The present invention relates to a profiled member which is designed to be glued on another profiled member which is designed in particular to provide reinforcements of wind turbine blades, wind turbine blades, or laminar/glued beams which are used for example in civil engineering, and the production process thereof.
The gluing of these two profiled members to one another can for example be used to produce reinforcements as described in patent EP2497945.
In order to facilitate the gluing of the profiled members to one another, a peelply (or peel ply) is provided, which is also known as tear or delamination fabric by persons skilled in the art, on at least one of its two faces, and which strip will be removed before the profiled members are glued. This peelply makes it possible to obtain a surface of the profiled member which is both neat and sufficiently rough to facilitate the coupling of the two profiled members to one another.
This peelply can be put into place during the process of production of the profiled member, but it is then found that a rim is formed on the profiled member on the periphery of the peelply.
When the peelply is removed, this rim will remain in relief on the side of the profiled member, and will firstly prevent optimum contact between the profiled member and the one on which it must be glued, and secondly, during tearing away in cold conditions, it will occasionally give rise to tearing of the peelply, and/or leave residual fibers on the profiled member, thus impeding its gluing. An additional cleaning operation must then be carried out in order to finalize the preparation for gluing of the profiled member. There is also the possibility of covering of the peelply by carbon fibers and/or matrix in the process, and this covering embeds the edges of the strip, which can thus increase significantly the probability of giving rise to tearing or residual fibers as described above.
Although the removal of the peelply is relatively easy when it is made of polyamide (PA) and/or when the profiled member is made of carbon-vinylester, it can be particularly difficult if a thermoplastic such as polyester (PES) is used in the place of the PA for a peelply with a profiled member made of carbon/epoxide.
It is possible to carry out surface abrasion instead of and in the place of the peelply, but there is then the presence of dust which requires cleaning with solvent before application of the glue.
It is also possible to carry out surface preparation which is not mechanical, but only chemical (primer or cold plasma, etc.), which leads to an increased risk of fatigue fracture of the gluing, since the surface of the profiled member remains substantially flat.
It is additionally possible to use an anti-adhesion agent placed below the peelply, but this agent detracts from the adhesion of the faces to be glued.
It is known to use a film below the corner or the edge of a connection layer in order to facilitate its tearing away and the formation of a fissure on the surface of the compound, but this film represents an additional cost for the production of the profiled member.
It is additionally known to turn back the edge of the peelply in order to obtain a grip, however this solution is not satisfactory since it requires a peelply which is larger than the surface of the profiled member, it is more difficult to put into place, and is thus more costly to implement.
The objective of the invention is to propose a process for production of a profiled member with a peelply which does not have these disadvantages, and to propose the profiled member obtained.
The invention relates to a process for production of a profiled member, and is characterized in that it comprises a step of adhering a peelply, and a step of unsticking at least one edge of the peelply, in that the profiled member is pultruded, and in that the step of unsticking is carried out at the output from the die. The profiled member obtained is thus easier to use. During standard pultrusion steps, there is impregnation, drying and polymerization in a die. According to the invention, the unsticking starts to be carried out in the manufacturing line by blades at the output from the die, when the product is still at a suitable temperature at the end of polymerization, the protruded product is drawn and wound along the length of the flat parts with the peelplies prepared for tearing away along all or part of the profiled member. The profiled member obtained has two faces with at least one peelply with two edges disposed and glued on a face of said profiled member, and the peelply of which has at least one edge which is unstuck. The edge thus unstuck makes it possible to grip the peelply easily by hand, and remove it more easily, as well as to prevent an end of the peelply remaining on the profiled member and impeding the gluing of the profiled members to one another. The two edges of the peelply can be unstuck, and, when the profiled member is covered by a peelply on each face, the two peelplies are each unstuck at one side at least. The profiled member can have a flat or circular form. In addition, since the profiled member is made of a pultruded composite material, it has high-level transverse mechanical performance, and in particular a profile made of carbon/epoxide has high mechanical performance levels perpendicular to the preferential direction of the reinforcement fibers which are up to 5 times better than those of a profiled member made of carbon/vinylester.
Advantageously, the step of unsticking is carried out by a blade. This blade can be disposed at the end of the process of production of the profiled member, and can thus be automated. This makes possible a saving in labor and elimination of the finishing operations. The parts can have any form and cross-section which can be produced by pultrusion.
Advantageously, the step of unsticking is carried out in hot conditions. Hot preparation of the peelply makes it possible to reduce the constraints of coupling of the strip on the profiled member. Ideally, the temperature should be close to the vitreous transition temperature Tg of the matrix of the compound, for example a minimum temperature of 20° C. below the Tg.
Preferably, the unsticking in hot conditions can be carried out during the polymerization process, in order to benefit from incomplete resistance of the matrix, and thus facilitate the unsticking.
Advantageously, the blade has an inclination relative to the plane of the profiled member. It is thus certain that no rim remains on the profiled member.
Advantageously, the blade is aligned with the plane of the profiled member. The profiled member thus has a globally flat surface.
Advantageously, the profiled member and the peelply are machined at the second edge of the peelply. This machine makes it possible to eliminate the rim which appears on the profiled member, and thus permit the contact of the profiled member over all of the surface corresponding to the peelply. It is possible for both edges to be machined, and there is then no unsticking of the peelply. The machining can be partial or total.
Advantageously, a side of the profiled member is covered with a veil at the second edge of the peelply, and said veil is placed below the edge of said peelply. The veil disposed on the side of the profiled member makes it possible to prevent possible covering of the peelply by carbon fibers and/or matrix which is formed in the process. Both edges of the profiled member can be covered with a veil. There is then no unsticking of the peelply.
According to a particular arrangement, at least one edge of the peelply is turned back. When thus turned back, the peelply prevents any insertion in the rim of the profiled member. The turned-back edge can easily be released. It is possible for all the edges of the peelply to be turned back.
The invention also relates to a profiled member with two faces having at least one peelply with two edges disposed and glued on a side of said profiled member, and characterized in that it is produced by the process having at least one of the preceding characteristics.
The invention also relates to an assembly comprising at least two profiled members with at least one of the preceding characteristics, and characterized in that the two profiled members are glued to one another. It is also possible to glue the profiled member on other types of surfaces such as concrete, steel, etc.
Other advantages may also become apparent to persons skilled in the art from reading the examples below, illustrated by the appended figures, and provided by way of example:
The profiled member 1 according to the prior art, illustrated in
The profiled member according to the invention, illustrated in
In
A description will now be provided of a preferred process for production of these profiled members.
The profiled member 1 is produced according to a process with a first standard molding or pultrusion part, with putting into place of at least one peelply 2, then the profiled member 1, still hot at the end of polymerization, passes in front of the blades (4, 40, 41) where at least one edge 20 of the peelply 2 is unstuck.
For the pultruded profiled members, there is impregnation of the fibers, drying, putting into place of the peelplies, then polymerization in the die, a start of unsticking of the peelply in the manufacturing line by the blades at the output from the die when the product is still at the appropriate temperature at the end of polymerization, traction of the pultruded profiled member, and winding along the flat parts with the peelplies started over all or part of the profiled member.
It can be envisaged to carry out the tearing away in cold conditions, although this is more complex to carry out since the adhesion and embedding of the strip on the die are greater, in particular for a PES strip on a profiled member made of carbon/epoxide.
It is also possible to carry out the tearing away in hot conditions outside the process of production of the profiled member. It is then necessary to carry out an additional step of heating of the profiled member at the moment of tearing away of the strip, either in line before the gluing of the profiled members to one another, or as reworking in the other cases.
Number | Date | Country | Kind |
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1662359 | Dec 2016 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/FR2017/053180 | 11/20/2017 | WO | 00 |