FI117400B - Paper:making machine steam blower box - has removable perforated steam outlet plate for cleaning - Google Patents

Abstract

The steam blower box, to deliver steam to a paper web to be passed through a water extraction press section of a papermaking machine, has a removal steam outlet plate (22). A perforated plate insert (20), where the steam flows through, is at each zone chamber (3), and can be removed, or a common removable plate (22) can be fitted to and removed from the assembly for all the zone chambers (3). At least one perforated plate insert, and pref. each one, has its own steam outlet plate attached to it. The steam outlet plates (22) are structured to deliver steam against the web, against its direction of travel by a suitable angle. The steam outlet plates (22) and the web form a steam chamber between them in a wedge-shaped cross section, with the wedge point against the direction of web travel.

Description

1 1 7400 Steam blasting box

The invention relates to a steam blowing box for applying steam to a moving material web, e.g. to a paper web to be dried and passing through a press section of a papermaking machine. Reference is made to DE 41 25 062 Ai.

Such a steam blasting box is mainly used in papermaking. Its purpose is to increase the temperature of the material web by means of steam introduced into the material web 10 to increase the drying efficiency of the press section. The steam blasting box then offers the possibility of influencing the moisture transverse profile of the material web by using a different sectional steam import function · 15

In a known design, the steam exiting the compartment chambers (or * zone chambers ") is controlled by valves located inside the steam blasting box. Each repair zone is provided with a separate valve, usually a pneumatic control.

One disadvantage is that the steam blast box zone · *** * i \\ chamber contamination {mm. caused by fiber particles

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infiltration) in known structures can be reduced by t · * ·:; \\ * 25 only with great use of time and cost.

It is an object of the present invention to provide a device of the type described above, whereby the cleaning and maintenance of the steam blowing box is minimized. at a cost like hitherto.

:: ': 30 ···· According to the invention, the problem is solved by the features of claim 1. Accordingly, the steam blasting plate: '·. !!!: the steam plate and - if any - the perforated plate pellets placed in the zone chambers have been made to be dismantled for better cleaning • * ·'; *: * *: 3 5 because of the opportunity.

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In a preferred embodiment of the invention, the following is provided: 117400 2 Steam is supplied from the main steam line to a steam distributor mounted outside the paper machine, preferably adjacent to the paper machine, e.g. easy access to category 5. This steam distribution device is equipped with individual heating elements (control valves). A mounting plate fixedly fixed to the steam blasting box The flexible wires between the plate and the adjustment valves receive the shaking movements and compensate for the steam distribution in the 15 boxes possible heat elongation · The valve drive is controlled by an electric motor.

The invention will now be described, by means of a preferred embodiment, together with the accompanying drawings:

Figure 1 overall view; 4 * 'i ···> ·

Figure 2 is a cross-sectional view of a steam blast box; •

Fig. 3 a zone chamber having a perforated plate insert; :; Λ: • «a aa · a · · a • a a ·

Fig. 4 is a cross-section of '30 • a · 9e t other than that of Fig. 2

Fig. 5 is a perforated plate insert in Fig. 4.

··· **, * «* · e The steam blasting box 48 consists of a self-supporting stainless steel * * * # * * 1 * e" structure; it extends across the roll direction of the paper web P: J 35, # 35 transverse to the direction of travel of the paper machine. *! ·! * through the front side FS to the drive side TS. 1 shows only the steam blow box drive-side end of Fig. Alatukikehykseen 1, 1 'are welded to the strips 43, which has 117 400 3 the bores 10 and 11 Alatukikehys 1, 1' and ylätukikehys 2 are connected to each other sidewalls 8 and 9. This design provides optimum transverse stability · Supporting frames 1, 1 'and 2, and sidewalls 8 and 9 delimit the central chamber 5 15 for feeding to the passing paper web P.

Steam conduit 13 opens into lower chamber 12. As shown in FIG. 1 10, the preheating steam ("steam II") flowing therein enters through chamber 10 and 14 into chamber 15 which surrounds the tube bundle 4. 4, the inlet steam II 15 is first passed through the chamber 12 from the service side to the treatment side and then enters the chamber 15. This steam II, having a temperature higher than that of the steam I compartment steam line 4, also ensures that the valves are closed and the individual zone chambers 3 do not cool. Thanks to this, e.g. the fact that no steam condensate * and no or no condensation is formed in the zone chambers .. :: 5 .: little condensation. Otherwise, steam I and steam: *; *: *; Il strict separation.

The individual zone chambers 3 are located on the lower support frame • 1, 1 '. They are secured by the side plates 19 and 17.

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A separate steam line 4 always opens into the zone chambers.

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. Each zone chamber includes a perforated plate insert 20 having • * · ** perforated plates 34 having a free cross-sectional area increasing by '• f · * * 30 per steam removal. These perforated plates 34 effect that the vapor I contained in the individual zones is uniformly distributed over the width of the zone. Individual perforated plate •. · * ·. *. the bags 20 may be withdrawn for maintenance (Fig. 3).

*. * 35 The individual zone chambers 3 are limited by a common vapor evacuation plate 22 (Fig. 1). This is screwed onto the plate members 19 and 1, or secured by guide strips 44 so that it can be disassembled without any problem for cleaning. It has a plurality of 117400 rows of blowing openings 32 arranged in succession 4 longitudinally · As shown in Figures 4 and 5, each of its perforated sheeting bags 20 'has its own vapor extraction plate 22' the steam I flows against the incoming web. Everywhere where steam condensation could occur, outlet openings 11, 18 with associated gutters 24, 25, 26, 27 have been made.

10 the steam blow box 48 rest on the drive side of Figure 1, the mounting plate 28, which may be e.g. alatukike-frame in 1, 1 'extension (Fig 2), via the portable stand 51 on. Steam lines 4 are extended against the direction of flow of steam over the drive end 15 of the steam blasting box; their inlet ends are attached, for example, to the mounting plate 28. In total, the adjusting member marked R is disposed laterally outside the paper machine and comprises, for each zone chamber 3, a control valve 35 actuated by a stepper motor M. ! Γ at least partially formed as flexible conductors.

The outflow ends 29 'of the flexible conduits are fixed as follows: * jV; called service board 30. This service board 30 is connected; ; V: with quick-release clips 31 to mounting plate 28. These quick-release clamps allow fast steam discharge when disassembling the steam blasting box. ** y. disconnection possible. The control valves 35 are designed so that they can be assembled into the steam distribution channel 36 by · · * t *. several side by side. Each of the steam distribution channels 36 is fed with • * «” · * steam from the main steam line H.

* .tS * 30. ·· * \ ώ **: The removable vapor extraction plate 22 has, as already mentioned, a number of longitudinal blades ··· *. 32 rows of spears. The direction of deburring is opposite to that of the paper *. / ** '* · · * * and skewed. As a result, ******* * * · * 35 provides a better mixing of the vapor with the retracted air boundary layer, which increases the effect of steam condensation on the surface of the paper web.

Claims (6)

117400 5 A vapor blowing tray for introducing steam into a web of material, e.g., a paper web to be dried and passing through a press section of a papermaking machine, with the following 5 features: the vapor blowing box extends transversely across the web; the steam blasting box has a plurality of zone chambers (3) arranged side by side in a row over the width of the web and covered by a tear off steam evacuation plate (22); each zone chamber is connected to a steam source via its own control valve (35); characterized in that the vapor removal plate (22) is removable; and that the arrangement of the vapor discharge plate (22, 22 ') is such that the outlet direction is oblique to and opposite to the direction of travel of the web. Steam degasser according to Claim 1, characterized in that each zone chamber (3) is provided with a removable perforated plate insert (20) through which the steam flows. i 9 j «i1 A vapor extraction box according to claim 1 or 2, characterized in that a plurality of zone chambers (3) have a common removable vapor extraction plate (22). ·; · # 1 • ♦ · A vapor evacuation shoulder according to claim 2, characterized in that at least one perforated plate perimeter (20 '), preferably each perforated plate perimeter, has a vapor extraction plate (22') attached thereto. • .5 "• · .1: ·? · T ···. The vapor according to any one of claims 1 to 4, which is characterized in that the vapor discharge plate (22; 22 ') - *: · 1: 1 limits the evaporation chamber with the web passage · ♦ ·:: 35 117400 6 Vapor extraction box according to Claim 5, characterized in that the evaporation chamber, as seen in cross-section, is wedge-shaped with the tip of the wedge opposite to the direction of travel of the web. 5