DE4003756C1 - Prodn. of polymer shrinkable sleeve - by extruding base member then wetting, stretching and cooling, and forming wall protrusions - Google Patents

Abstract

Prodn. of a shrinkable sleeve made of polymer material, includes extruding a base member, wetting, stretching and cooling. Wall protrusions are formed by the partial bringing together of longitudinal wall sections. The protrusions are shrunk by heat treatment. The base member is pref. coated with adhesive on the inside, and the adhesive is activated by heat treatment. ADVANTAGE - The sleeves can be formed with thick edges, and using a process with reduced tooling and prodn. costs.

Description

The invention relates to a method for producing a with a longitudinal fastener on the ver Thick edges closable shrink sleeve made of poly material, in which a basic body extrudes, cross-links, stretched in a networked state and freezing the Stretching tension is cooled.

From DE-OS 35 11 371 is a method for manufacturing a shrink tube known, initially a Tube of polymeric material extruded and immediately is then fed to a network path. To The hose comes in through the crosslinking section an expansion zone. The tube is in this expansion zone expanded and then in this expanded Zu stood cool.

If such a hose is exposed to heat, the frozen stretching tensions recede and the For example, hose attaches to the under tension Surface of a previously inserted substrate.

DE-OS 37 02 081 describes a process for the production a band-shaped shrink sleeve known in which a Tape with longitudinally formed locking ribs is extruded. After extrusion and cross-linking of the Material transverse to the direction of extrusion for the purpose of Shrinkback stretched and the stretching stresses are switched on froze. The stretched tape is then around the one to be protected Item laid around and over the molded closure ribs closed. After that, by applying heat the cuff produced in this way on the Ge to be protected item shrunk down.  

In the manufacture of such a shrink sleeve the basic profile of the initial value to be generated from it shrinkable cuff. Through the basic profile itself and its dimensions is the shrinkback diameter fixed. The stretching or expanding ratio of a sol Chen band is like expanding a shrink hose depending on the raw material used. Practice Such shrinkage articles are in a ratio of 4: 1 expanded to the original form. From this dependence he is that in the manufacture of shrink sleeves the known type, different tape sizes are extruded must who adapted to the substrates to be spanned the. This requires a high number of tools and production wall.

The object of the invention is a method of ge to create named type in which shrink sleeves but with circumferential expansion with thickened edges a greatly reduced tool and manufacturing effort can be generated. According to the invention is provided hit that on the body by partial, lengthways continuous merging of wall areas term wall protrusions are generated, which under Iso the remaining wall by heat application shrinking outward-pointing circumferential thickenings will.

The method according to the invention is based on the known Her alternatively for shrink sleeves or shrink sleeves on. It can be a production in which the upper already facing the later substrate surface of the base body is coated with an adhesive.  

If a hose is used according to the invention as the base body, such a tube is cut into fixed lengths and clamped in a forming device such that wall areas of the hose loop-like wall protrusions form. These wall protrusions are targeted by Er heat shrinked and can shrink during passage through appropriate molding devices Get profiling. After completion of the partial return shrinking process of the loop-like wall protrusions the hose between the wall protrusions in Split longitudinally and if necessary into the desired length ready-made. The advantage of such a manufacturing it is wise to see that with a single origin tubing of different widths made of shrink sleeves can be. The partial shrinkage of the schleifenar wall protrusions and the additional possibility the further deformation by mold jaws leave the use of a single hose cross-section for production the wider shrink sleeves.

On the other hand, the basic body is a flat, bandför element, the loop-like elements are used Wall protrusions formed from the areas of the tape which after the partial shrinkback the desired size should form thickenings. The procedure is then the same as above to a tubular body per described.

It has proven to be advantageous that the loop fen-like wall protrusions in front of the partial Shrinkback have a continuous cavity. In this continuous cavity can before the partial Shrinkback, for example, longitudinal reinforcement elements are used.  

Such reinforcing elements are useful when closing the shrink sleeve over the circumferential thickening.

It is also advantageous that with the inner circumference adhesive-coated basic bodies of the adhesive through the ge targeted heat application in the area of the wall protrusions activated and when the wall protrusions shrink back for permanent fixing of opposite wall areas the circumferential thickening serves.

It is also appropriate that the peripheral thickening through external shaping forces until the end of the Shrinking process can be brought into shape. The tubular body finally becomes after completion of the partial shrinkage process between the circumferential thickenings separated.

The loop-like wall protrusions and those from them manufactured circumferential connections can according to the invention straight along the surface of the base body be molded. Shrink sleeves produced in this way are used to coat linearly stretched substrates such as pipes, cables and the like. Should mind Diameter differences in the substrate to be covered via be bridged, such as between a cable protection tube and one out of the lumen of this tube led cables exist, so the peripheral thickening also angular on the surface of the shrink sleeve are generated, the angular position between the order catch thickening is freely selectable. That way a shrink sleeve can be created in a single gene shrinking process both the end of a cable protection tube as well as sealing the emerging cable.  

Such shrink sleeves can also be compared apply their problem cases.

In the drawing are schematic diagrams of the manufacturing process driving, based on a tubular body, reproduced; show it:

Fig. 1, the shrink hose clamped in the device with loop-like wall protrusions.

Fig. 2 in the region of the wall protrusions partially shrunk back shrink tubing with additional Verfor processing devices.

Fig. 3 shows the final profile generated after the separation between the thickenings.

Fig. 1 shows the shrinkable tube in the lumen 3 disposed guide tube 1. The guide tube 1 has an axially running recess 11 for receiving coolant. The clamping jaws 2 are raised in the region of the guide tube 1 of the type on the shrink tube 3 that the loop-like wall projections 31 , 32 result between the clamping jaws 2 . The loop-like wall projections 31 , 32 are shown in a form in which there is a continuous cavity 311 , 321 . The longitudinal reinforcement elements 6 are introduced into the continuous cavities 311 , 321 .

The guide tube 1 with its central opening 11 for the coolant prevents impairment of the downward-hanging region of the shrink tube 3 during the targeted heat application to the loop-like walls 31 , 32 .

If necessary, the Einspannbac can also be used for this purpose ken be provided with appropriate cooling.

FIG. 2 shows the shrink tube 3 partially shrunk back in the area of the wall projections 31 , 32 with the mold jaws 4 serving as additional deformation devices. The right shape of these jaws 4 is shown in the end seat with Conditioning to the associated jaws. 2 In this position, this mold jaw 4 gives the wall protrusion 32 its final shape.

The left mold jaw 4 is shown in the operating position before the displacement in the direction of the arrow toward the wall protrusion 31 . The wall protrusions 31 , 32 of FIG. 2 have shrunk back so far due to the targeted application of heat that the mold jaws 4 only have to bring about the final deformation of the wall protrusions to the desired closure elements.

The wall protrusions 31 , 32 formed to such longitudinal closure elements are closed in a known manner as soon as the shrink tube is placed around the substrate to be coated. Me tall clamps or similar elements can serve as a closure here.

Fig. 3 finally shows that after the separation of the basic body wall between the circumferential thickening form the wall protrusions 31 , 32 obtained end profiles 5th This end profile 5 consists of a still shrinkable with telteil 51 and the subsequent wall projections 31 , 32nd The ver after the separation process on the wall protrusion 31 , longitudinal flap-like strips 52 , which has already shrunk by the partial shrinking process, can serve as additional cover when closing the shrink sleeve.

Claims (8)

1. A method for producing a with a longitudinally the fastener ver on the thickened edges closable shrink sleeve made of polymeric material, in which a base body is extruded, crosslinked, stretched in a crosslinked state and cooled with freezing of the stretching tension, characterized in that at the Base body by partial, longitudinal To summarize wall areas loop-like wall protrusions are generated, which are shrunk back to the outward-pointing circumferential thickening by insulation of the remaining wall by heat application. 2. The method according to claim 1, characterized in that the loop-like wall protrusions each one have continuous cavity. 3. The method according to claim 1, characterized in that the base body is coated on the inside with adhesive the glue through the heat application in the area the wall protrusions is activated, and that at Shrinkage of the excess wall of the adhesive to permanent setting of opposite wall areas the circumferential thickening serves. 4. The method according to claims 1 and 3, characterized net that the peripheral thickening starts from the outside shaping forces until the end of the back shrinking process can be brought into shape.   5. The method according to claim 2, characterized in that into the cavity of the wall protrusions before insertion the targeted heat application reinforcing elements to be brought. 6. The method according to one or more of the preceding An sayings, characterized in that a tubular ger base body is used. 7. The method according to claim 6, characterized in that after completing the shrinking process of the schleifenar wall protrusions of the tubular base body is separated between the circumferential thickenings. 8. The method according to claims 1 to 5, characterized in net that as a basic body a flat, bandför element is used.