GB1576245A

GB1576245A - Liquid seals for high pressure steamers

Info

Publication number: GB1576245A
Application number: GB2653077A
Authority: GB
Original assignee: Sando Iron Works Co Ltd
Current assignee: Sando Iron Works Co Ltd
Priority date: 1976-06-25
Filing date: 1977-06-24
Publication date: 1980-10-01
Also published as: DE2728646B2; DE2728646C3; JPS532677A; DE2728646A1

Description

(54) LIQUID SEALS FOR HIGH PRESSURE STEAMERS (71) We, SANDO IRON WORKS CO.

LTD., a Japanese Company, of No. 4-4-5, Usu, Wakayama-shi, Wakayama-ken, Japan, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to method of sealing openings to high-pressure steamers, using a roll-seal device and a liquid, such that textile products may be fed continuous ly through the seal when the steamer is pressurised.

Textile products are often treated in high-pressure steamers, by subjecting the products to conditions of high temperature and pressure, usually in a saturated vapour, or in a high-humidity atmosphere. The Applicants have developed various forms of seal devices for steamers in which textile products are treated, which seal devices allow the continuous feeding of the textile goods into and out of the steamer whilst the interior of the steamer is pressurised.

Most of the seal devices employ a form of roll seal, in which a pair of rubber seal rolls define a nip through which the products pass when the rolls are rotated, the rolls themselves being sealed to the steamer body for instance by flexibly resilient plates. To isolate the rolls from the atmosphere within the steamer, the Applicants have developed a seal device which incorporates a U-shaped sump which contains liquid. The space between the roll seal and the sump is pressurised to the same extent as the interior of the steamer, so as to maintain a pressure balance on the liquid in the two limbs of the U-shaped sump, thereby maintaining the liquid levels constant in the sump.This, through effective at sealing the atmosphere of the steamer, requires complex equipment to maintain the pressure balance, and any leakage through the seal is of the air pressurised into the space between the sump and the roll seal. Should the balance be lost, the rolls can be exposed to the atmosphere of the steamer, and destroyed, or their life at least shortened.

Moreover, an over-pressure in said space will cause the liquid to be discharged into the steamer body, ruining the textile cloth being treated.

To prolong the life of the seal rolls, it is also usually necessary to provide a cooling arrangement therefor, such as a tank in which the rolls are partially immersed. This leads to further complications, and increases the bulk of the seal device.

It is a principal aim of this invention to provide a method of sealing an opening to a steamer, in which the apparatus used does not suffer from the disadvantages mentioned above in relation to the known form of seal device.

Accordingly, this invention provides a method of sealing an opening to a high pressure steamer, there being a chamber defining a U-shaped passage being mounted over the opening and the entrance to the passage remote from the opening being closed by a roll seal defining a nip through which products may be continuously fed, in which method the U-shaped passage is at least partially filled with liquid and on pressurising the steamer body the liquid is forced into contact with the roll seal by virtue of the internal pressure in the steamer body, whereby the liquid substantially seals the roll seal from the internal atmosphere of the steamers.

In performing the method of this invention, liquid contained within the seal device is forced toward the seal rolls (usually of rubber) by virtue of the internal pressure in the drum body of a steamer, whereby the liquid seals the clearances formed between said mutually contacting seal rolls as well as between said seal rubber rolls and the chamber of the seal. The method thus makes use of the fact that liquid is superior to air in sealing in an air-tight manner. The liquid also may serve as a lubricant, and moreover may assist cooling of the rolls.

The seal rolls are also isolated from the internal atmosphere of the steamer.

Any outward leakage of liquid may be made good by introducing further liquid into the chamber, preferably in the region of the roll seal, under a pressure greater than that prevailing within the steamer body.

Slight leakage can in fact be advantageous, firstly because it can assist the lubricating action of the liquid and secondly because the replenishment of leaked liquid by relatively cool liquid helps to maintain low the temperature of liquid contained in the chamber.

If the temperature of the liquid rises too much, because of the internal temperature prevailing within the steamer body, some liquid may be withdrawn from the chamber to be replaced by cool liquid introduced into the chamber under the pressure greater than that prevailing within the steamer body.

According to another aspect of this invention, there is provided a seal device for performing the method of this invention described above, which device comprises a chamber for mounting on a steamer body and defining a U-shaped passage for textile goods to be transferred into or out of the steamer body when pressurised, a pair of rolls rotatably mounted and sealed to the chamber such that the rolls define a nip seal over the entrance to the passage remote from the opening to the steamer body, the rolls being disposed higher than the bottom of the U-shaped passage, guide rolls for the textile goods to guide the textile goods through the passage from (or to) the seal rolls to (or from) the opening to the steamer body, a pair of rolls rotatably mounted over the opening to the steamer body and means to introduce liquid under pressure into the passage such that when the steamer is pressurised, the internal pressure acting on liquid introduced into the U-shaped passage forces the liquid upwardly into contact with the seal rolls.

By way of example only, two specific embodiments of this invention will now be described, reference being made to the accompanying drawings, in which: Figure 1 is a longitudinal sectional view through a known form of roll seal device including a liquid seal tank, showing the arrangement of the important parts thereof; Figure 2 is a longitudinal sectional view through a first embodiment of roll seal device according to this invention; and Figure 3 is a longitudinal sectional view through a second embodiment of seal device according to this invention.

Figure 1 shows a known form of seal device for a high-pressure, high temperatue steamer, utilising seal rolls defining a nip to allow the continuous introduction of textile goods into (or out of) the steamer body. The textile goods (such as cloth) pass through the roll nip into a pressurised chamber, before passing through a sump 1 containing liquid, and then entering the steamer body.

To maintain the required liquid level 2 in the sump 1, the pressure in the chamber between the sump 1 and the rolls must carefully be balanced with that in the steamer body. In this way the roll seal can be isolated by the liquid in the sump from the atmosphere in the steamer body.

Thus, in known seal device, pressure detectors have to be provided so as to enable the pressure balance to be maintained. This leads to considerable cost and complication, taking into account the temperatures prevailing in the steamer body. To lengthen the life of the rubber rolls, it is also necessary usually to arrange some cooling therefor, usually by at least partially immersing the rolls in water. This also increases the complexity and physical size of the seal device.

In Figure 2, there is shown part of a drum body 3 of a high pressure steamer, there being an inlet opening 4 in the body 3 which is sealed by a seal device 5. This seal device comprises a chamber 7, the inner part of which is shaped to define a double-folded (or zig-zag) passage 6 for textile goods to be treated in the steamer. Over the upper, inlet opening to the passage 6 for textile goods 13 are mounted a pair of mutually contacting rubber seal rolls 8 and 8' as well as a pair of flexibly resilient plates 9 and 9', respectively for closing the clearance between the rubber seal rolls 8 and 8' and the walls of the chamber 7. The plates 9 and 9' are adapted to bear on the rolls 8 and 8', over the parts thereof subjected to the internal pressure of the steamer, and thus below the nip defined by the rolls. At the outlet opening from the passage 6, through which the textile goods 13 are discharged into the steamer, there is disposed a pair of rolls 10 and 10', with a narrow gap therebetween. Guide rolls 11 for the textile goods are suitably arranged within the passage 6 to feed the cloth therealong and there being a pair of squeeze rolls 12 for pinching both surfaces of textile goods 13. A weight 17 is hung on a lever associated with the squeeze rolls 12 to allow adjustment of the pinch force.

A tubular duct 14 is positioned within the upper opening in the chamber 7, through which the textile goods pass after being carried through the rolls 8 and 8', the duct tapering towards the roll nip. Liquid supply pipes 15 are arranged to allow liquid to be introduced to the spaces between the duct 14 and the of chamber 7 defining the inlet opening, the liquid being pressurised to a pressure higher than the internal pressure of the steamer. End surface sealing plates 16 are positioned so as to contact the end surfaces of the rubber seal rolls 8 and 8' as well as the flexibly resilient plates 9 and 9', to seal these to the chamber 7. Valved exhaust pipes 18 are provided leading from the interior of the chamber 7.

The above-described apparatus operates as follows.

In the first place, water or some other required solution (for instance, a caustic solution at room temperature ) is run into the U-shaped section 6' of the passage 6 from the liquid supplying pipes 15, before the internal pressure of the drum body is raised. Then, in the case of the treatment of most textile goods, the internal pressure of the steamer body is set at about 5.5 kg/cm2 and more than 1600C. Due to the increase in internal pressure within the steamer, acting on the liquid in the U-shaped section 6' of the passage 6, the liquid is forced to flow towards the rubber seal rolls to fill up to the opening into the passage 6 closed by the rubber seal rolls. This brings about an effective seal against leakage of the internal atmosphere of the steamer.A portion of the liquid forced up to the opening may leak to a small extent through clearances between the rubber seal rolls as well as between the rubber seal rolls and the frame, but such a small leakage of liquid can serve favourably as a lubricating agent. Any shortage of liquid caused by leakage can be replenished by pressurised liquid, fed at a higher pressure than that prevailing within the steamer through the pressurised liquid supplying pipes 15. Furthermore, since the rubber seal rolls are in contact with the liquid, cooling of the rubber seal rolls will occur - especially if the temperature of the liquid is maln- tained at room temperature. or lower.

The arrangement of Figure 3 is generally similar to that described above with reference to Figure 2, and like parts are given like reference characters. The common features will not be described again. In the embodiment of Figure 3, a liquid sealing action is ac!lieved with a comparatively small quantity of liquid by appropriate shaping of the chamber 7, and the portion 6' of the :1assage 6. However, as before, when the interior of the steamer body is pressurised after introducing liquid through pipes 15, the liquid is forced into contact with the rolls 8 and 8', to effect a liquid seal there against as well as to effect cooling of the rubber rolls.

Since the quantity of liquid was used for the liquid sealing action in this embodiment is relatively small, there is a tendency for the temperature of the liquid to be raised along with the temperature within the steamer body. If this occurs, heated liquid can be discharged out of exhaust pipes 16, and further cooled liquid introduced through pipes 15. Liquid can in this way be constantly circulated so as to achieve a cooling as well as cleaning action for the rubber seal rolls simultaneously with the sealing action thereof.

As will be understood from the foregoing, a seal device of this invention, in which rubber seal rolls are subjected to a liquid for enhancing the sealing action, can give an excellent seal as compared with known seals in which rolls are only in contact with air.

Furthermore, in the above examples, cooling of the rubber seal rolls also occurs by virtue of the liquid contacting the rubber seal rolls, thereby extending durability of the rubber seal rolls.

The seal devices described above are intended for use as inlet seals to allow the introduction of textile goods into a steamer body. However, similar seal devices may of course be positioned over the outlet openings from steamers to allow the removal of textile goods from the body.

WHAT WE CLAIM IS: 1. A method of sealing an opening to a high pressure steamer, there being a chamber defining a U-shaped passage being mounted over the opening and the entrance to the passage remote from the opening being closed by a roll seal defining a nip through which products may be continuously fed, in which method the U-shaped passage is at least partially filled with liquid and on pressurising the steamer body the liquid is forced into contact with the roll seal by virtue of the internal pressure in the steamer body, whereby the liquid substantially seals the roll seal from the internal atmosphere of the steamer.

2. A method according to claim 1, in which any outward leakage of the liquid is made good by introducing further liquid into the chamber in the region of the roll seal, under a pressure greater than that prevailing within the steamer body.

3. A method according to claim 1 or claim 2, in which liquid is withdrawn from the chamber as the temperature thereof rises, and is replaced by cool liquid introduced into the chamber under a pressure greater than that prevailing within the steamer body.

4. A method according to claim 1 and substantially as hereinbefore described, with reference to Figure 2 or Figure 3 of the accomanying drawings.

5. A seal device for performing the method of claim 1, which device comprises a chamber for mounting on a steamer body and defining a U-shaped passage for textile goods to be transferred into or out of the

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Claims

**WARNING** start of CLMS field may overlap end of DESC **.

14 and the of chamber 7 defining the inlet opening, the liquid being pressurised to a pressure higher than the internal pressure of the steamer. End surface sealing plates 16 are positioned so as to contact the end surfaces of the rubber seal rolls 8 and 8' as well as the flexibly resilient plates 9 and 9', to seal these to the chamber 7. Valved exhaust pipes 18 are provided leading from the interior of the chamber 7.

The above-described apparatus operates as follows.

In the first place, water or some other required solution (for instance, a caustic solution at room temperature ) is run into the U-shaped section 6' of the passage 6 from the liquid supplying pipes 15, before the internal pressure of the drum body is raised. Then, in the case of the treatment of most textile goods, the internal pressure of the steamer body is set at about 5.5 kg/cm2 and more than 1600C. Due to the increase in internal pressure within the steamer, acting on the liquid in the U-shaped section 6' of the passage 6, the liquid is forced to flow towards the rubber seal rolls to fill up to the opening into the passage 6 closed by the rubber seal rolls. This brings about an effective seal against leakage of the internal atmosphere of the steamer.A portion of the liquid forced up to the opening may leak to a small extent through clearances between the rubber seal rolls as well as between the rubber seal rolls and the frame, but such a small leakage of liquid can serve favourably as a lubricating agent. Any shortage of liquid caused by leakage can be replenished by pressurised liquid, fed at a higher pressure than that prevailing within the steamer through the pressurised liquid supplying pipes 15. Furthermore, since the rubber seal rolls are in contact with the liquid, cooling of the rubber seal rolls will occur - especially if the temperature of the liquid is maln- tained at room temperature. or lower.

The arrangement of Figure 3 is generally similar to that described above with reference to Figure 2, and like parts are given like reference characters. The common features will not be described again. In the embodiment of Figure 3, a liquid sealing action is ac!lieved with a comparatively small quantity of liquid by appropriate shaping of the chamber 7, and the portion 6' of the :1assage 6. However, as before, when the interior of the steamer body is pressurised after introducing liquid through pipes 15, the liquid is forced into contact with the rolls 8 and 8', to effect a liquid seal there against as well as to effect cooling of the rubber rolls.

Since the quantity of liquid was used for the liquid sealing action in this embodiment is relatively small, there is a tendency for the temperature of the liquid to be raised along with the temperature within the steamer body. If this occurs, heated liquid can be discharged out of exhaust pipes 16, and further cooled liquid introduced through pipes 15. Liquid can in this way be constantly circulated so as to achieve a cooling as well as cleaning action for the rubber seal rolls simultaneously with the sealing action thereof.

As will be understood from the foregoing, a seal device of this invention, in which rubber seal rolls are subjected to a liquid for enhancing the sealing action, can give an excellent seal as compared with known seals in which rolls are only in contact with air.

Furthermore, in the above examples, cooling of the rubber seal rolls also occurs by virtue of the liquid contacting the rubber seal rolls, thereby extending durability of the rubber seal rolls.

The seal devices described above are intended for use as inlet seals to allow the introduction of textile goods into a steamer body. However, similar seal devices may of course be positioned over the outlet openings from steamers to allow the removal of textile goods from the body.

WHAT WE CLAIM IS: 1. A method of sealing an opening to a high pressure steamer, there being a chamber defining a U-shaped passage being mounted over the opening and the entrance to the passage remote from the opening being closed by a roll seal defining a nip through which products may be continuously fed, in which method the U-shaped passage is at least partially filled with liquid and on pressurising the steamer body the liquid is forced into contact with the roll seal by virtue of the internal pressure in the steamer body, whereby the liquid substantially seals the roll seal from the internal atmosphere of the steamer.
2. A method according to claim 1, in which any outward leakage of the liquid is made good by introducing further liquid into the chamber in the region of the roll seal, under a pressure greater than that prevailing within the steamer body.
3. A method according to claim 1 or claim 2, in which liquid is withdrawn from the chamber as the temperature thereof rises, and is replaced by cool liquid introduced into the chamber under a pressure greater than that prevailing within the steamer body.
4. A method according to claim 1 and substantially as hereinbefore described, with reference to Figure 2 or Figure 3 of the accomanying drawings.
5. A seal device for performing the method of claim 1, which device comprises a chamber for mounting on a steamer body and defining a U-shaped passage for textile goods to be transferred into or out of the

steamer body when pressurised, a pair of rolls rotatably mounied and sealed co the chamber such that the rolls define a nip seal over the entrance to the passage remote from the opening to the steamer body, the rolls being disposed higher than the bottom of the U-shaped passage, guide rolls for the textile goods to guide the textile goods through the passage from (or to) the seal rolls to (or from) the opening to the steamer body a pair of rolls rotatably mounted over the opening of the steamer body, and means to introduce liquid under pressure into the passage such that when the steamer is pressurised, the internal pressure acting on liquid introduced into the U-shaped passage forces the liquid upwardly into contact with the seal rolls.
6. A seal device according to claim 5 and substantially as hereinbefore described with reference to and as illustrated in Figure 2 or in Figure 3 of the accompanying drawings.