FR2658582A1 - Tubes and pipes with moulded internal walls - Google Patents

Abstract

The present invention relates to a tube, or a pipe, exhibiting, on its internal wall (2), fluting, mouldings (1), elongate elements with constant profile, hollow or projecting, square or round, straight or curved; often helical (Fig. 1). Amongst its advantages, the invention saves on the quantity of raw material whilst improving the strength of the walls, rigidifies the tube or promotes bending thereof, avoiding its bore (3) flattening, increases the contact surface between the internal wall and the fluid which runs through the pipe, thus promoting heat exchanges. This invention applies particularly to rigid or flexible extruded tubes and pipes; particularly to plumbing, sheaths and hoses.

Description

There are many tubes and pipes, of different shapes and colors, and their walls are often smooth. Some have ringed folds, making them flexible. some have a composite wall. Some tubes are hollow threaded rods
Tubes and pipes are often extruded. The speeds of extrusion of the tube, rotation of the mandrel, of cylindrical parts having asperities, irregularities, lugs, moldings and the inclination of the drawing bench determine, among other things, the inventive characteristics of this new tube.

The present invention relates to elements which are added to the walls of the tube to give it a certain character. It relates to elongated elements with a constant hollow or raised profile. We will call these elements gadroons, moldings.

These moldings have protruding, hollow, square or round, straight or curved profiles. The same profile can associate several simple forms. Let us quote for the hollows, for example, the grooves, the grooves, the grooves, the grooves, the cavets; and for projections, for example, baguettes, sausages, listels, squares.

Compound shapes are possible, such as a square and a round, a square and a flat forming a T or an L for example. The same internal wall may have moldings of different natures. These moldings can have a variable arrangement relative to the long axis of the tube. Two arrangements have many applications: -The moldings parallel to this axis -The moldings arranged in a helix around this axis -Let's moldings transverse to this axis.

Their number is variable. They are often placed at regular intervals on the walls.

The advantages of such an invention are manifold. They depend on the shape, the arrangement, the number of moldings, characteristics adapted to the use of the tube, the pipe.

Let us cite, for example, the following advantages: 1- Modify the rigidity of the tube
Rods arranged on the internal walls, parallel to the long axis of the tube increase its rigidity, its resistance to its longitudinal bending. Rods arranged in a helix prevent the tube from being bent when its tube is bent.

2- Reduce the quantity of raw material the molded walls are lighter, with increased mechanical resistance. This is interesting if the raw material is expensive or if the tube must be as light as possible.

3- Being easy to bend
Helical moldings define or delimit zones of grinding thickness which facilitate the bending of the tube, and zones of greater thickness which avoid the flattening of the lumen of the tube. The average thickness of the molded wall of the tube is often smaller compared to the thickness of a traditional smooth-walled tube.

4- Give a fluid an optimal movement
Large helical moldings create a vortex, moldings parallel to the long axis of the tube give the fluid a linear movement.

5- Increase the contact surface between the contents of the tube and its internal wall
This can be interesting during thermal or chemical exchange.

6- Increase the friction of the fluid on the tube, increase the pressure drop of a fluid, of an exhaust gas.

7- Increase the deposit of elements contained in the fluid of the tube 8- Easily create multiple jets of fluid if we add, for example, a full cylinder in the molded lumen of the tube 9- Avoid a brutal bursting of the tube if it exists a very high pressure in the tube, its bursting occurs more gradually due to its irregular structure.

10- Center an object in the lumen of the tube, the latter having to be surrounded in a homogeneous manner with fluid, or even for mechanical reasons by reducing friction, for example, the object touching only a small part of the wall.

11- temporarily decrease the diameter of the tube by rotation or by bending
Specific aspects
The profiles of the moldings can be inconsistent, variable, periodic, interrupted in certain places to allow, for example, better rigidity or better bending.

The moldings are in principle produced at the same time as the tube itself. There is nothing to prevent them from being secondary, for example, by pleating, by abrasion, by turning, by adding elements.

The tube can be formed from composite elements.

The ends of the tube can be modified thanks, for example, to a stamper taking into account the moldings,
For exemple
It was designed for plumbing, a copper tube with relief moldings, helical, on the inner face of the wall.

These moldings are rods which perpendicularly reinforce the wall. Such a tube is 20g lighter than a traditional tube, which represents a considerable saving. The outer wall is smooth, therefore the welds and connections are easy
Another example concerns heating or refrigeration. the moldings of this new tube penetrate more the fluid which traverses its light, of this fact the heat exchanges are faster.

 Plastic hoses with molded walls are more flexible, lighter and less easily crushed.

This invention relates to tubes, pipes, rods, conduits, rigid or flexible, metallic or not, glass, plastic, rubber or the like; and particularly extruded tubes, seems to have very wide applications.

The moldings modify the mechanical resistance and the flexibility of the tubes.

Claims (8)

1- tube, flexible or rigid pipe, characterized in that its internal walls (2) have gadroons, moldings (1), that is to say elongated hollow or projecting elements, with constant profile; parallel, perpendicular or helical to the long axis of the tube. 2- Tube according to claim 1, characterized in that the moldings of its walls have an inconsistent, variable, periodic profile, that the moldings can be interrupted on certain segments of the tube. 3- moldings, according to claims 1 or 2, characterized in that their profile has simple shapes, square or round, straight or curved; or composite forms of these. 4- Tube characterized in that its helical moldings avoid the flattening of its light during bending, the bending of the tube 5- Tube characterized in that its internal moldings, parallel to the major axis increase its rigidity.  6- Tube characterized in that its internal moldings increase its internal surface and promote exchanges between the tube and its content. 7- Tube according to claims 1 or 2, characterized in that the parallel or helical moldings of the internal wall impart a linear movement or turning to a fluid passing through its light and possibly exiting at its end. 8- Tube according to claim 1, characterized in that the moldings promote the centering of a luminal object. 9- Tube according to claim 1, characterized in that the moldings strengthen the wall and allow the use of less c raw materials e