CS265773B1 - Closing flap - Google Patents

Abstract

closing flap for separation flue gas space of the boiler air heater type Ljungstrom with rails embedded outside the abrasive effect effects. Sheets are welded to shafts which are stored in rolling bearings, placed on the outside of the frame. control sheets is a servo drive, lever mechanism. It is possible to use all of them types of boilers where the project is being considered with LjungstrSm air heaters.

Description

The invention relates to a shut-off flap located in the flue gas duct of a steam boiler and to a close closure of the flue gas duct between a second draft of the boiler and an air heater of the Ljungstrom type.

The existing shut-off flap valves installed in the flue gas ducts upstream and downstream of the Ljungstrom air heater do not, by their design, ensure the tightness of the combustion duct. According to their design, the closing blades, the leaf frames and the internal slide bearings are permanently in the flue gas flow. 2 of this reason, after two to three months of operation of the boiler, the inner bearings of the flap valves are sealed and at the same time, the closing leaves and the leaf frames wear strongly, causing permanent damper leakage and immobility. These dampers therefore do not allow boiler operation or reduced output in the event of failure or shutdown of one Ljungstrom air heater, since shutting down the dampers cannot protect the shut-off Ljungstrom air heater from thermal stress and it is not possible to carry out any maintenance work.

The aforementioned drawbacks are overcome by a shut-off flap according to the invention, which consists of a frame in which two parallel shafts are fitted with two arms, both shafts being housed in roller bearings located on the outside of the frame and actuated by a servo-actuated lever. position sealed by means of a gasket mounted on the beam in the clips.

The advantages of the invention are that it allows the operation of boilers with only one Ljungstrom, allows repairs to operational and other failures in the emergency shutdown Ljungstrome, to perform inspection, maintenance, basket washing and intermediate repairs at Ljungstrome during its planned shutdown during boiler operation.

In the accompanying drawings of FIG. 1 is a top view of the Ljungstrom air heater shutter; FIG. 2 shows a detail of the seal of the damper arm at the shaft in the working position, FIG. 3 detail of beam with protector and sealing sheets. In FIG. 4 is a schematic representation of the operation of the shutter flap by a lever mechanism

The shutter flap comprises a flap frame 7 in which the flap arms 2 are welded to the shafts 2, which are mounted in rolling bearings located outside the frame. The actuation of the damper arms is actuated by a lever mechanism thereof. The hermeticity of the flap arms in the closed-working position is solved by means of a seal 2 housed in the clips j>. The retainer 5 with the retainer serves to fasten and protect the sealing elements against abrasion. The tubular perforated ring 4 provides for the displacement of the deaf spaces from possible deposits by means of compressed air.

Claims (1)

Shut-off flap for separating the flue gas space of a steam boiler from a Ljungstrom pre-heater characterized by the fact that it consists of a frame (1) in which two parallel shafts (3) are mounted on two parallel shafts (2). located on the outside of the frame (1) and actuated by the actuator (9) by means of the lever mechanism (8) and the arm (2) are sealed in the closed position by means of a seal (7) mounted on the support (5) in the clips (6).