RU2131386C1 - Method of sealing-up defects in envelopes of objects and device for realization of this method (versions) - Google Patents

Abstract

FIELD: mechanical engineering; repair of defects in articles revealed visually or during testing them for tightness under internal pressure, for example, parts of pneumatic equipment mounted on space object. SUBSTANCE: method includes forming rigging in area of defect, filling this area with sealant through filler hole in rigging; inner surface of rigging is made closed and is coated with nonwettable composition; sealant is subjected to degassing before using it. Device used for realization of this method has cover with seal, hold-down made in form of beam with central adjusting screw; cover is provided with handle and longitudinal slot; beam has longitudinal slot perpendicular to slot of cover; adjusting screw is passed through floating nut mounted in slot of beam; ends of beam are passed through two uprights equipped with collets which are secured on projecting structural members of space object and are tightened-up by means of nuts; cover has hole for pouring the sealant. Device is also provided with spring-loaded hold-down having central hole and handle with hole for pouring the sealant; axis of this hole coincides with axis of hole in hold-down. The invention ensure sealing-up of defects (extended defects inclusive) in space object envelopes during flight, i.e. in case of weightlessness and pressure differential from 5 to 20 mm Hg inside object to space vacuum of 10^-5 mm Hg. Repair may be performed on side of lower pressure and in vacuum; after repair, space object envelope shall withstand pressurization to normal pressure and hold this pressure within required period of time. EFFECT: enhanced efficiency and reliability. 4 cl, 3 dwg

Description

 The invention relates to the field of mechanical engineering, namely the repair of defects on products detected visually or when testing them with internal pressure for leaks, for example, parts of pneumatic fittings mounted on KO.

 It is generally accepted that sealing can be superficial and intra-sutural. During surface sealing, the sealant is applied in the defect zone, while the sealant contacts on one side the surface being cleaned, and on the other, with the medium.

 With intra-seam sealing, contact surfaces to be joined are joined (for example, flanged joints).

 Known methods for repairing worn surfaces by pouring with polymer (for example, and.with. N 193849, B 23 P 6/00).

 There are also known methods of restoring machine parts by washing the repaired surface with acetone followed by applying a putty based on epoxy resin and iron powder (Molodykh N.V., Zenkin A.S. Restoration of machine parts. M .: Mashinostroenie, 1989, p. 217).

 A known method of sealing a defect in an article, comprising filling a defect with a sealing composition in the form of an epoxy resin and an iron-containing powder, followed by curing, wherein after filling the defect with a sealing composition and curing, the outer surface is cleaned until a metallic luster appears, and then the sealant is applied again (Patent No. 2084323, B 23 P 6/00. RF).

 The disadvantage of analogues is the impossibility of using them to repair extended structural defects in zero gravity and vacuum conditions, since under zero gravity the sealing composition tries to occupy the minimum volume due to the surface tension force, and guaranteed filling of the extended defect with the sealing composition becomes practically impossible. Gases released from the composition in a vacuum also impede the guaranteed filling of the defect with the composition.

 An analogue of the proposed method is a groove sealing method, in which a closed volume is created above the defect zone using special equipment, then a hardening sealant is poured into it (Adhesives and sealants. Edited by D. A. Kardoshov. M .: Chemistry, p. 170) .

 The disadvantage of this analogue is the impossibility of reliable filling of the formed closed volume in zero gravity conditions without special processing of equipment and preliminary degassing of the sealant.

 An analogue of the device for sealing defects in the shells of space objects is a technical solution for AS N 1712118, B 23 P 6/00, in which the device is made in the form of a pressure plate with technological bolts, which is mounted in the zone of the defect and presses the sealant applied to the defect, after curing, the plate is removed.

 The disadvantage of the analogue is the impossibility of using such a device, since the installation of technological and subsequently removed bolts is unacceptable on an extended, leak-tight casing.

 An analogue of a sealing device is a device for a.s. N 1636167, B 23 P 6/00, made in the form of a bracket with curved legs, at the ends of which spikes are made, and the middle part of the bracket is curved for better tightening and clamping.

 The disadvantage of the analogue is the impossibility of its use in space conditions, since in this solution the sealant layer must be applied before the clamp is installed, which is impossible in zero gravity due to the sealant taking the shape of a ball, and, as a result, is unacceptable for repairing extended defects.

The objective of the invention is the provision of sealing defects (mainly extended) shells of space objects in space flight, i.e. weightlessness and pressure drop from 5 - 20 mm Hg inside the facility to a vacuum overboard 10 ^-5 mm Hg

 At the same time, repairs can be carried out only from the side of lower pressure and in a vacuum, and after repair of the object, the KO shell must withstand pressurization to normal pressure and hold it for the required time.

 This problem is achieved by the fact that in the method of sealing defects in the shells of space objects (KO), including the formation of snap in the defect zone, filling this zone with sealant through the filling hole in the snap, the inner surface of the snap is closed, cover it with a non-wettable composition, and the sealant is degassed before filling .

 The proposed method for sealing defects in shells of space objects (KO) is implemented as follows: the surface along the defect is thoroughly cleaned with a metal brush, dust is removed from the sealing zone with a hair brush. A snap is installed above the sealing zone, while creating a closed volume. Preliminarily, a composition is applied to the tooling from the inside, preventing the wetting of the tooling surface with a sealant. After the snap-in is installed, the sealant is introduced into the formed volume, the adsorbed air is previously removed from the components by vacuuming the sealant components in a vacuum chamber, for example, for 3 hours.

Before evacuation, the sealant is placed in a syringe, which is then evacuated together with the syringes. In this case, the pressure in the vacuum chamber is gradually reduced to prevent the displacement of the sealant from the syringe. For example, the following degassing mode is selected as a cryosilic sealant: the first 30 minutes, degassing is carried out at 20 mm Hg; then the pressure was lowered to 10 ^-1 atm. and withstand sealant for 1.5 hours; after that, continuous pumping of the sealant is carried out with a foreline pump for 2 hours.

 Further, the sealant can be injected into the equipment by filling with a syringe.

 This problem is also achieved by the fact that in the device for sealing defects in the shells of space objects (KO) (option 1), containing a cover with a seal, a clamp in the form of a beam with a central adjusting screw, the cover is equipped with a handle and has a longitudinal groove, and in the beam a longitudinal a groove perpendicular to the groove of the lid, while the adjustment screw is passed through a floating nut installed in the groove of the beam, while the ends of the beam are passed through two racks with collets mounted on the protruding structural elements of KO and tightened holes, and in the lid there are made filling holes for the sealant, and the inner surface of the lid is covered with a non-wettable sealant composition.

 The task is also achieved by the fact that in the device for sealing defects in the shells of space objects (KO) (option 2) containing a spring clip, the clip has a central hole and it is equipped with a handle with a filling hole, the axis of which coincides with the axis of the clip hole, and the inner the surface of which is coated with a non-wettable sealant.

 In FIG. 1 shows a device for sealing defects in shells of space objects (KO) (option 1); in FIG. 2 shows the aforementioned device from above; in FIG. 3 shows a device for sealing defects in the shells of space objects (KO) (option 2).

 The proposed device for sealing defects of the shells of space objects (KO) (option 1) consists of racks with collets (1), mounted on the protruding structural elements of the KO using nuts (3); a beam (clamp) (4) is passed through the racks with collets, the ends of which are fastened with nuts (2) with the help of studs (11) passing through the washers (5). The device includes a cover with a handle (6) with a seal (8). The beam (4) has a central adjusting screw (7), which is passed through the floating nut (10) installed in the groove of the beam. The cover (6) is pressed by the screw (7) until the seal (8) touches the KO casing. The inner surface of the lid (6) is covered with a non-wettable sealant composition (12). As a seal, for example, foam rubber can be used.

 The device for sealing defects in shells of space objects (KOs) (option 1) operates as follows: install racks with collets (1), putting on the collets tightly on the ribs or other protruding structural elements of the KO and turn the collet nuts (3) fully clockwise. On the studs (11) put on the beam (4), threading the studs (11) through the washers (5), fix the beam on the studs (11) with nuts (2), orient the cover with the handle (6) relative to the damaged area, press the cover with the handle ( 6) using the screw (7) until the seal (8) touches the CO skin, then give two more turns with the screw (7) clockwise. Then through the filling holes (9) pump the sealant.

 The sealing device for defects in the shells of space objects (KO) (option 2) consists of a spring clip (2), in which a central hole (3) is made. The clamp (2) is equipped with a handle (1) with a hole for filling (4). The inner surface of the spring clip (2) is coated with a non-wettable sealant composition (5). The axis of the fill hole (4) coincides with the axis of the clip hole (3).

 The device for sealing defects in the shells of space objects (KO) (option 2) operates as follows: by pressing on the handle (1) a spring clip (2) is put on the edges of the KO shell or its other protruding structures. From the clamps you can make any mosaic by installing them one next to the other, covering the area to be repaired.

The implementation of the inner surface of the snap-in installed in the area of the defect of KO, coating its inner surface with a non-wettable composition, and degassing of the sealant before filling in combination with the distinctive design features of the devices for implementing this method (option 1 and option 2) allow achieving the goal - sealing defects (mainly, extended) shells of space objects in space flight conditions: weightlessness and pressure drop from 5 - 20 mm Hg inside the facility to a vacuum overboard 10 ^-5 mm Hg

 In this case, repairs can be carried out from the side of lower pressure and in vacuum conditions, and after repair of the object, the KO shell must withstand pressurization to normal pressure and keep it for the required time. It is possible to use the device from the inside of the TO.

 The manufacture of devices for sealing defects in shells of space objects (KO) does not require special technology and equipment. Component devices according to option 1 can be made by turning and milling method. The device according to option 2 can be manufactured by sheet metal stamping with a bore of the filling hole.

Claims (3)

 1. A method of sealing defects in the shells of space objects, characterized in that they form a closed volume above the defect zone with the help of a tool, apply an unm wettable composition to the internal surface of the tool, and fill the closed volume with a previously degassed sealant.  2. A device for sealing defects in shells of space objects, characterized in that it comprises a cover with a seal, a handle and a longitudinal groove, as well as filling holes for the sealant, a clamp made in the form of a beam with a longitudinal groove oriented perpendicular to the groove of the lid installed in the aforementioned a groove, a floating nut, a central adjusting screw passed through it, two racks with collets, mounted on the protruding structural elements of the space shells and tightened nuts, in which enes end of said beam.  3. A device for sealing defects in shells of space objects, characterized in that it comprises a spring clip with a central hole and a handle with a filling hole for the sealant, coaxial with the clip hole.

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