JPH032993B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides nonwoven fabrics suitable for single-tube or multi-tube drying devices such as paper machines, coating machines, and printing machines.
The present invention relates to a papermaking material drying barrel for heating and drying various papermaking materials such as paper, processed paper, and paperboard, and which is equipped with an axial heating degree adjustment device.

[Conventional technology]

In the drying equipment, etc., in order to adjust the widthwise moisture content distribution (hereinafter referred to as moisture profile) of the strip-shaped wet paper material, a humidifying device that sprays moisture such as steam, a heat ray irradiation device such as infrared rays, and a microwave irradiation device are used. Various papermaking material moisture profile adjustment devices are used, such as irradiation heating devices, electromagnetic induction heating devices, hot air blowing devices, and ventilation deflection devices. but,
These conventional devices not only have problems in terms of energy conservation, but also because they adjust the moisture profile by locally rapidly humidifying or rapidly heating the transition-wet paper material. There was a quality problem in that there was a risk of swelling, wrinkles, etc.

It is well known that heated steam is introduced into the interior of a rotatably supported cylindrical drying tube to heat and dry the paper material that moves on the outer peripheral surface of the drying tube. In this case, if the moisture profile can be adjusted at the same time as the paper material is heated and dried using the drying tube, the above-mentioned energy saving and quality problems will not occur. However, due to factors such as the flow of heated steam inside the drying cylinder, the ends of the drying cylinder (hereinafter referred to as the "edges") are generally more likely to be overheated than other parts, and therefore the paper material is It tends to not be heated and dried uniformly.

Therefore, drying cylinders disclosed in Japanese Patent Publication No. 39-904 and Japanese Patent Application Laid-Open No. 56-159390 were proposed. These drying cylinders are equipped with an annular weir extending in the circumferential direction near the end of the inner peripheral surface, so that a certain amount of the condensate of the heated steam is dammed near the end of the inner peripheral surface. I'm trying to keep it up. On the other hand, the condensate at the center of the inner peripheral surface is
It is designed to be discharged to the outside by a suction nozzle. Therefore, the heat transfer coefficient at both ends of the drying tube is lowered by the condensate film layer, which prevents overheating and maintains a nearly uniform temperature distribution across the outer peripheral surface of the drying tube in the width direction. can do.

Furthermore, in the drying cylinder disclosed in Japanese Patent Publication No. 39-904, by attaching and removing a stopper to a hole formed in the weir, on the other hand, in the drying cylinder disclosed in Japanese Patent Application Publication No. 56-159390, A weir is constructed of two plates, each of which has a notch and can slide relative to each other, and by adjusting the overlap of the notches on each plate, the height of the weir can be changed to collect a condensate film. The layer thickness can be adjusted.

[Problem that the invention seeks to solve]

However, the conventional drying tube described above has two major drawbacks. First, the height of the weir, ie the thickness of the condensate film layer, cannot be changed during operation of the drying tube. Second, it is impossible to change the state in which condensate is collected near both ends of the inner circumferential surface of the drying cylinder to a constant thickness and is discharged from the center. As long as these drawbacks exist, it is actually impossible to uniformly heat and dry the paper material across its width. This is because the moisture profile of the paper material before it transfers to the drying tube is not necessarily the same across the width, nor is it necessarily constant, and the degree of dryness of the paper material to be made also varies depending on the paper material. This is because it changes depending on various factors such as the width of the wood, the basis weight, the speed of the paper, and the ash content.

As mentioned above, it is true that there is a general tendency for the drying tube edge to become overheated more easily than other parts, but on the other hand, the moisture profile and degree of dryness of the papermaking material, etc. It is also true that the situation is such that both conditions must be taken into consideration in order to uniformly heat and dry the papermaking material.

〔the purpose〕

Therefore, the purpose of the present invention is to make it possible to adjust the thickness of the condensate film layer accumulated inside the drying tube in various ways in the axial direction of the drying tube during operation, thereby reducing the fluctuation of the moisture profile of the papermaking material. The purpose of this invention is to quickly respond to such changes by changing the temperature distribution in the direction of the rotational axis of the drying barrel, thereby achieving uniform heating and drying across the width of the paper material.

[Means for solving problems]

According to the present invention, a horizontally arranged cylinder having a smooth heat dissipating outer circumferential surface for engaging and heating drying a belt-shaped transitional wet paper material and rotatably supported at both left and right ends provided with an end plate; A heated steam introduction path formed in the cylinder so as to communicate with the inner space of the cylinder, and a suction port opened close to the inner peripheral surface of the cylinder, for sucking up the condensate of the heated steam. and a suction amount adjustment section that changes the amount of condensate sucked up by the suction nozzle by operating from the outside of the cylinder, and communicates with the suction nozzle and with the outside of the cylinder. In the drying cylinder, an annular weir is provided along the circumferential direction on the inner circumferential surface of the cylinder to partition the inner circumferential surface of the cylinder into a plurality of parts along the rotation axis direction, and A discharge port that communicates both sides of the annular weir is formed at an appropriate position of the annular weir, and a valve body that opens and closes the discharge port by moving along the annular weir is provided, and the valve body is moved to move the valve body. means is disposed near the annular weir, the suction nozzle is disposed in one or more of the parts partitioned by the annular weir, and the valve body moving means is operated from outside the cylinder. A drying cylinder with a characteristic axial heating degree adjustment device is provided.

[Effect]

In the drying cylinder with the axial heating degree adjusting device of the present invention, the ear part of the cylinder becomes overheated, the moisture profile of the transition paper material becomes uneven,
When the paper is changed, the height of each annular weir and/or the amount of condensate sucked into the outlet pipe is changed individually from the outside of the cylinder during operation. As a result, the thickness of the condensate film layer on the inner peripheral surface of each part of the cylinder partitioned by each annular weir changes, and the axial thickness distribution of the condensate film layer formed on the inner peripheral surface of the cylinder to various distribution patterns such as uniform, upward-rightward, upward-leftward, concave, convex, and wavy. For example, when the moisture profile of the transition wet papermaking material shows a moisture content distribution that increases upward to the right, an axial thickness distribution pattern of the condensate film layer that increases upward to the left is formed in accordance with the distribution pattern. The thicker the condensate film layer, the lower its heat transfer coefficient, which suppresses the amount of heat supplied to the inner circumferential surface of parts of the cylinder that are at risk of overheating. The cylindrical part in which the parts engage will be supplied with the heat necessary for sufficient drying. The paper material is then heated and dried uniformly across its width.

〔Example〕

As shown in FIG. 1, an embodiment of a drying cylinder having a variable axial heating degree according to the present invention has a smooth heat dissipating outer circumferential surface 2 that engages and heats and dries a belt-shaped transition wet paper material p.
0, and is rotatably supported via bearings 250, 250' by rotating shafts 25, 25' at both left and right ends provided with end plates 24, 24', and a horizontally arranged cylinder 2;
The inner space 2 of the cylinder 2 passes through the rotating shaft 25 of the cylinder 2.
7, an introduction path 28 for heated steam S formed on the rotating shaft 25 of the cylinder 2 so as to communicate with 21 into five parts along the rotational axis direction, four annular weirs 22a, 22 with variable weir heights that can be individually operated from the outside of the cylinder 2.
b, 22c, 22d, and an inner peripheral surface 210a of each portion of the cylinder 2 partitioned by the annular weirs 22a to 22d.
1 and 2 suction ports 30a× opened close to 210b, 210c, 210d, and 210e, respectively;
2,30b×1,30c×2,30d×1,30
Suction nozzles 3a x 2, 3b x 1, 3c x for sucking up condensate d of heated steam S, having e x 2
2, 3d×1, 3e×2 and partial inner peripheral surface 210a
- 210e are connected to each of the suction nozzles 3a to 3e, respectively. Connecting parts 30A, 30B, 30 that can be operated individually from the outside of the cylinder 2 and are in communication with the outside of the cylinder 2 and can change the suction amount of the condensate d.
It is equipped with an outlet pipe 3 having pipes C, 30D, and 30E.

The outlet pipe 3 includes a rotary joint part 32, a header part 31, suction amount adjusting parts 4a, 4b, 4c, 4d, 4e, and a wire passage part 310, which are connected to each other. And the outlet pipe 3 is
It passes through the rotation shaft 25 and extends through the inner space 27 of the cylinder 2 along the rotation axis, and its tip is connected at one end via the end cap 312 and projects to the outside of the cylinder 2 through the rotation shaft 25'. It is supported by a wire passing portion 310, and a current collecting ring 50 is connected to a protruding portion of the wire passing portion 310. A rotary joint portion 32 is connected to a portion of the outlet pipe 3 that protrudes from the rotating shaft 25 . Connection portions 30A to 30E are inserted through and connected to each of the header portions 31 of the outlet pipe 3, and suction amount adjustment portions 4a to 4e are connected to the insertion ends of the connection portions 30A to 30E, respectively, to adjust the volume of the cylinder 2. The suction amount adjusting parts 4a to 4e communicate with the outside, and the suction amount adjusting parts 4a to 4e connect to the outlet pipe 3 through the current collecting ring 50.
By the signal sent by the signal line 41 which is connected to the suction amount adjustment parts 4a to 4c,
They can be operated individually from the outside of the cylinder 2. Therefore, the outlet pipe 3 can individually adjust the suction amount of the condensate d taken up by the suction nozzles 3a to 3e from the outside of the cylinder 2, respectively. Suction amount adjustment part 4
As a to 4e, thermoelectric valves operated in two positions by shape memory alloy springs are used in this embodiment, but for example, electromagnetic valves, various motor-driven valves such as pulse motors, bimetal type, liquid or gas expansion type, etc. Various thermoelectric valves such as the following are suitable. Any type of valve other than these types may be used. Many adjustment means are known that can be remotely controlled in various ways.

The annular weirs 22a to 22d have an annular weir body 220 with a letter-shaped axial cross-section, and the outer circumferential ends of the pair of legs 222 of the weir body 220 are closely placed on the inner circumferential surface 21 of the cylinder 2 and parallel to each other. It extends circumferentially. The annular weirs 22a to 22d each have discharge portions 6a, 6a, 6a, 6a, 6a, 6a, 6a, 6a, 6a, 6a, 6b for the condensate d, spaced apart in the circumferential direction, respectively.
A plurality of 6b, 6c, and 6d are provided. The discharge portions 6a to 6d each have a pair of discharge ports 60 facing each other in the axial direction and opening in each leg portion 222 of the weir body 220, respectively. In the annular weir 22a, the annular weir 22b, In the annular weir 22c, outlet ports 60 that are long in the circumferential direction are opened at the lowest positions of the respective legs, and in the annular weir 22d, at the lowest positions and intermediate positions of the legs. There is. The inner space of the weir body 220 has a valve chamber 62 which is partitioned on both sides in the circumferential direction by partition walls 224 so as to sandwich the discharge port 60 and is formed by opening the inner circumferential wall 226 of the weir body 220. A substantially rectangular valve body 64 that is elongated in the circumferential direction is fitted into the valve chamber 62 so as to be in sliding contact with the inner surface of the leg portion 222 and to be freely slidable in the radial direction. A movable iron core 64a constituting a valve body moving means for operating the valve body 64 is fixed and protrudes radially inward on the upper part of the valve body 64, and a fixed iron core 64b also constituting a valve body moving means. However, the lower part is connected to the inner peripheral wall 22 of the weir body 220.
The movable iron core 64a is housed in a case 640 fixed to the movable iron core 64a. A solenoid type electromagnetic coil 640b constituting a valve body moving means is fixedly wound around the fixed iron core 64b so that the movable iron core 64a is sucked into the fixed iron core 64b. From the electromagnetic coil 640b, there is a conduit (not shown), a lead-out pipe 3, and a wire passage part 310 of the cylinder 2.
A signal line 41 extends through the current collector ring 50. The movable iron core 64a is surrounded by a bellows 642.The upper end of the bellows 642 is fixed to the bottom of the case 640, and the lower end is fixed to the upper part of the valve body 64, so that the inside of the case 640 is insulated from the outside. has been done.

In the embodiment described above, the valve body 64 is slidable in the radial direction, but the valve body 64 may be slid in the circumferential direction. The valve opening formed in the weir body may be a circular hole as shown in Japanese Patent Publication No. 39-904, or a circular hole as shown in Japanese Patent Publication No. 159390-1983.
It may also be a notched hole as shown in the publication. Furthermore, the weir body and the valve body are each provided with a circular hole, a notch-shaped hole, an elongated opening, etc. as described above, and the valve body is slidable in the radial direction or the circumferential direction with respect to the weir body. Therefore, the structure may be such that the hole in the dam body and the hole in the valve body are overlapped with each other so that the discharge passage for the dam condensate is penetrated or closed. Of course, as in the above embodiment, the discharge port is opened only in the weir body, and the closed valve body is slid in the radial direction or circumferential direction with respect to the weir body, so that the condensate discharge passage is penetrated or blocked. It is also possible to have a configuration in which

The valve body moving means for sliding the valve body in the radial direction or the circumferential direction with respect to the weir body may be electromagnetic, various electric means such as a gear transmission mechanism driven by a pulse motor, bimetal, shape memory alloy spring, etc. Various types of movement means can be used, including various thermoelectric means driven by thermal expansion of liquids or gases. Many transportation means are known that can be remotely controlled in various ways.

Note that various configurations of the cylinder, suction nozzle, rotary joint, current collection ring, etc. used in the drying cylinder with the axial heating degree adjusting device according to the present invention are known, so explanations thereof will not be given here. Omitted.

In this embodiment, as described above, if the ear part of the cylinder 2 becomes overheated, the moisture profile of the transitional wet paper material p becomes uneven, or the paper is changed, the operation will be adjusted accordingly. Inside, from the outside of the cylinder 2, the heights of the annular weirs 22a to 22d and/or the amount of condensate d sucked into the outlet pipe 3 are individually controlled. In the annular weir 22a, the weir body 22
The discharge part 6a, in which the discharge port 60 is opened at the lowest position of the leg part 222 of
The discharge part 6a, which is connected in parallel to the signal line 41L passed through 0 and has a discharge port 60 opened at an intermediate position of the leg part 222, is connected in parallel to the signal line 41M, which is different from the signal line. Therefore, for example, if the signal line 41L is energized, all the discharge ports 60 (lowest position) of the discharge part 6a are fully opened and the annular weir 22
The height of a is set to 0. If only the signal line 41M is energized, all the discharge ports 60 (intermediate position) are fully opened and the weir height is set to l. Each signal line 41M, 41L
If the power is cut off, all discharge ports 60 of the discharge section 6a are closed.
is fully closed as shown in Figure 1,
The height of the weir is set to L.

Therefore, the paper material p that engages with the partial inner circumferential surface 210a
If only a portion of the annular weirs 22b to 22d is overheated and the moisture content of that portion decreases, all the outlet ports 60 (lowest positions) of the respective discharge portions 6b to 6d of the annular weirs 22b to 22d are fully opened and the annular weirs 22b to 22d are The height of the annular weir 22a is set to zero, and the height of the annular weir 22a is set to l or L by fully closing the outlet 60 (lowest position) and/or the outlet 60 (intermediate position) of the outlet part 6a of the annular weir 22a. At the same time, the suction amount adjusting section 4a is fully closed to stop the suction of the suction nozzle 3a, and the suction amount adjusting section 4b to 4
Fully open one or more of e. At this time, whether the height of the annular weir 22a is set to 1 or L is determined depending on the moisture content value (degree of overdrying) of the paper material p portion.

In this way, the condensate d that has condensed on the partial inner circumferential surface 210a is stopped by the head plate 24 and the annular weir 22a, and the high speed rotation of the cylinder 2 (circumferential speed approximately
400m/mm~1500m/mm) partial inner peripheral surface 21
A condensate film layer with a thickness of l or L is formed on 0a.
The condensate film layer suppresses the amount of heat supplied to the paper material p portion, correcting its overdrying. As for the value of the weir height l or L, l is usually determined in the range of 5 mm to 15 mm, and L is determined in the range of 5 mm to 25 mm. Also,
The condensate d that has overflowed over the annular weir 22a onto the partial inner circumferential surface 210b is transferred to the suction nozzles 3b, 3c,
The suction nozzle, which is in the open state of either 3d or 3e, passes through or does not pass through any of the annular weirs 22b to 22d and is sucked out, and is sucked out through the outlet pipe 3 that communicates with the suction nozzle. It is discharged to the outside of the cylinder 2. The distance between the suction ports of the suction nozzles 3a to 3e and the inner peripheral surfaces 210a to 210e of each part is approximately
Since it is about 1.5 mm, each part inner peripheral surface 210b~
An extremely thin condensate film layer with a thickness of about 1.5 mm is formed on 210e. The paper material p can thus be heated and dried with a uniform moisture profile and at the same time a maximum heat transfer rate.

As described above, each portion inner circumferential surface 210b-2
10e, the valve openings of the discharge parts 6b to 6d of the annular weirs 22b to 22d and/or the valve openings of the suction amount adjusting parts 4b to 4e connected to the respective connecting parts 30B to 30E of the outlet pipe 3 are individually adjusted. By operating as shown in FIG. It is possible to create a desired distribution pattern, such as uniform, upward to the right, upward to the left, concave, convex, or wavy.

In this embodiment, the inner circumferential surface 2 of each portion of the cylinder 2 is
Suction nozzles 3a to 3e for 10a to 210e
Generally, in this type of drying cylinder, the ear portion of the cylinder becomes overheated, so there is no need to provide a suction nozzle on the inner peripheral surface of the portion corresponding to the ear portion. This is because the thickness of the condensate film layer formed on the inner peripheral surface of the part must be thicker than the thickness of the condensate film layer formed on the inner peripheral surface of the central part to suppress the amount of heat supplied. Therefore, there is no need to suck up the condensate using a suction nozzle, and the thickness of the condensate film layer can be adjusted by changing the height of the annular weir in stages.

In the embodiments described above, the annular weir is provided with one or two stages of discharge parts, but it is also possible to provide three or more stages.

The suction nozzle used in the drying cylinder with variable axial heating degree according to the present invention may be a so-called rotary siphon type in which the suction nozzle rotates together with the cylinder, or a suction nozzle that is fixed and does not rotate together with the cylinder. It may be of the so-called fixed siphon type.

〔effect〕

According to the drying cylinder with variable axial heating degree of the present invention,
During the operation of the drying tube, the thickness of the condensate film layer collected inside can be adjusted in various ways in the axial direction of the drying tube. It is possible to quickly respond to and overcome various factors that impede uniform heating drying across the width of the papermaking material, such as fluctuations in the moisture profile of the papermaking material. Uniformly heated and dried.

[Brief explanation of drawings]

FIG. 1a is a side sectional view of a drying tube with an axial heating degree adjusting device according to the present invention. Figure 1b shows the first
It is a sectional view taken along the line A--I in Figure a. Figure 1c
is a sectional view taken along the Ro-Ro line in FIG. 1b. [Explanation of symbols], 2...Cylinder, 20...Outer peripheral surface,
21...Inner circumferential surface, 210a to 210e...Partial inner circumferential surface, 22a to 22d...Annular weir, 24, 24'
... End plate, 27 ... Inner cavity, 28 ... Introduction channel, 3
... Outlet pipe, 3a to 3e ... Suction nozzle, 30a
~30e... Suction port, p... Paper making material, S... Heated steam, d... Condensate.

Claims (1)

[Scope of Claims] 1. A horizontally arranged cylinder having a smooth heat dissipating outer circumferential surface in which a belt-shaped transitional wet paper material is engaged and dried by heating, and is rotatably supported at both left and right ends provided with an end plate. , having an introduction path for heated steam formed in the cylinder so as to communicate with the inner space of the cylinder, and a suction port opening close to the inner circumferential surface of the cylinder, for sucking the condensate of the heated steam. a suction nozzle for collecting liquid, and a suction amount adjustment part that changes the amount of condensate sucked by the suction nozzle by operating from the outside of the cylinder,
In a drying cylinder comprising an outlet pipe communicating with the suction nozzle and communicating with the outside of the cylinder, an annular weir that partitions the inner circumferential surface of the cylinder into a plurality of parts along the rotational axis direction is installed in the cylinder. a valve provided along the circumferential direction on the inner circumferential surface, forming a discharge port communicating both sides of the annular weir at an appropriate position of the annular weir, and opening and closing the discharge port by moving along the annular weir; a valve body moving means for moving the valve body is disposed near the annular weir, the suction nozzle is disposed in one or more of the parts partitioned by the annular weir, and the valve body is moved. A drying cylinder with an axial heating degree adjusting device, characterized in that the means is operated from outside the cylinder.