FI68108C - TILLSLUTSVENTIL FOER ROEKGASKANALER EL DYL - Google Patents

Description

1 68108

Shut-off valve for flue gas ducts etc.

Today, single- or multi-slat dampers are generally used as closing elements for gas ducts. The disadvantage of these is that the tightness in the closed position is insufficient.

Leaks occur especially at the ends of the flaps; a relatively wide gap must be left between the ends of the dampers and the wall of the duct so that the dampers, when in the open position, do not get caught by the soot and ash accumulating in the gap. In practice, however, the dampers are often almost stuck, making it very difficult to turn them to the closed position. In addition, the scaling of the dampers and the settling ash cause leaks in the barrier surfaces between the dampers themselves.

15 Finnish patent publication No. 29 416 again is known another type of check valve, wherein sulkueli-shifter is a dome-like valve plate which, through an articulating spindle is pivotable wall of the duct from an adjacent position to the position in which it obliquely closes the 20 channels, the valve disc of the convex side is turned against the flow of flue gas . This shut-off valve works well per se, but as a whole is relatively complex in construction and requires carefully dimensioned sealing fittings, which makes it so expensive that it is most often satisfied with the inverted dampers mentioned at the beginning, despite their drawbacks.

The object is to provide a new shut-off valve which is simple in construction, easy to use and at the same time provides good tightness in the closed position, using the general shut-off method disclosed in Patent Publication No. 29,416.

The invention thus relates to a shut-off valve for flue gas ducts or the like, comprising an axially pivotable shut-off member, the second axial wall of the passage having a recess for receiving the shut-off member when the valve is open.

2 68108

The invention is characterized in that the axis of the closure member is hollow, in which a pivot shaft with eccentric members supporting the axis of the closure member mounted on the wall of the channel is arranged inside it. then the pivot shaft with eccentric members can be moved in a manner known per se in the longitudinal direction of the channel, and that the walls of the channel have members known per se against which the edge portions of the closing member press when the closing member moves in the longitudinal direction of the channel.

The invention will be explained in more detail below with reference to the accompanying schematic drawing.

Figure 1 shows a longitudinal section of a flue gas duct with shut-off valves.

Figure 2 shows a section along the line II-II in Figure 1.

Flue gas ducts or the like, preferably of rectangular cross-section, are indicated by reference numeral 1. The closing member of the valve is a curved damper 2, the ends of which are fixed to the hollow shaft 4, for example by means of sector-shaped plates 3. which supports the shaft 4 from the inside by means of eccentric plates 10 and the bearing 11 of which is fixedly supported on the walls 1c and 1d of the channel. A recess 5 is formed in the second wall 1a of the channel 1 in the direction of the axis 4 to receive the closing member 2 when the channel 1 is kept open. The lower part of the recess-30 may have a stop pin 6, alternatively the locking of the shaft 4 can be used in one way or another. The open position of the valve is indicated in Figure 1 by broken lines.

The closed position of the valve is shown in Figure 1 by 35 solid lines. The closing member 2 then extends over the channel 1 and its edge portions in a plane perpendicular to Fig. 1 can rest on the surface 5a, 3 681 08 of the recess 5 bounding the channel wall 1a and on the support surface 8 of the notch 7 formed in the opposite wall 1b.

The closing member is pivoted by means of a lever 13 from the recess 5 over the channel 1 on the fixed eccentrics 10 connected to the pivot shaft 9, after which the shaft 9 is pivoted from the lever 12 to the position shown in Fig. 2, the eccentrics 10 rotating against the projecting flanges 19. Corresponding flanges 10 can also be made in the walls 1a and 1b to coat the support surfaces 5a and 8.

In order to seal the openings in the walls 1c and 1d for the shaft 4, flanges 14 are formed in the shaft 4, which also control the axial movement of the closing member, and sealing rings 15 are placed outside the flanges 14, which at the same time rest on the edge of the wall opening. The seals 15 can preferably be so-called braid seals and flexible rings 16 with an outer conical collar 17 attached to the support members 18 are used to compress them into place.

To facilitate the pivoting of the closing member 2, a counterweight 20 can be attached to the shaft 4. Its attachment arms 21 are preferably dimensioned so that when the valve is open, the counterweight is fixed to the wall 1b, into which a receiving recess 25 can also be made.

The eccentrics 10 of the shaft 9 are dimensioned, for example, so that the legal point of movement has not yet been reached when the closing member 2 hits the supports 19. The lever 12 can be connected to the piston rod of a hydraulic or pneumatic cylinder 30, whereby locking in each position Of course, it is also conceivable to turn the lever 12 by hand and some suitable mechanical locking via the lever.

35 In addition to the shut-off valve according to the invention reliably closing the channel 1 and being easy to use.

4 681 08 it is also more advantageous than the current shut-off valves in that when the shut-off member 2 is in the open position it does not restrict the gas flow at all, because the shut-off member is in the recess 5 as a whole and the space required by the shaft 4 2 being in it.

The shaft 4 is preferably placed according to the drawing at the center of the circular arc of the closing member 2, but this 10 is not necessary per se. Also, the shape of the closure member does not necessarily have to be part of the jacket surface of the cylinder, but the implementation according to the drawing is the simplest in terms of forming the notches 7.

The radius of curvature R of the closing member 2 should preferably be so large, about 0.75 x the diameter C of the channel 1, that the closing member leaves the "actual" channel completely when the valve is open, as shown in Fig. 1. On the other hand, there is no reason to increase the radius of curvature R very much, since the bulge 20, i.e. the recess 5, made in the wall of the channel increases according to R.

Claims (4)

5 68108 A shut-off valve for flue gas ducts or the like, comprising a shut-off member 5 (2) pivotable on the shaft (4), the second wall (1a) of the passage (1) parallel to the shaft (4) having a recess (5) for receiving the shut-off member (2) when the valve is open, characterized in that the shaft (4) of the closing member is hollow, in which a pivot shaft (9) with eccentric members (10) supporting the axis (4) of the closing member 10 mounted on the wall of the channel is arranged inside it. (2) can be pivoted from the open position first along a circular arc to the closed position and then by pivoting the pivot axis 15 with eccentric members in a manner known per se in the longitudinal direction of the channel, and that the channel walls have Shut-off valve according to Claim 1, characterized in that the shaft (4) of the shut-off element is provided with cover flanges (14) sliding along the inner surface of the duct walls and with external seals (15, 16). A shut-off valve according to claim 2. 25 characterized in that the outer seals comprise a cover flange and a sealing ring (15) abutting the edge of the channel wall opening and an annular plate (16) attached to the wall of the channel externally with a conical collar (17) for pressing the sealing ring into place. Shut-off valve according to Claim 1, characterized in that a counterweight (20) is connected to its shaft in order to facilitate the pivoting of the shut-off element.