EP0935117B1 - Method for force fitting a tubular liner in the outer tubular case of a gun barrel - Google Patents

Description

The invention relates to a method for producing a non-positive connection of a casing with the Jacket tube of a barrel weapon by shrinking. Such a method is known from US Pat. No. 2,915,946 A, the casing pipe being cooled to a temperature below -50 ° C., the casing pipe being heated to a temperature in the partial region in which it is to be connected to the casing pipe, which is chosen in this way is known that its inner diameter is larger than the outer diameter of the casing and the casing is then inserted into the casing.

To reuse the fired gun barrel as intended to be able to drill the pipes has long been known and then with a thin, not self-supporting To feed the pipe (see e.g. Rheinmetall "Weapons Paperback "7th unchanged edition 1985, Düsseldorf 1980). The casing pipes are with the casing pipe, e.g. by shrinking, usually the Jacket tube heated and the casing tube cooled by water becomes.

Especially when using casing pipes with a large one L / d ratio has proven disadvantageous in that Application of this known joining process the joining game between the casing and the casing pipe is very small, because at Heat shrink a maximum upper temperature of the casing tube must not be exceeded. Otherwise there is a risk that the residual stress state of the corresponding gun barrel are destroyed would.

The present invention is based on the object relatively long and thin-walled casing pipes on simple Wise and very accurate with the jacket pipes accordingly Connect barrel weapons.

This object is solved by the features of claim 1. Disclose further advantageous refinements of the invention the subclaims.

Essentially, the invention is based on the idea that To increase the joint play between the casing and casing pipe, that in addition to the heating of the casing tube Cooling of the casing below a value of -50 ° C, preferably to -70 ° C.

If the casing is inserted into the casing pipe first cooled even further, the shrinking process proceeds advantageously slowly at first, because that heated (shrinking) casing pipe to no immediate leads to substantial heating of the casing and thus also no major increase in diameter of the casing causes.

To cool the casing, this is preferably done with Dry ice filled. If the cooling is not in the Vacuum or in a room filled with protective gas, due to the humidity in the area outside of the casing during the cooling process be protected by an insulating layer.

The heating and cooling of the jacket tube should be in some areas be controllable in such a way that the jacket tube first the middle area of the casing and only after one given time also on the remaining side areas the casing is shrink-fit.

Fig.1

den Längsschnitt durch ein Waffenrohr, bei dem das Futterrohr nach dem erfindungsgemäßen Verfahren in das Mantelrohr eingeschrumpft wurde;

Fig.2

einen verkleinerten Längsschnitt auf einem Fixierdorn angeordneten Futterrohr bei dem Abkühlvorgang und

Fig.3

den Längsschnitt durch ein auf das Futterrohr aufgesetztes Mantelrohr bei dem Schrumpfungsvorgang.

Further details and advantages of the invention result from the following exemplary embodiment explained with reference to figures. Show it:

Fig.1

the longitudinal section through a weapon barrel, in which the casing was shrunk into the jacket tube according to the inventive method;

Fig.2

a reduced longitudinal section on a mandrel arranged casing during the cooling process and

Figure 3

the longitudinal section through a casing pipe placed on the casing tube during the shrinking process.

1, a weapon barrel of a tank cannon is designated by 1, which consists of a casing tube 2 and a thin-walled Casing tube 3 exists, which is highly loaded on the inside Subarea 4 (in the following also as a joining area designated) of the casing tube 2 and arranged with this is connected by shrinking.

To the casing tube 3 with the casing tube 2 according to the invention connect, the casing 3 is first perpendicular to one Fixing mandrel 5 of a standing device 6 with base plate 7 placed on it and aligned (Fig.2). Around the casing 3 To protect icing when cooling, it is made with polystyrene blocks 8 surrounded and on the top with a polystyrene hood 9 Mistake.

Then the casing 3 is filled with Dry ice 10 via an attachment tube 11. The fixing mandrel 5, the also contains a through hole 12 is also filled with dry ice 10 and cooled. This will uniform cooling over the entire length of the casing 3 reached (depending on the wall thickness and material of the The casing is used for a good cooling of the casing up to 3 hours at approx. -70 ° C).

Parallel to the cooling of the casing 3, heating can take place jacket tube 2 to approx. 335 ° C (+/- 5 ° C). This ensures sufficient heating of the entire joint area 4 is assured, the actual Heating area joining area 4 on both sides by approx. 0.5 m exceed. The heating rate should be between 20 and 30 ° C to ensure sufficient heating of the jacket tube 2 to enable, whereby inductive heating by means of a corresponding heater 13 (Fig.3) in practice as has proven advantageous.

If the casing pipe 2 and casing pipe 3 are in the desired condition, the further heated jacket tube 2 with a lifting device 14 raised at its mouth 15 and over that yet with attachment tube 11 and casing tube 3 surrounded by polystyrene block 8 positioned. This can help simplify positioning at the cargo space end 16 of the casing tube 2 special funnel 17 can be arranged (Fig.3).

The polystyrene block 8 and the attachment tube 11 are then removed, the casing tube 3 is cleaned dry and lightly wetted with a solid lubricant, preferably molybdenum disulfide (MoS ₂ ).

Subsequently, the casing tube 2 is up to the other end 18 of the casing 3 for checking and possibly correcting the positioning lowered. Is the positioning correct, the jacket tube 2 is lowered until that upper end 18 of the casing 3 after passing through Cargo space 19 against the front of the casing delimiting Projection 20 (Fig.1) of the tubular casing 2 abuts.

Then the for the heating of the middle section 21 of the joining area 4 responsible heating part switched off and removed and this part area with air cooled. At the same time, a plug 22 at the bottom End 23 of the stand device 6 are removed so that still existing dry ice 10 can be eliminated and the Casing pipe now faster to the temperature of the casing pipe can heat.

Has the casing tube 2 in the middle section 21 around cooled about 100 ° C, the heating is switched off and that entire jacket tube cooled with air. This gradually Cooling has the effect that the casing tube 2 and the casing tube 3 come first holds in its central portion 21 and then from both sides shrinks over the casing 3. This will avoided that by a longitudinal contraction of the casing tube 2nd a gap formation at the transition between the casing 3 and the front caliber part of the casing tube 2 occurs.

If the temperature of the casing tube 2 has dropped to approx. 50 ° C, can the weapon barrel 1 by means of the lifting device 14 of the Stand device 6 raised and in the appropriate weapon to be built in.

LIST OF REFERENCE NUMBERS

1

barrel

2

casing pipe

3

casing

4

Partial area (casing pipe), joining area

5

locking pin

6

A fixture

7

baseplate

8th

Styrofoam block, insulating body

9

Polystyrene hood, polystyrene block, insulator

10

dry ice

11

joining pipe

12

Bore (fixing mandrel)

13

heater

14

lifting device

15

muzzle

16

End (casing tube)

17

Anführtrichter

18

upper end (casing)

19

cargo space

20

head Start

21

middle range

22

plugs

23

lower end (standing device)

Claims (10)

1. Method of producing a non-positive connection of a liner (3) to the jacketed barrel (2) of a gun by means of shrinking comprising the features:

   a) the liner (3) is cooled down to a temperature below -50°C;

   b) the jacketed barrel (2), in the subregion (4) where it is to be connected to the liner (3), is heated up to a temperature selected in such a way that its inside diameter is greater than the outside diameter of the liner (3);

   c) the liner (3) is then introduced into the jacketed barrel (2), wherein the temperature of the jacketed barrel (2) is held constant;

   d) heating of the jacketed barrel (2) is then terminated and cooling of the jacketed barrel (2) is effected in such a way that the jacketed barrel uniformly shrinks initially onto the middle subregion of the liner (3) and only after a predetermined time also onto the remaining end regions of the liner.
2. Method according to claim 1, characterized in that the liner (3) is disposed vertically on a stand apparatus (6) provided with a fixing mandrel (5), and that for the connection of liner and jacketed barrel (3, 2) the jacketed barrel (2) is disposed above the liner (3) and then slid from above over the liner (3).
3. Method according to claim 1 or 2, characterized in that the liner (3) is cooled by means of dry ice (10) introduced into the liner.
4. Method according to one of claims 1 to 3, characterized in that the liner (3) is cooled down to a temperature of -70°C.
5. Method according to one of claims 1 to 4, characterized in that during the cooling operation the liner (3) is protected at the outside by means of insulating bodies (8, 9) against condensation as a result of air humidity.
6. Method according to one of claims 1 to 5, characterized in that the jacketed barrel (2) is heated inductively.
7. Method according to one of claims 1 to 6, characterized in that the jacketed barrel (2), in the region of the liner (3) that is to be fastened, is heated up to a temperature of between 330 and 340°C.
8. Method according to one of claims 1 to 5, characterized in that for the rate of temperature rise of the jacketed barrel (2) values of between 20 and 30°C/h are selected.
9. Method according to one of claims 1 to 8, characterized in that during the shrinking operation the jacketed barrel (2) is cooled by air.
10. Method according to one of claims 1 to 9, characterized in that immediately before slipping the jacketed barrel (2) onto the liner (3) the latter is provided at the outside with a coating of molybdenum disulphide (MoS₂).

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