DE1051355B - Expansion vessel for electrical systems, especially for cable systems - Google Patents

Description

The invention relates to the formation of pressure equalizing devices on cable systems whose ^1, the variations in volume caused by the different loading of the cable are both oil-filled cables with normal as well as a higher oil pressure, so-called oil pressure cable, collected by.

The known balancing devices arranged outside the cable at some distance from it have the task of dealing with fluctuations in the volume of the oil in the cable caused by the various electrical cable load is created by a more or less resilient organ, a counter pressure to generate the cable oil. In the known devices, this organ preferably consists of metallic bodies, so-called cells, whose volume is increased by squeezing these bodies can be changed. They have essentially become known as round, simple or circular grooved membranes.

Such flexible cells are installed in the known arrangements in housings, so that, for. B. the space surrounding the cell is connected to the oil cable by pipelines, while the space inside the cell is filled by an agent, with the help of which it enters the flexible cell wall appropriate counter pressure can be exerted. As a means of pressure, also as an external means of pressure called, oil and gas are known.

The cells with grooved or not grooved circular membranes advantageously have only one very low dead volume, as they are able to move through their stroke due to their special construction to traverse almost the entire volume of the housing in which they are installed. The good use the volume of the housing through the cell stroke is in itself in the interest of a small amount of expenditure for the external pressure medium, i.e. primarily oil, in particular also very desirable when using several cells. This is especially important when the Cable oil counterpressure acting over the cells is generated by +0 the cushioning effect in the housing. In this is the case when the pressure in the cable oil rises and the volume increases accordingly The corresponding counterpressure in the cell on the other side of the cell wall is all the steeper +5 lying housing volume take place, the smaller this volume is.

There are now expansion vessels with metal bellows with a grooved, flexible jacket as Compensating cells have become known, but they have the major disadvantage that they always work with a very large dead volume, which has the already mentioned disadvantage of the function in terms of function brings flat pressure rise with it. So have from dammmgs äß

for electrical systems,

especially for cable systems

Applicant:
Kabelwerk Rheydt AG, Rheydt (RhId.)

Dr. rer. nat. Heinz Heumann, Wickrath / Niers,
has been named as the inventor

Such metal bellows or corrugated hoses only have a longitudinal stroke of about 15 to 20%>, so that the The volume that is closed off by such a corrugated tube can only change by 15 to 20% can, while the remaining space in the corrugated tube is 80 to 85% dead volume with the mentioned Disadvantages.

The invention is therefore based on the object of using such commercially available corrugated tubes, however, to avoid the disadvantage of the large dead volume. The invention solves this problem by that the dead space of the corrugated tube up to the functionally required volume by arranging fixed components and / or further folded tubes arranged one inside the other is reduced in size.

In the drawing, which shows an example of an expansion tank according to the invention, the corrugated hose F is in a housing G. On one side, the corrugated hose is open and sealingly connected to the housing at D , while the corrugated hose on the other side through the Floor B is complete. A cylindrical closed hollow body is inserted into the corrugated tube, the size of which is determined by the fact that the corrugated tube does not touch the cylindrical cavity in the state of greatest contraction or that only a very small distance remains between the two. This cylindrical cavity can of course be kept open on the opposite side which closes the bellows, so that the cylindrical space turns into the corrugated tube in an approximately pot-like manner. The corrugated tube can be moved arbitrarily between the inner vessel bottom α and the outer vessel bottom b without a significant dead volume remaining in the space enclosed by the corrugated tube when the contraction is greatest. The volume between the folds

809 767/388

Claims (4)

hose and the inner vessel walls α and c can therefore, due to its small size, when the cable oil pressure increases, generate a counterpressure in a much steeper manner than was possible with the previously known devices. According to a further embodiment of the invention, one or more further bellows can be arranged in the pot-like cavity instead of fixed components or in addition to them. In this way, too, the dead space can also be reduced to the desired extent. The corrugated tubes of the expansion tank can be made of metal, such as. B. brass, as well as made of steel. However, they can also be formed from non-metallic material, advantageously from the swelling movements only with a relatively significantly lower mechanical resistance and plastic that is inert and impermeable to the adjacent liquids or gases. It is particularly advantageous that the corrugated tubes are vertical in the expansion vessels. The arrangement shown in the drawing can also be installed in a spatially reduced form in the pot formed by the vessel walls and c. This may be necessary for reasons of economic production or in the case of limited space. This arrangement proves to be particularly favorable when the expansion vessel according to the invention is to be installed in the transport drum of an oil cable in a space-saving manner. Patent claims: 1. Expansion vessel for electrical systems, especially cable systems, from the electrical Part of the system, such as B. the oil cable, is spaced apart and made of pressure-equalizing, z. B. by means of gas filling against the cable oil pressing metallic cavernous bodies, in particular Bellows or corrugated tubes, characterized in that their lifting dead Space except for the functionally required volume by arranging fixed components and / or one inside the other arranged further folds is reduced. 2. Expansion vessel according to claim 1, characterized in that the one or more metallic Cavernous bodies, such as in particular bellows or corrugated tubes, made of non-metallic material, advantageously made of plastic. 3. Expansion vessel according to claim 1, characterized in that the creases against each other or against the vessel walls on the gas and / or oil side through against the filling Medium inert, consisting of organic or inorganic, preferably elastic material Protective padding are supported. 4. Expansion vessel according to claim 1 or 2, characterized in that the corrugated tubes stand vertically in the expansion vessels. Considered publications:
German patent specifications No. 886 610, 936 224. 1 sheet of drawings ® 809 767/388 2.59