DE1074340B - Lid lock for high pressure container - Google Patents

Description

GERMAN

The invention relates to a lid closure for high pressure containers. The invention is particular applicable to valve chambers as used in steam turbine systems.

For fastening lids of high pressure vessels subject to extreme temperature and pressure conditions, ζ. B. valve chambers, so far mostly screw bolts have been used. With the present z. B. in steam turbines and related systems occurring high pressures and temperatures as well as in With regard to the likelihood of further increases in these pressures and temperatures in the future The difficult problem arises of preventing such closure caps from becoming sealed without being used to fasten excessively strong and heavier screw bolts, especially at temperatures such as at which creep phenomena occur in the material of the screws.

The invention aims to design such a closure that connections with screw bolts of relatively small dimensions even in the presence of extreme pressures and temperatures suffice.

The invention relates to a container closure of known type with a hanging lid trained, inserted into the container opening closure lid, which is divided into segments by a and supported in an annular groove of the container wall engaging support ring against axial displacement is. The invention is characterized by an additional outer lid that covers the edge of the container opening sealingly covered and z. B. is fastened with bolts on the container, with the between the inner cover and the outer cover resulting intermediate chamber connected to a pressure medium source whose pressure is lower than the pressure inside the container, but higher than that Ambient pressure. In the case of valve chambers for high-pressure steam turbines, this pressure medium source can be the outlet of the turbine.

In the arrangement corresponding to the invention, the support ring is only subjected to shear forces, which by the pressure difference acting on the inner lid between the interior of the The vessel and the intermediate chamber. Only the opposite acts on the outer cover the internal pressure lower pressure in the intermediate chamber. The pressure in this chamber is set so that that the stresses expediently on the support ring of the inner cover and the screw bolts of the outer cover are distributed.

The invention will be explained with reference to the drawing, for example. It shows

Fig. 1 is a longitudinal section through the opening of a

Applicant:

Metropolitan-Vickers Electrical Company Limited,
London

Representative: Dr. M. Herzfeld, patent attorney,
Düsseldorf, Kreuzstr. 32

Claimed priority:
Great Britain 3 February 1956

Joseph Clare London,

Sharks Barns, Altringham, Cheshire,

and John Garland, Chadderton, Lancashire

(Great Britain),
have been named as inventors

Valve box of a high-pressure steam turbine with a cover closure designed according to the invention,

FIG. 2 shows a section in the direction of the arrows along line XX in FIG. 1.

In the drawing, A is a part of the container wall that surrounds the opening to be closed. The opening can have a circular or rectangular cross-section, depending on the particular construction of the container.

The entire closure consists of an inner lid 3 and an outer lid 3 a, which are attached to the container and enclose an intermediate chamber 2 between them. The interior of the container is provided with the reference number 1. The cover 3 is held in the container opening by a Stützring4 while the lid 3, for example, by a number of bolts is fastened in a conventional manner 10th

A through opening (not shown in the drawing) is provided in the cover 3 α in order to enable the intermediate chamber 2 to be connected to a pressure medium source.

During operation, the interior 1 is under full live steam pressure at the corresponding temperature, while the intermediate chamber 2 is connected to a part of the turbine system in which a low

909727 / 27Ϊ

There is more pressure, like ζ. B. with the outlet end of a high pressure turbine. The inner lid 3, which is slidable Is fitted into the container opening, can be inserted into the support ring 4 by means of a Flange ring 5 and studs 9 are tightened sealingly in a manner known per se. This is however not essential, since the internal pressure in the container ensures that the inner lid 3 against the support ring 4 is pressed. For assembly reasons it is necessary to divide the support ring into three or more segments to share. The retaining ring advantageously consists of three segments, two of which are of equal length, while the third is shorter and about a quarter of the circumference the container opening includes. The parting lines 6 between these segments are, as per se as well known, in parallel planes, the parting line between the abutting ends of the two longer segments runs radially to the container opening.

These joints together with the joints 7 and 8 on the contact surfaces of the support ring are the only leakage paths between the interior 1 and the intermediate chamber 2. The outer cover 3 α and its screw bolts 10 only need to be dimensioned so strong that they can withstand the stresses caused by the pressure in the intermediate chamber 2. This avoids constant monitoring and tightening of the cover screws, which is necessary in the case of container closures whose screw-fastened cover is directly exposed to the internal pressure and the high temperature of the live steam because of the creep phenomena that occur.

In the case of valve bodies with multiple openings that are adjacent to each other, each opening can have a Inner cover 3 be closed, while only a common outer cover is provided, which all Covered openings to form a common intermediate chamber.

Claims (3)

PATENT CLAIMS: 1. Lid closure for high pressure containers, in particular for valve chambers of high-pressure steam turbine systems, with a hanging cover that is inserted into the container opening Inner lid, which is divided into segments and engages in an annular groove in the container wall Support ring is supported against axial displacement, characterized in that in addition to the Inner lid (3) also covers the edge of the container opening in a sealing manner and on the container z. B. by screw bolts (10) attached outer cover (3 a) is provided and an intermediate chamber (2) between the inner cover (3) and the outer cover (3 a) with a pressure medium source is connected, wherein in the intermediate chamber (2) a pressure is maintained that is lower than the internal pressure in the container (1) but higher than the ambient pressure. 2. Lid closure according to claim 1 for valve chambers of high pressure steam turbines, characterized in that the intermediate chamber (2) is connected to the outlet of the high pressure steam turbine and the interior (1) of the valve chamber (A) is connected to the inlet of the turbine. 3. Lid closure according to claim 2, characterized in that in the case of valve housings with several adjacent openings each opening has an inner lid, while all Openings from a common outer cover to form a common intermediate chamber are covered. Considered publications:
German Patent No. 223 816;
British Patent No. 362,724;
U.S. Patent Nos. 2,278,882, 2,690,275. 1 sheet of drawings © 909 727/279 1.60