CS245169B1 - Internal boiler installation equipment for steam boilers - Google Patents

Abstract

The purpose of the proposed device is to replace the functionally unsuitable screw connections of the drum assemblies of steam boilers with another functional principle. This purpose is achieved by the device consisting of a collection chamber connected to the bores of the drum shell by a metal cylindrical sleeve, which is either welded or rolled to both parts. In this way, the steam-water mixture is transferred from the transfer pipes to the collection chamber and to the cyclones without any problems. The device of this design can be used primarily in mechanical engineering.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a device for the internal installation of steam boiler drums.

The installation of high pressure steam boiler drums must ensure perfect separation of salts and non-Hanic impurities from the steam produced so that the steam produced meets the requirement for trouble-free long-term operation of the equipment where the spring is used.

In the case of high-pressure steam boilers, cyclone installations are generally used. The perfect function of separation of moisture and impurities of the steam mixture is ensured in the cyclone itself. The supply of the steam-water mixture from the transfer pipes to the cyclone is controlled by a so-called collecting chamber. The collecting chamber encloses the space between the inner surface of the drum jacket in the region of the bores in the steam supply jacket and the cyclone inlet.

For technological and construction reasons, screw connections have been chosen to connect the collecting chambers to the drum. The flat steel, which forms the transition element between the collecting chamber and the inner surface of the drum, has been bolted to the drum housing at suitable intervals. However, due to the unevenness of the inner surface of the drum sheath, this connection does not ensure tightness. In more recent designs, the flat steel has already been welded to the inner surface of the drum, but the leak problem has been transferred to the next screw connection between this element and the steel surface of the collecting chamber.

Due to leakage, the water fraction from the steam mixture into the steam space of the drum penetrated, salt and impurities from the penetrated water mixture worsened the quality of the saturated steam produced with other subsequent negative consequences, consisting mainly in salt deposition in boiler superheater systems, turbine blades or heat exchangers.

In unsteady operating states of the boiler, especially when starting due to different dilatations of the thick-walled drum and collecting chamber made of thin-walled sheets, the resulting expansion forces cause the bolts to break. As a result of breakage of the screw connection, the above-described phenomenon of water fraction penetrating into saturated springs becomes so large that power plants operate with reduced efficiency and incur significant economic losses for power plant operators due to necessary plant downtime. So far, no way has been found to improve the condition of the drums, in particular.

Disadvantages of the prior art are completely eliminated by the internal installation of the drums of the steam boilers according to the invention which comprises a collecting chamber. SUMMARY OF THE INVENTION The invention is based on the fact that cylindrical metal sleeves are connected to the collecting chamber and are connected on the opposite side by a sealed cylindrical joint. The bore of the drum housing is formed by a welded connection. The collecting chamber may be divided in planes perpendicular to the longitudinal axis of the drum.

The outer diameter of the cylindrical bushing with minimal clearance is aligned with the diameter of the bore in the drum and its length provides optimum conditions for making tight, technologically simple connections with the inner surface of the drum on one side and the collecting chamber on the opposite side. This solution completely eliminates leakages and thus negative effects of impurities penetration into the produced saturated steam, which resulted in breakdowns and considerable economic losses at the operators of power plants.

In addition, this design allows the structural chamber to be easily divided into several sections along the length of the drum. The advantage of the separated collecting chamber is that the difference between the dilatation of the drum itself and the collecting chamber is reduced to a constructionally permissible value, thus avoiding disturbances which could be caused by rapid changes in the operating conditions of the steam boiler drum.

An exemplary embodiment of the device according to the invention is shown schematically in the accompanying drawings, in which Fig. 1 is a part of the internal installation of the steam boiler drums;

In the embodiment of FIG. 1, the collecting chamber 2 is closely connected to the inner shell of the drum 2. The steam mixture is transferred to the chamber 2 by bushings 1. The bushing 1 is a smooth cylindrical body made of metal, malleable and weldable material. The design of the casing 2 and the design of the collecting chamber 2 allow a tight connection of these parts to the inner bore of the drum 2. It is possible to make a weld joint between the casing 1 and the collecting chamber 2 without technological difficulties.

FIG. 2 shows an embodiment of the collecting chamber 2 divided in planes perpendicular to the longitudinal axis of the drum 2.

Claims (2)

An internal installation of drums of steam boilers comprising a collecting chamber, characterized in that cylindrical metal sleeves (1) are connected to the collecting chamber (3), connected on the opposite side by a tight cylindrical joint (5) with boreholes of the drum (2). wherein the connection of the sleeves (1) to the collecting chamber (3) is made by a weld joint (4). 2. Internal boiler drum installation, characterized in that the collecting chamber (3) is divided in planes perpendicular to the axis of the drum (2).