JPS595717B2 - Drying rolls in paper machines, etc. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot air roll for a papermaking machine used in a papermaking process.

In the multi-tube dryer of a paper machine, the ventilation of the tunnel-shaped part surrounded by the cylinder dryer, paper, canvas, etc., so-called pocket ventilation, has a great effect on the drying of paper.

Conventionally, ventilation in this area was done using "hot air rolls" or "hot air ducts."
It has been widely practiced.

However, with hot air rolls, the hot air is supplied from near the bearing journals at both ends of the roll, and while passing through the inside of the roll, it is sent to the outside of the roll only on the canvas-hugging surface of the roll, so that the hot air penetrates the canvas.

For this reason, the hot air flow path cannot be made large due to restrictions such as the size and structure of the roll, and requires many bends, resulting in a considerable pressure loss of the hot air within the roll.

Furthermore, in order to deal with uneven drying of paper, it is often required to control the blowing of hot air across the middle of the canvas, but for the same reason, the current situation is to divide the canvas into about three parts.

However, depending on the size of the paper machine, dividing the paper into three parts may not be effective, and a smaller division is required.

In addition, in the hot air duct method, in which hot air is sent into the pocket by passing through the highly air permeable canvas using a duct placed on the outside of the pocket using entrainment by the roll nip, etc., the canvas running speed and the air permeability of the canvas can be adjusted. The amount of hot air passing through the dryer varies greatly due to changes, etc., making it impossible to meet the demand for a constant drying effect in all cases.

In addition, to deal with uneven drying, even though the duct itself can be divided relatively easily, the hot air is not blown out because it is in close contact with the canvas. The hot air distribution changed, leading to a reduction in the ability of the penetrating hot air to respond to uneven drying.

The present invention reduces the hot air pressure loss in the hot air roll in the paper drying device used in the papermaking process, eliminates drying unevenness in the paper width direction, and reduces the hot air pressure loss due to changes in the running speed of the canvas and the air permeability of the canvas in the hot air duct system. The object of the present invention is to provide a device that reduces the amount of change.

The present invention uses a canvas roll as a cylindrical shell having a large number of through holes inside and outside, both ends of the cylindrical shell are closed and rotatably supported, and the canvas is wound around the unwrapped portion of the canvas. A hot air supply box is arranged on the outer periphery, and hot air is sent into the cylindrical shell from the outer periphery of the cylindrical shell through the hot air supply box, and then the hot air is passed through the canvas through the pores of the cylindrical shell at the part where the canvas is wrapped. The canvas roll is fed into a pocket between the cylinder dryer and the canvas roll.

In one embodiment, the cylindrical shell and the hot air supply duct are partitioned in the axial direction of the canvas roll to accommodate the distribution of hot air in the width direction of the wet paper, and each chamber of the hot air supply duct is provided with a regulating valve.

A member is fixed to the hot air supply box to close the gap between the canvas and the hot air supply box.

According to the present invention, it is possible to relatively easily divide the hot air blowing width of both the roll itself and the hot air supply box, and it is possible to deal with uneven drying of paper.

In addition, the flow paths in the hot air supply box and the roll are relatively unrestricted, which can overcome the disadvantage of having to pass through the small holes in the cylindrical shell of the roll twice.

The hot air is reliably sent into the pocket through the small holes in the roll, and at the same time, the hot air leaking from the seal between the hot air supply box and the roll is further sealed by the seal between the hot air supply box and the canvas.

Therefore, the hot air during this period is supplied to the pocket by the same function as the hot air duct system in the case of high air permeability canvas.

This is designed to overcome the disadvantages of conventional hot air rolls, where the air flowing as the canvas travels enters the pocket due to the roll nip, and the hot air supplied into the pocket escapes. .

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing a part of a multi-tube drying device of a paper making machine.

A plurality of cylinder dryers 1, 1 are arranged in parallel and in a staggered manner in two upper and lower stages. Wet paper paper 2 is alternately wound around the upper group and the lower group, and an endless dryer is placed over the cylinder dryers 1, 1. For example, canvases 3.3 made of felt are stacked, and the canvases 3.3 are connected to cylinder dryers 1, 1, 1,
It is wound around canvas rolls 4, 4 arranged between ... and dehydrated and dried there.

FIG. 2 is a side view of a drying device equipped with the drying roll of the present invention, showing an enlarged view of the upper canvas roll 4 in FIG. 1, and FIG. 3 is a cross-sectional view taken along line AA in FIG. .

The cylindrical shell 5 has a large number of small holes running through the inside and outside of the cylinder over the width of the paper making, and a short shaft 7 is fixed to both ends via an end plate 6, and the short shaft 7 is fitted with a sealed bearing. It is supported by bearings 9 in box 8 (bearing box 8
(detailed explanation is omitted).

A hot air supply box 11 covers the outer periphery of the cylindrical shell 5 from above so that the hot air supply box 11 is between the canvases 3 wrapped around the cylindrical shell 5, and the cylindrical shell is placed on the edge of the hot air supply box 110 50 Seal members 12 and 13 with grooves that produce a labyrinth effect in the circumferential direction and the generatrix direction are fixedly disposed on the hot air supply box 11.

The inside of the cylindrical shell 5 is divided into a plurality of chambers by a partition plate 14, and the hot air supply box 11 is provided with a partition plate 15 at the same position as the partition plate 14.
The ends of the partition plate 15, like the side plates of the hot air supply box 110, are provided with the same sealing material 10 as the sealing material 13 to prevent the movement of hot air between them and the cylindrical shell 5, respectively.

A hot air header 16 into which hot air supplied from a hot air supply port 17 is blown is fixed above the hot air supply box 11, and a hot air header 16 is fixed to each chamber of the hot air supply box 11 so as to be rotatable around a shaft 18. The opening degree is adjusted by an artificial damper 19 so that hot air is sent from the hot air header 16.

A sealing material 21 is fixed to the hot air supply box 11 so as to be close to the canvas 3 wrapped around the cylinder dryer 1.

The cylinder dryer 1 rotates in the direction of the arrow shown in FIG.

The wet paper web 2 is alternately moved between the upper and lower cylinder dryers 10, and is brought into pressure contact with the canvas 3 and the cylinder dryer 1 to be dried.

The hot air is supplied from the hot air supply port 17 to the hot air header 16 while being maintained at a predetermined pressure and temperature.

The artificial damper 19 of each section connected to the hot air supply box 11 from the hot air header 16 is adjusted according to the required hot air distribution, and the air volume according to the distribution is adjusted to the hot air supply box 1.
1, enters into the cylindrical shell 5 through the small hole of the cylindrical shell 5 of the canvas roll 4, and further enters the small of the cylindrical shell 5 from the surface of the cylindrical shell 5 held by the canvas 3. It passes through the hole again and penetrates the canvas 3 outside the cylindrical shell 5.

The hot air leaking from the sealing material 12 and 13 between the hot air supply box 11 and the surface of the cylindrical shell 5 enters the saving B made up of the hot air supply box 11, the canvas 3, and the sealing material 21, and is transferred to the cylindrical shell 5. Penetrates through the canvas 3 due to the high air permeability of the nipped canvas 3.

The hot air that has passed through the canvas 3 enters the saving pocket (C) shown in FIG. 1 between the cylinder dryer 1, the wet paper 2 wrapped around it, and the canvas 3 wrapped around the canvas roll 4.
Furthermore, the hot air acts on the wet paper 2 to dry it.

As described above, the present invention makes it possible to control the air volume distribution by subdividing the hot air blowing width, and in the case of a wide width paper machine, etc., it can be controlled according to the condition of uneven drying.

Therefore, the ability to deal with uneven drying was improved.

It also has the function of reliably supplying hot air into pockets, which is an advantage of hot air rolls.

In addition, the required hot air supply pressure can be equal to or lower than that of the conventional method.

Because of this, an efficient drying effect can be obtained with a minimum amount of power.

Moreover, the structure of the canvas roll as a movable part is simplified, and the occurrence of failures is reduced.

And since all the hot air sealing material is located outside the canvas roll, inspection and replacement of the sealing material is easy.

[Brief explanation of the drawing]

Figure 1 is a partial side view of the drying equipment used in the papermaking process, Figure 2
The figure is a side cross-sectional view of the embodiment of the present invention, and FIG. 3 is A--A in FIG.
It is an A sectional view. 1... Cylinder dryer, 2... Wet paper, 3... Canvas, 4... Canvas roll, 5... Cylindrical shell, 6...°... End plate, 7... Short shaft, 8... Bearing box, 9... Bearing, 11... Hot air supply box, 12.13... Seal material, 14...
・Partition plate, 15... Seal material, 16...
・Hot air header, 17... Hot air supply port, 18.
...Shaft, 19...Inlet damper, 21...
...Sealing material.

Claims (1)

[Scope of Claims] 1. A cylindrical shell in which a large number of pores penetrating the canvas roll inside and out are provided around the entire circumference between the paper widths, and both ends of the shell are closed and rotatable, and the canvas is wound on the canvas roll. In a drying roll of a paper machine, etc., in which a hot air supply box is installed close to the canvas roll in the width direction of the canvas on the outer peripheral surface that is not hung, a sealing material is fixed to the hot air supply box over the entire width of the canvas and close to the canvas. A drying roll for a paper machine, etc., characterized by: 2. A partition plate is provided in the axial direction of the cylindrical shell so that the inside of the cylindrical shell is divided into several parts in the width direction of the canvas, and a hot air supply box is also installed by the partition plate at a position corresponding to the partition plate inside the cylindrical shell. A drying roll for a paper machine or the like according to claim 1, which has a similarly divided structure and can partially control the air volume distribution of hot air passing through the canvas in the width direction. 3. The paper machine, etc. according to claim 2, wherein each section divided by the partition plate of the hot air supply box has a hot air inlet, and the inlet is provided with a valve for controlling the amount of hot air, etc. Drying roll○