DE7810824U1 - Hydraulic screw ring clamping device for opening and closing pressure vessels - Google Patents

Description

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M.Schaaf - Hydraulics - Screws .-: Spejnnjtjechnik * "* - *

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Characters: G- 78 1 ο 824.4

description

Hydraulic screw ring clamping device for closing and opening of pressure vessels.

The invention relates to a method known per se screw clamping device in ring design with hydraulic piston retraction (DBP 1425 and German 3-usage sample G- 7o21275) for the simultaneous tightening and loosening of Deekel screws on pressure vessels, especially on inspection openings on steam generators in nuclear power plants.

The opening and closing of the aforementioned openings are advantageously carried out with the aforementioned ¹ - ^ xngspannvorrichtungen Pig.I Eum simultaneous tensioning of the cover screws. Although these known devices allow equal expansions of the cover screws 18 by simultaneous pressurization of the annular piston 2, which via the application pressure ( Manometer) are controllable, but do not offer any final security against the requirements for the highest operational safety, because the required equal tension of all cover screws is generated at the same time, but is held mechanically by re-screwing all adjusting nuts 3 and then releasing the oil pressure less of influence on the remaining tightening forces

7810824 10/12/78

M. Sc.iaaf - Hydraulics - Screws ,, · * - Spaim.teclinik.

Sign: G 78 1o 824.4

Description sheet 2

than the state of the contact surfaces between adjusting nuts 3 and cover flange 5. Small impurities cannot be overcome by the adjustment torque and this can result in differences in the remaining preload forces, the operational uncertainty through leakage or overloading of individual screws.

Unnoticed drop in application pressure cause between piston 2 and cylinder 1, as well as omitting readjustment of the adjusting nut 3 same operational uncertainties and malfunctions as mentioned above. The proposed ring tensioning device According to Fig.I eliminates the aforementioned disadvantages in that in the ring clamping device built-in ileßstangen 6, each with two dial gauges 7 the expansion path of all screws over the entire Record the tensioning process and thus show the decisive remaining elongations of the entire screws.

This measurement method, known per se, enables a tension log to be drawn up especially for the sealing of manhole covers on steam generated in nuclear power plants of is paramount.

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M. Schaaf - Hydraulics - Screws - jSpa & ti'beQhnik] ··)

I sign: G- 78 1o 824.4

Description sheet 3

A further increase of the operational safety of the known Ringspannvor- j directions with hydraulic return 8 of the max.Hubes the \ annular piston 2 vorgeschlagen.Bei reaching 8o% of max.Hubes the annular piston 2 triggers of an automatic prompt bezw.Signalgebung air or Electrically operated limit switches 9 emit an acoustic and optical alarm signal. This prevents the ring pistons 2 from escaping from the ring cylinder 1 and thus preventing oil from escaping into the reactor building. The measuring pin 1o visually indicates the absolute end stroke when the plane is identical with the annular piston retraction plate 11. Another significant improvement in terms of time savings for the tensioning process is the proposed arrangement for storing the support nut 4 on the annular piston retraction plate 11 in the immediate vicinity of the position of use. Any time savings, especially when opening and closing manhole covers on steam generators in nuclear power plants, are great This is important because the operating personnel can only be deployed for a limited period of time.

7810824 10/12/78

M.Schaaf - Hydraulics - Screws, .r · '. Clamps aciinik:

List of reference symbols

1 = ring cylinder

2 = ring baskets

3 = adjusting nut 4- = supporting nut

5 = cover flange

6 = measuring rod

7 = dial indicators

β = Signalgebubg not applicable

9 = limit switch

10 = measuring pin

11 = basket retraction plate

12 = tank flange

13 = two-part clamping ring

14 = spring

15 = not available

16 · - control edge

17 = 11, therefore not applicable

18 = expansion screw

19 = Gev / indestopfen

7810824 1110.78

Claims (3)

M.Schaaf - Hydraulik - Sehrauben / \ - j gffiV characters: & 78 1 ο 824.4 Protection claims 1. Hydraulically "operated ring tensioning device according to. Fig. I in one or multi-stage or two-part design for simultaneous tensioning of several expansion screws, tie rods or the like according to Pig.I characterized in that a two-part clamping ring 13 or fixed support cams on the base flange, the base measuring surfaces for the Keßstangen 6 pictures.. 2. Apparatus according to claim 1, characterized in that axially "movable and measuring rods 6 under spring tension 14, each with two dial gauges 7, provide a unit with the ring cylinder 1 "form. 3. Apparatus according to claim 1 and 2, characterized in that the ring piston return plate 11 is provided with a control edge 16 for actuating the limit switch 9. y 4 · Device according to claims 1-3 ; characterized in that the tCnd- switch 9 is part of the ring cylinder. I "5. Device according to claims 1-4 j characterized in that the \ Piston retraction plate 11 with '■ threaded plug 19 is equipped and external thread of this plug dem ) f Internal thread of the support nut 4 I.
is equivalent to. 7810824 10/12/78