The present invention relates to a device for protecting mechanical parts likely
5 to be exposed to a force, friction or vibrations. It applies in particular to the protection
against damage, notably due to the corrosion of supported valves and piping, at the
location of the contact with their support.
PRIOR ART
10 It is known to place, between two mechanical parts intended to be supported
and for which it is desired that corrosion be limited, a half shell made of a composite
material, the surface shape of which is adapted to the shape of one of the parts. For
example, in order to protect a circular-based cylindrical pipe, a half shell of cylindrical
shape, having an internal diameter equal to the external diameter of the pipe, is
15 placed between this pipe and a support.
These half-shell systems present numerous drawbacks. Firstly, they require a
corresponding half shell for each diameter of pipe.
The solution is also known which consists in placing a piece of elastomer or
thermoplastic between the parts on the contact area. However, this material is rapidly
20 crushed and rendered inefficient.
OBJECT OF THE INVENTION
The present invention seeks to overcome some or all of these disadvantages.
The present invention thus relates to a device for protecting against damage,
25 in particular corrosion, a mechanical part bearing on a support, or being under
pressure, notably as a result of weight, such a device comprising a flexible area
designed to be in direct contact with the mechanical part and at least one row of
rectilinear pads designed to be in direct contact with the support, the row of pads
having a plurality of pads rigidly connected to the flexible area and more rigid than
30 the flexible area.
2
Thanks to this device, mechanical protection is placed between these parts by
rigidly connecting the flexible area to one of the parts. The device also absorbs
mechanical vibrations between the protected parts. Thus, the same protective device
may be used for various diameters of pipe, which thus also reduces the storage and
5 warehousing requirements. Moreover, the flexibility of the device, at least in one
direction, reduces the need to level, polish or adjust the surface of the parts. The
device of the present invention thus limits corrosion between the protected parts. The
device of the present invention ensures at least the same protection as a half shell,
without the disadvantages of the latter and has a service life much greater than that
10 of coatings made of elastomeric material. Moreover, devices adapted to different
diameters or part sizes and different mechanical forces to be supported, by different
weights for example, can be easily foreseen. Moreover, this device can be used as a
spacer for the parts that are not arranged close enough together to be supported
directly, for example in the case of a series of supports along a pipe, when one of the
15 supports is at a height lower than that of the two other supports.
In some embodiments, the mechanical part (22) is a pipe.
In some embodiments, the pads are rectangular in shape.
In some embodiments, the pads have a width between 20 mm and 30 mm and
a length between 10 mm and 30 mm.
20 In some embodiments, the interval between two pads is between one-half their
length and one times their width.
In some embodiments, the flexible area comprises at least one woven layer.
Thanks to these features, the device benefits from the homogeneity and
resistance specific to fabrics.
25 In some embodiments, at least a portion of the plurality of pads is made of
plastic material.
Thanks to these features, the pads are very rigid. The plastic material from
which the pads are made ensure electrical, or even thermal, insulation between the
parts. Moreover, the pads thus absorb various vibrations between the parts that they
30 separate.
In some embodiments, at least a portion of the plurality of pads comprises two
combined materials, one of said materials being more flexible than the other.
This combination is, for example, a weave or an overlay. Thanks to each of
these features, these pads have greater vibration and shock absorbing capacity.
3
In some embodiments, the more flexible material is encased by the more rigid
material.
Thanks to these features, the device may be applied to non-cylindrical parts or
pass over surface irregularities on cylindrical parts, such as welds forming bumps on
5 pipes, for example. The device is thus flexible in two orthogonal directions.
In some embodiments, the most rigid material is polyphenylene
sulfide (P.P.S.).
In some embodiments, the flexible area and the pads are formed of the same
homogeneous material.
10 For example, the flexible area and the pads are made from a single and
15
homogeneous block of material. This block, made of a single material, may be
shaped to form the flexible zone and the pads by machining, moulding, injection or
extrusion, for example. For example, the flexible area has a thickness less than or
equal to one millimetre in order to have the necessary flexibility.
BRIEF DESCRIPTION OF DRAWINGS
The advantages, objects and features of the present invention will become
apparent from the following description, provided for explanatory purposes and in a
non-exhaustive manner, when taken in conjunction with the accompanying drawings
20 wherein:
Figure 1 represents, schematically and in cross-section, the embodiment of
the device of the present invention placed between a pipe to be protected and a
support;
Figure 2 represents, schematically and in perspective, the preferred
25 embodiment of the device of the present invention; and
Figures 3, 4 and 5 represent cross sections of pads of various embodiments of
the device of the present invention.
30 DETAILED DESCRIPTION OF THE INVENTION
As illustrated in Figure 1, the protection device 10 according to the invention is
positioned between two parts 20 and 22 for which it is desired to limit corrosion, wear
or vibration. For example, part 20 is a support placed in a platform or on the seabed
and part 22 is a pipe.
4
The device 10 comprises a flexible zone 12 and, rigidly connected to the
flexible area 12, a plurality of rows of pads 14 more rigid than the flexible area.
As seen in Figure 1, the part 22, here shown as piping such a pipeline, is
supported on a single row of pads, such that the bearing surface of the piping on the
5 support 20 is as large as possible. However, the other rows of pads on either side
are necessary to the extent that, in case of deterioration of the bearing row, these
rows will be useful in always ensuring that the pipe is supported.
Figure 2 illustrates an embodiment 10 of the device for protecting mechanical
parts of the present invention having a flexible zone 12 and several rows of pads 14
10 more rigid than the flexible area, each row of pads being comprised of several pads,
such as pads 14-1, 14-2 and 14-3, for example.
Although a one-piece pad may be used within the scope of the invention,
dividing each row of pads into several pads is very useful. The surface of the
piping 22 degrades over time. Consequently, recesses form on the outer surface of
15 the piping where the metal has left and bumps form as a result of oxidation. As the
piping is no longer rectilinear, having a plurality of pads allows the row to
compensate for the surface irregularities of the piping over time.
According to particular embodiments of the invention, the pads, such as
pads 14-1, 14-2, 14-3 illustrated in Figure 2, are rectangular and particularly square
20 in shape. Preferably, the pads are between 5 mm and 10 mm thick, 20 mm to 30 mm
wide and 10 mm to 30 mm long. The interval between two pads may be between
one-half of their length and one times their width. Thus, with pads measuring 30 mm
in length, the interval between two pads will be between 15 mm and 30 mm.
It should be noted that the height of the pads and the spacing between each
25 pad are such that the piping 22 shall in no case touch the support through the flexible
area.
The flexibility of the flexible area allows relative movement between the pads
and permits the entire device 10 to run along.the surface of a mechanical part to be
protected.
30 The flexible area 12 can be made of elastic material. Preferably, the flexible
area 12 comprises at least one woven layer. A woven layer has the advantage of
possessing a high degree of homogeneity and fabric-specific resistance.
The pads 14-1, 14-2, 14-3 are rigid without being brittle. Preferably, the pads
comprise a plastic material, and/or a non-ferrous metal, such as bronze for example.
5
Their rigidity is thus very high. The plastic material provides electrical, and even
thermal insulation and absorbs various vibrations between the parts. Non-ferrous
metal, such as bronze for example, is not subject to corrosion.
Advantageously, each pad comprises a plastic or resinous material loaded
5 with material designed to limit abrasion. Thus, the friction resistance of the pad is
improved by the material filler adapted to limit abrasion. The pads are progressively
polished, which promotes the sliding of the pipe on the support. Advantageously,
each pad is obtained through pultrusion, extrusion, multi-extrusion or injection. The
pads are thus easily produced, notably with a wall cross-section of various
10 thicknesses so as to create various cross-sections and it is possible to use, in the
same cross-section, different materials that are, for example, rigid to prevent
abrasion and flexible to absorb vibrations.
To manufacture the device 10, the flexible area 12 may comprise a mesh,
braid or weave, which is placed into contact with each pad 14 during a moulding step
15 of each pad 14. In other manufaCturing methods, each pad 14 is secured to the
flexible area while still liquid so that the flexible area 12 penetrates the material of the
pad 14. The pad 14 and the flexible area 12 are thus particularly well-bonded.
In some embodiments, the flexible area 12 and the pads 14 are made of the
same material, as illustrated in Figure 3. This block, made of a single material, may
20 be shaped to form the flexible zone and the pads by machining, moulding, injection
or extrusion, for example. These embodiments have the advantage of being very
inexpensive to manufacture, owing to their manufacturing method, notably when
extrusion or pultrusion methods are used.
In some embodiments, each pad 14 is bonded or welded to the flexible
25 area 12.
In some embodiments, as illustrated in figures 4 and 5, the pad is made of two
materials, one of which encompasses the other to ensure better contact with the
parts to be protected and to improve the vibration and shock absorbing capacity.
Preferably, the more flexible material 30, such as rubber for example, is encased in
30 the more rigid material 32, such as polyphenylene sulfide (P.P.S.), for example.
Preferably, during the manufacture of the device 10, a strip of material is
produced which is wound into coil. The device 10 is then obtained by cutting off the
strip thus manufactured to the dimensions corresponding to the piping and the
support to be protected.
6
In order to implement the device of the present invention, the following
process is applied in order to protect a pipe 22 resting on a support 20:
- a step in which a roll of material, described above, is cut between two pads
to form a protective device 10. The size of the protective device 10 depends on the
5 parts to be protected. The thickness and the length of the pads 14 depend on the
pressure exerted by the piping and expected slippages. Two or three types of pads
are considered in order to meet all the requirements for piping ranging in diameter
from two to fifty-six inches (approx. 5 to 140 em).
-a step of raising the pipe 22, according to known techniques,
I 0 - a surface preparation step of at least one said part, of pipe 22 for example,
by shotpeening and degreasing for example,
- a step of impregnating the prepared surface and/or the flexible area 12 of the
device 10, for example with adhesive, of polymerisable resin for example, configured
to harden under the effect of radiation, heat or a chemical reaction between
15 components,
- a positioning step in a manner such that at least the entire contact surface of
one of the pads is parallel to the face of the support intended to receive the pipe, and
- a pressing step of the area 12 on the adhesive and on the surface of the
prepared part, by banding with at least one tight strap, for example, around the
20 device 10 and pipe 22 that it supports. The adhesive then hardens, thereby bonding
the device 10 to the pipe 22.
Of course, the two surfaces in contact may be subject to separate protection.
- a step for installing the pipe 22, according to known techniques
As can be understood from reading the description above, by joining the
25 flexible area to one of the parts, mechanical protection is achieved between the parts
to be protected. The device of the invention also absorbs mechanical vibrations
between the protected parts. In addition, the same protective device may be used for
different pipe diameters, which thus also reduces the storage and warehousing
requirements.
30 The flexibility of the device, at least in one direction, limits the need for surface
treatment of the parts. The device of the present invention thus limits corrosion
between the protected parts. In addition, devices can easily be provided which are
adapted to different diameters or sizes of parts to be protected.
7
The device of the present invention does not apply only to pipes. It applies in
all cases where mechanical parts are in contact and at least one of these parts
requires protection from corrosion, vibration, impact, or reaction with a material
comprising the other part, for example.

CLAIMS
1. A device (1 0) for protecting against damage, in particular corrosion, a mechanical
part (20) bearing on a support (22), or being under pressure as a result of weight;
the device being characterized in that it comprises:
5 -a flexible area (12) designed to be in direct contact with the mechanical part
10
and
-at least one row of rectilinear pads (14) designed to be in direct contact with
the support, said row comprising a plurality of pads (14-1, 14-2, 14-3) rigidly
connected to said flexible area and more rigid than said flexible area.
2. The protective device (1 0) according to claim 1, wherein said mechanical part (22)
is a pipe.
3. The protective device (10) according to claim 1 or 2, wherein said pads (14-1, 14-
15 2, 14-3) are rectangular in shape.
20
4. The protective device (10) according to claim 3, wherein said pads (14-1, 14-2, 14-
3) have a width between 20 mm and 30 mm and a length between 10 mm and
30mm.
5. The protective device (10) according to claim 3 or 4, wherein the interval between
two of said pads (14-1, 14-2, 14-3) is between one-half of their length and one times
their width.
25 6. The protective device (10) according to claims 1 to 5 wherein said flexible
area (12) comprises at least one woven layer.
30
7. The protective device (10) according to claims 1 to 6, wherein at least a portion of
said pads (14-1, 14-2, 14-3) consists of plastic material.
8. The protective device (10) according to any one of claims 1 to 5, wherein at least a
portion of the plurality of pads (14) comprises two combined materials, one of said
' materials being more flexible than the other.
5 9. The protective device (10) according to claim 8, wherein the more flexible material
is encased by the more rigid material.
10. The protective device (10) according to claim 9, wherein the more rigid material is
polyphenylene sulfide (P.P.S.).
11. The protective device (1 0) according to claims 1 to 5, wherein said flexible
area (12) and said pads (14-1, 14-2, 14-3) are formed from the same homogeneous
material.