to the calender body.

According to one embodiment of the invention, the multi-roll calender has an upper label roll and a lower thermal roll, between which the intermediate roll is supported and locked relative to the calender body 10.

According to one embodiment of the invention, the hydraulic oil in the cylinder chamber is pressurized at a higher than normal pre-pressure to increase the stiffness of the support.

! 15

According to one embodiment of the invention, the cylinder is secured at its pushing chamber-side pushing end to the intermediate roll bearing housing or mounting structure and the pulling chamber-side pushing end to the calender; ': To the body.

: '.. 20 | * The locking of the intermediate roll in accordance with the invention with the calender body with a double-sided overload cylinder provides the advantage, compared with the prior art, of a faster return to normal running from a malfunction caused by an overload condition in the calender nip. Once the overload problem has been eliminated, the two-to-25-sided cylinder that allows the intermediate roll to lock to the calender body can be re-pressurized and calendering, e.g., partial nip driving, can be resumed quickly. Locking the intermediate roll to the calender body with double sided! furthermore, the advantage of prior art is that the calender's runtime vibrations are reduced by using a pressure higher than that corresponding to the load.

7, 114937

Raising the intermediate roll to the right height to start driving does not require separate lifting means for the intermediate roll or intermediate roll, such as fixing arms or levers, to lock the intermediate roll to the correct height, but raising the intermediate roll to the right height and locking it in position with 5 caliper body

Raising the intermediate roll to the right height and locking it to the calender body to start driving requires fewer manual steps, such as installing break-in shocks, which also improves safety at work.

The method according to the invention can advantageously lock the thermo roll, such as the top thermo roll, the lower thermo roll, or any other caliping nip thermo roll, which enables a partial nipple travel of the multi roll calender. The Monite-15 lacquer calender may have a plurality of nipple-enabling nipples in which the intermediate roll calendering roll is, for example, a deflection compensated roll, such as and the color of the upper roller and the lower roller; *. 20 intermediate rolls, eg thermo roll.

; * '; The invention will now be described with reference to the accompanying drawings, in which the process of the invention is illustrated, without limiting the invention '; exclusively as shown in the figures.

25 ': Fig. 1 shows a five-roll and four-nip roll stack of a multi-roll calender with an intermediate roll, preferably an upper thermal roll, provided with an overload cylinder.

Figure 2 illustrates, in simplified form, an overload cylinder of a multi-roll calender for locking an intermediate roll with respect to the body of a multi-roll calender according to the invention.

8 114937

Fig. 3 shows the lower nip of the roll stack of Fig. 1, in which the lower thermal roller on the intermediate roll is provided with an overload cylinder.

Figure 1 schematically illustrates a multi-roll calender 10, in particular a 5 roll stack comprising a top roll Ila and a lower roll 15, and three intermediate rolls 12, 13,14 interposed between the top and bottom rolls, the top, bottom and intermediate rolls forming roll stack calendering rolls 11-15. In the roll stack, adjacent calendering rolls 11.12; 12.13; 13,14 and 14,15 form calendering roll pairs, wherein the calendering rolls each form a fibrous web calendering nip 1, 2, 3 and 4 with reference numerals 10 in FIG.

In the multi-roll calender 10, compression of the fibrous web can be achieved by either securing the top roll 11, lower roll 15 or one of the intermediate rolls 12, 13, 14 of the roll stack relative to the calender body described by the the fixed roll may be a top roll 11, a lower roll 11 or, for example, one or some of the intermediate rolls 12, 13, 14. Alternatively, both the top roll and the bottom roll are pressed against each other either so that neither; the intermediate rollers are not locked in place or at least one of the intermediate rolls 20 is locked in place. In many solutions, the compressive forces of the upper roller 11 and / or the lower roller 15 can be independently adjusted. Upper roller and / or lower roller: may be provided with loading equipment imaged inside the jacket and / or the upper roller may be loaded by an overhead loading cylinder and / or the lower roller may be: loaded by a lower loading cylinder. The deflections of the rolls can be compensated by deflection compensators on the rolls, for example, so that the deflection lines of the rolls are of the same shape. Deflection compensating devices are typically provided in the upper and / or lower roll, but also one of the intermediate rolls may be provided with deflection compensating means.

f * 30 In Figure 1, the roll stack of the multi-roll calender 10 is shown in a position where '; only the upper nipple 1 is closed and the intermediate nipples 2, 3 and the lower nipple 4 are open. Monitors> 9 114937 Upper and lower roller supports for lacquer calender 10 are not shown. The multi-roll calender may have at least one thermal roll which is supported and locked relative to the mandrel F in the intermediate roll. Further, the multi-roll calender may have at least one polymer, composite or fiber roll as an intermediate roll, for example the intermediate roll 13 shown in Figure 1. The bearing housings H of the intermediate rolls 12, 13 and 5 14 are dotted. The bearing housings H are not removably and secured to the attachment structures 16, i.e., the support and load arms, of the intermediate rolls 12,13 and 14, which are mounted on the body F of the multi-roll calender 10 in FIG. 1. the load arms allow the intermediate rollers 12, 13 and 14 10 to move in their vertical position. In the roll stack of Figure 1, the vertical movement of the intermediate roll 12 as a calendering roll of the upper roll 11, which for example is the upper thermal roll, the lower intermediate rolls 13 and 14, and possible load relief are enabled by known load and bearing a vertical movement of the upper intermediate roll 12 and locking relative to the F of the multi-roll calender is made possible by the cylinders 18 pivoted on the one hand on the support and load arms 16 and on the other on the calender body F.

Fig. 2 is a simplified view of the cylinder actuator of the multi-roll calender 10, referred to in this application as a shorter cylinder 18, whereby the upper intermediate roll 12 of the roll stack relative to the F of the multi-roll calender can be locked; can be locked by the lowest spacer 14 of the roll stack, which may be a lower thermal roll, with respect to the F of the multi-roll calender. The cylinder 25 18, which is preferably a hydraulic cylinder, comprises a cylinder body 18 'provided with two chambers separated by an intermediate structure 18', of which; In the position shown in Figures 1 and 2, the lower chamber is denoted by reference numeral 21 and the upper chamber by reference numeral 22. The cylinder 18 further comprises a 'piston 19' followed by a chamber: a piston rod 19 for securing the lower end of the cylinder 18; the cylinder 18 comprises a crank

»I

10 114937 22 is a piston 20 'having a retaining loop at the end of the piston rod 20 for securing the upper end of the cylinder 18.

When the lower chamber 21 is pressurized, the piston 19 'of the cylinder 18 is pressed against the intermediate body 18' of the cylinder body 5 and the cylinder piston rod 19 retracts at most by the stroke of the piston 19 'into the body 18'. Thus, the cylinder chamber 21 may also be referred to as the pulling chamber 21. When the upper chamber 22 is pressurized, the piston 20 'of the cylinder 18 diverges from the cylinder body intermediate structure 18' and the cylinder piston rod 20 extends upwardly from the stroke 18 '. The cylinder chamber 22 may thus also be referred to as a pushing chamber 22. According to the invention, the chambers 21, 22 of the cylinder 18 are pressurized such that, depending on the direction of the overload, the second load direction chamber is discharged when the overload valve is engaged. Thus, with the loading direction applied to the intermediate roll 12, 14 being compressive to the cylinder 18, the chamber 22 of FIG. 2 is discharged in the overload condition and respectively the loading direction applied to the intermediate roll is pulling the cylinder 18. :: The chamber 21 of the vion 2 would discharge in an overload situation. Thus, the method of ... 20 according to the invention can be used to lock the intermediate roll of a multi-roll calender With respect to the body such that the intermediate roll shown in Fig. 1 is lockable as well as the upper '; : against downward loading, whereby the multi-roll calender has the ability to: · make it possible to form a variety of alternative nipples that allow partial nip traction.

According to one embodiment of the invention, the effect of the elasticity of the hydraulic oil, i.e.; ** Compressed hydraulic oil in chambers 21, 22 and in the flow duct. the effect of the damping is eliminated by pre-compression at a higher load than normal load to increase the stiffness of the support. In this case, the locking of the cylinder 18 is formed by the rigid-30 two so that the locking is not vibration-sensitive, in order to reduce the running vibration of the calender. The overload valve is a valve that limits the pressure to a pre-set value of π 114937 and, when opened, allows the pressurized hydraulic fluid to flow out of the chamber 21, 22 of the cylinder 18 through the flow port 2Γ, 22 '

In the case illustrated in Fig. 1, the overload direction is preferably triggered by an overload valve which compresses the cylinder 18 and engages with the cylinder chamber 22, whereby hydraulic fluid flows out of the chamber 22 through the flow line 22 'into the flow pipe, etc. 18 and the overloaded upper nipple 1 opens.

10

It should be noted that although the double-sided cylinder 18 is shown in the figures in an embodiment where the cylinder 18 comprises two chambers 21 and 22, the cylinder 18 may also be otherwise implemented to pressurize the chambers of the cylinder 18 such that at least one of the chambers the chamber in a given load direction will dissolve when the overload protector has tripped. The cylinder may also include a plurality of chambers as shown in the figures for a single loading direction and a plurality of flow connections, for example to make a particular chamber bifurcated or bi-directional.

The cylinder 18 may also have an external fastening structure which is different from that shown in the figures, for example, the cylinder end may have, instead of a fastening loop, a so-called stud, thread, flange or other fastening arrangement known per se. calender roll mounting. · In the structure or bearing housing and on the calender body F.

25

1, the intermediate roll 12 of the multi-roll calender 10 is supported on the calender body F by means of double-sided cylinders 18. The fastening structures 16 of the intermediate roll 12 below the upper roller 11, such as the supporting and loading arms, are provided with double-sided cylinders in the upper nipple 1 in view of the overload condition of the intermediate roller 12. '. 30 at one end, which is pivotable at one end, i.e. the retaining loop of the piston rod 20 above the cylinder, to the retaining structure 16 of the intermediate roll 12 and the other end 12 of the cylinder piston rod 19 to the caliper body. In an overload situation on the upper nipple 1 or the fastening structures 16 of the intermediate roll 12, the upper chambers 22 of the double-sided cylinders 18 are depressurized, whereby the upstream load and the piston rod of the cylinder 18 and the piston This prevents the fastening structures 16 of the intermediate roll 12 from failing due to overload, and the intermediate roll 12 remains resting on the cylinders 18 with its fastening structures 16.

10

The problem caused by the Kim overload has been ignored and, if necessary, the upper roller 11 has been moved higher, the intermediate roll 12 is brought back to the desired height by the mounting structures 16 such as brackets and loading arms by pressurizing the calendering, for example, in part nip driving. By also pressurizing the second chamber of the cylinder 18, the intermediate roll 12 is locked firmly with respect to the body F of the multi-roll calender 10, each chamber of the cylinder 18 being pressurized, and nipple vibration detrimental to calendering can be reduced by rigid locking.

Figure 3 shows the bottom nipple 4 of the multi-roll calender 10 similar to Figure 1, in which an intermediate roll 14, for example a lower thermal roller, over the lower blade 15 is provided with an overloading cylinder 18. The bearing housings H are removably and secured to the fastening structures 16 and load arms mounted on frame F of the multi-roll calender 10. The fastening structures 16, i.e. support and load arms, articulated with the frame F allow the intermediate roll 14 to move / from its vertical position. Thus, in Fig. 3, vertical movement and locking of the lower intermediate roll 14 with respect to the multi-roll calender body F is enabled by cylinders 18 articulated on the one hand on the support and load arms 16 and on the other on the calender body F above the support and load arms 13. 114937 lella. The vertical movement of the intermediate roll 14 and the possible relief of the load may furthermore be imitated by loading and support cylinders known per se, not shown in Fig. 3, which are pivotally mounted on the support and load arms 16 and on the calender body F, support and load arm below.

In Figure 3, the lower nip 4 is intentionally shown as a separate closed nip, whereby it is suitable for example for partial nip driving. In Fig. 3, the overload is directed to the downwardly securing structures of the intermediate roll 14 as a lower roll calendering roller 14, whereby the overload valve which compresses the cylinder 18 in contact with the lower cylinder 22 is triggered 20 'and piston rod 20 extend a stroke length into cylinder 18 and the overloaded lower nip 4 is released from overload. The problem caused by the Kim over-15 load is ignored and, if necessary, the lower roll 15 is temporarily lowered, the intermediate roll 14 is brought back to the desired height on the desired calendering station by attachment structures 16 such as brackets and loading arms by repressurizing the cylinder 18 with overload protector loads the alanip .. 20 for calendering, for example, partial nip. By also pressurizing the second chamber, the intermediate chamber 14 of the cylinder 18 is fixedly locked relative to the body F of the multi-roll calender 10 ', whereby each chamber of the cylinder 18 is pressurized, and the occurrence of nipple vibration detrimental to calendering can be reduced. · Rigid locking of the lane support.

25

The invention has been described above by way of example only with reference to the figures in the accompanying drawings. However, the invention is not limited to what is described in the description and figures, but various embodiments of the invention may vary within the scope of the inventive idea defined in the appended claims.

·. *. 30

Claims (9)

A method of reading an intermediate roll in a multi-roll calender (10) relative to the calender body (F), which multiple roll calender has at least one roll stack, in which roll stack the roll rollers (11, 12, 13, 14, 15) can be displaced in nip contact with one another for calendering a fiber web in the closed nip (1, 2, 3, 4), the intermediate roller (12, 13, 14) being supported against the calender body by mediating fastening structures (16), such as support and load arms, characterized in that the at least one intermediate roll (12, 13, 14) in the plurality calendar (10) is supported against the calender body (F) by means of double-sided cylinders (18), the cylinder comprising at least one sliding chamber (22) and at least one pulling chamber (21), and the intermediate roll is read in a fixed position relative to the calender body by pressurizing the pushing chamber and / or the pulling chamber in the double-sided cylinder in such a manner that depending on the direction of a Overload the firing chamber or the pulling chamber empties itself in an overload situation. 2. A method according to claim 1, characterized in that the chamber (21, 22, 22) in the double-sided cylinder (18) which empties is pressurized again as the overload situation has prevailed. A method according to claim 1 or 2, characterized in that the pressurized! the chamber (21, 22) of the double-sided cylinder (18) is in communication with an overload guard, which is triggered in an overload situation. 25 4. A method according to claim 3, characterized in that an overload valve is provided in conjunction with the chamber (21, 22) in the cylinder (18). 17 114937 Method according to any of claims 1-4, characterized in that the multi-roller calendar has at least one thermal roller (12, 14), wherein at least one thermal roller (12,14) is supported and read in relation to the calender body (F). 5 Method according to any one of claims 1-5, characterized in that at least one polymer, composite or fiber roll (13) is supported and read in relation to the calender body (F). Method according to any of claims 1-6, characterized in that the lieri roller calender has an upper thermal roller (12) and a lower thermal roller (14), an intermediate roller (13) between these being supported and read in relation to the calender body (F). . Method according to any of claims 1-7, characterized in that the hydraulic oil in the chamber (21, 22) in the cylinder (18) is pressurized with a pre-pressure greater than the normal load to increase the stiffness of the support. Method according to any one of claims 1-8, characterized in that the cylindrical members (18) are fixed with the projecting end (20) on the side of the projecting chamber (22) · 20 at the bearing housing ( H) or the mounting structure (16) of the intermediate roller (12, 13, 14) and with the pulling end (19) on the side of the pulling chamber (21) at the casing? 1 landing bodies (F). t I · »t 1 1 · I ·» I 1