Patent Description:
Insulation in air conditioning, cool installations, process installation, and heating installation has become more important over the years.

In this respect, thermal insulation relates to a reduction of heat transfer between objects in thermal contact or in range of radiation influence, such as tubing in a maintenance room. Thermal insulation can be achieved with suitable object shapes and materials. The heat transfer (flow) is considered as an inevitable consequence of contact between objects of differing temperature. In order to reduce heat flow, and thus maintaining an object substantially at a same temperature, a thermal insulation is provided. The thermal insulation has a reduced thermal conduction or likewise an insulating action. A thermal conductivity (k) is used to quantify insulating properties. Therein a low thermal conductivity value indicates a high insulating capability (R-value). Other important properties of insulating materials are product density (ρ) and specific heat capacity (c). It is noted that cooling requires much more energy than heating; so maintaining a low temperature is in view of energy consumption quite important.

Heating and cooling systems are sources of heat. They distribute heat through buildings, typically by means of pipe or ductwork. In order to reduce energy consumption insulating these pipes using pipe insulation in unoccupied rooms is required. It further prevents condensation occurring on cold and chilled pipework. Preventing the formation of condensation on pipework is important as moisture contributes to corrosion.

Likewise chemicals, water, air, electrical cables, can run through pipe work.

An example of a document relating to isolation is <CIT> which recites a pipe insulating fitting cover for insulating a pipe j oint, the cover having a first insulating cover for insulating the body of the pipe joint and a second insulating cover for enclosing and insulating the bonnet of the pipe joint. The application recites use of an abrasion apparatus. As a result thereof parts of said cover are abraded to obtain a specific shape. Such abrasion requires a rigid insulation material and a substantial chance of burr formation at the edge of abraded regions. In addition no good insulation is obtained at the edges. It is noted that a curvature of the abrasion apparatus limits the application to specific pipe diameters. Shaping an insulation cover using an abrasive would result in burr formation and an uneven sealing of both the insulation cover itself and the to-be-covered material. The covers used are curved.

For (somewhat) complex piping insulation typically flexible elastomeric foams are used. These foams relate to flexible and closed-cell structures. Examples are rubber foams based on NBR or EPDM rubber. Flexible elastomeric foams exhibit such a high resistance to the passage of water vapor that they do not generally require additional water-vapor barriers. Such high vapor resistance, combined with the high surface emissivity of rubber, allows flexible elastomeric foams to prevent surface condensation formation with comparatively small thicknesses.

As a result, flexible elastomeric foams are widely used on refrigeration and air-conditioning pipework. Flexible elastomeric foams are also used on heating and hot-water systems. However these flexible foams still have to be applied on the structures. Such includes cutting and gluing of parts. If long stretched piping is involved, such cutting and gluing is relatively simple. For complex structures, such as bends, couplings, flanges, T-junctions, and butterfly valves, craftsmanship is required. It is especially relevant that insulation pieces and parts fit well together in order to prevent condensation, mold growth, microbial growth and corrosion. For durability, fire safety, noise reduction and appearance it is important that no burrs are present. Cutting should be performed with relatively high precision and without forming burrs.

Complex structures, such as pipe-couplings, passages through walls and floors, bends, bifurcations, sensors, T-junctions, controllers, closures, vents, locking wheels, supports, suspensions, (butterfly)valves, flanges and branches, are especially difficult to insulate. In order to reduce noise and to improve fire safety similar considerations as above apply.

Thermal insulation is typically applied to a <NUM>-D structure by using an adhesive. Despite great care, often the thermal insulation does not adhere sufficiently to the 3D-structure. Also labor conditions at the site of installation are often at least somewhat difficult, e.g. in terms of limited space, availability of tools, environmental conditions, etc. In view thereof an improved method of insulation may be referred to. <CIT> recites a method of insulting complex <NUM>-dimensional structures.

Some background art may be referred to. <CIT> recites a method for filling a gap in the coating of a pipeline coated with a coating, in particular a thermo-insulating coating. The method comprises the steps of placing in the gap a mixture of solid elements and a thermoplastic polymeric material in fluid state, and letting the thermoplastic polymeric material in fluid state solidify. <CIT> recites an apparatus, such as pipelines and associated equipment and to a method of making, insulating, providing buoyancy to, recovering and installing submarine apparatus. The marine or submarine apparatus comprises an impermeable enclosure associated with the apparatus, which enclosure is tightly packed with hollow microspheres to a density where, when submerged in use, the internal pressure of the microspheres is greater than or substantially equal to the water pressure on the apparatus.

It has now been found that even with improved insulation specifically complex <NUM>-D structures are prone to oxidation. A method to prevent such is by providing a coating to said structure, such as a paint. Even though a coating is provided oxidation of underlying material may still occur, in particular when water-based coatings are used.

The present invention therefore relates to an improved method for insulating and products obtained thereby of complex <NUM>-D structures, which overcomes one or more of the above disadvantages, without jeopardizing functionality and advantages.

The present invention relates in a first aspect to an improved method for applying a thermal insulation on a <NUM>-dimensional structure according to claim <NUM>, and in a second aspect to a <NUM>-dimensional product according to claim <NUM>. The three dimensional structure comprises at least two individual tube sections and an outward extending connecting section.

<CIT> recites a method of insulting complex <NUM>-dimensional structures. The document and its contents are incorporated by reference. It is noted that insulation still largely relates to applying pieces of insulation material by hand. Such is especially the case for large ductworks, having external diameters ranging from <NUM> - <NUM> (similar to DN15 to DN2000, such as DN20, DN50, DN80, DN100, DN200, DN250, etc.), typically being used for transport of fluids, like hot and cold water, and gases, like nitrogen and air. Modern ductwork may involve multitudes of <NUM>-<NUM> meters or more for a building or building complex. For understanding in a typical day <NUM> of ductwork may be isolated, whereas such an isolation may continue for months. The ductwork is typically formed from a metal, such as stainless steel, aluminum, or from plastics. The <NUM>-dimensional ductwork typically comprises appendages, such as butterfly valves, pipe-couplings, passages through walls and floors, bifurcations, sensors, controllers, closures, vents, locking wheels, supports, suspensions, flanges and branches. Especially insulation of non-straight elements is subject of the present invention. These non-straight sections, after being insulated by the present flat insulation material, are left with hollow spaces in between the insulation material and said section, such as a valve. Despite the insulation it is found that especially the parts of the <NUM>-dimensional ductwork not being in direct contact with the insulation material, but with the hollow space instead, are prone to oxidation. This is considered due amongst others to water or water vapor penetrating through the insulation.

The present method makes use of a panel of substantially flat insulation material, such as a foam plate. Preferably the material of the foam plate has an inbuilt, water vapor barrier. The plate is preferably effective in preventing moisture ingress and maintaining a long term thermal efficiency. Preferably a dust and fiber free material is used. Also the material does not rapidly deteriorate and keeps moisture as far from the pipe surface as possible, thereby reducing a risk of expensive under insulation corrosion. The material preferably has a closed cell structure, preferably interconnected closed cells. As such water ingress is limited. The material may vary somewhat in characteristics, e.g. when applied to hot or cold pipe work. In addition the present invention makes use of milled or grinded insulation material, in particular of left-over pieces of such material. In a rough estimate <NUM>-<NUM>% of the material is left over during insulation, and the present invention is therefore considered rather cyclic in terms of re-use of material. Parts of the 3D structure to be isolated may be provided with a protecting layer, in particular the parts to be covered by particles of insulation material. Suited protecting materials are jelly-like materials, such as petroleum jelly, in particular purified jelly, or likewise a jelly with a low alkaline or acid content, such as white vaseline.

The present flat insulation material has a thickness of <NUM>-<NUM>, such as <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM>. The insulation material may have an adhesive layer. The thickness of the material is selected in view of insulation properties and temperature gradient between liquid (gas/fluid) in e.g. ductwork and outside temperature.

In a next step one or more <NUM>-dimensional elements from the flat insulation material are formed, typically by hand. In the context of the present invention such an element is referred to as a two-dimensional element as the element forming substantially has a two dimensional shape or form, such as a square or rectangular form, circle section ellipsoid section, a shape according to <FIG> or <FIG>, etc. The element clearly has the thickness of the insulation material and in that sense it is a three-dimensional element. The one or more <NUM>-dimensional elements together are intended to form a closed structure around the pipe work, or part thereof. As such the elements need to fit perfectly with respect to one and another. It is noted that often, despite standardized measures of pipe work, most of the work is done on location, that is where the pipe work is present.

In a next step the one or more <NUM>-dimensional elements are applied on the <NUM>-dimensional structure. The one or more <NUM>-dimensional elements are typically fixed by applying an adhesive.

The method of insulation is characterized e.g. in that in addition to the above flat insulation material also particles of insulation material are provided. The present method comprises providing an enclosure <NUM>, the enclosure comprising at least one input opening 1a for providing a flow of insulation material, and at least one output opening 1b for releasing gas, in particular air, at least one input opening 1a and at least one output opening 1b being in fluidic connection with one and another, wrapping the enclosure <NUM> around an appendage <NUM> of the <NUM>-dimensional structure, providing thermal insulation material, wherein the thermal insulation material comprises individual particles <NUM> with a particle size of <NUM>-<NUM>, in particular <NUM>-<NUM>, providing the particles of insulation material in the enclosure, substantially filling the enclosure, and providing flat thermal insulation material <NUM> to the appendage including the enclosure.

In addition to the above, the present method may comprise providing a first layer of adhesive on the thermal insulation material, wherein the first layer may be applied partially on the surface of the insulation material, or fully, typically depending on the joints to be formed, as well as on the size of sub-elements of the 3D-structure, pre-drying the first layer of adhesive during a time at a pre-drying-temperature, typically at ambient conditions, such as for at least one hour, preferably for at least <NUM> hours, more preferably for at least <NUM> hours, and typically at least <NUM> hours, at ambient workshop temperature, and applying the thermal insulation on the <NUM>-dimensional structure, optionally after fully or partly abrading and/or polishing the 3D-structure, preferably with sand paper or emery paper. After pre-drying the adhesive has lost most or all of its initial tackiness, and can therefore be applied without the thermal insulation material being adhered to the 3D structure. It is noted that some insulation materials may be provided already with adhesive, and a thin layer of paper or plastic or the like to protect the adhesive before being used, but these adhesive often do not adhere properly, or not fully, or let go over time. Surprisingly, by pre-drying the present adhesive, and thereafter heating the adhesive the adhesive strength is increased significantly and none of the above problems occur. In addition also slits, at joints where two sides of the insulation material come together, are absent. Such does not only improve thermal insulation, but also prevents water/moisture from entering, <NUM>-D structure from being deteriorated, and further provides aesthetically very pleasant insulations.

Thereby the present invention provides a solution to one or more of the above mentioned problems and drawbacks, without jeopardizing beneficial effects. Advantages of the present description are detailed throughout the description.

The present invention relates in a first aspect to an improved method for applying a thermal insulation on a <NUM>-dimensional structure according to claim <NUM>. The <NUM>-dimensional structure typically relates to elements of ductwork and piping, such as pipe-couplings, passages through walls and floors, bends, bifurcations, sensors, T-junctions, controllers, closures, vents, locking wheels, supports, suspensions, (butterfly)valves, flanges and branches. The outward extending connecting section may also relate to a sensor, a controller, a closure, etc.; the term indicates such extensions in general.

In an exemplary embodiment of the present method the particles are provided under pressure, in particular a pressure of <NUM>-<NUM> kPa, more in particular <NUM>-<NUM> kPa. In particular a pump or the like may be used, providing an over-pressure, or likewise, an under pressure when particles are sucked through. In view of water content, an air pressure is relatively high, in order to minimize water content; in particular the initial pressure is relatively high, such as the pressure provided by a pressure delivering device.

In an exemplary embodiment of the present method the enclosure is made of a flexible material, in particular from a polymeric material, more in particular from ABS, PP, PE, and PVC.

In an exemplary embodiment of the present method enclosure typically has a limited thickness, such as from <NUM>-<NUM>, in particular <NUM>-<NUM>.

In an exemplary embodiment of the present method the enclosure is substantially transparent. Therewith a user may easily observe if the space between the enclosure and the appendage is sufficiently filled with particles.

In an exemplary embodiment of the present method the at least one output opening (1b) comprises a mesh, in particular a mesh with openings smaller than <NUM> in cross-section, more in particular < <NUM>. As such no particles pass through, but air can pass through without much problem.

In an exemplary embodiment of the present method the particles are obtained from waste thermal insulation material, wherein the waste thermal insulation material is milled or grinded. Therewith waste material can be re-used, and spillage is reduced significantly, especial in case wherein appendages form a significant part of the <NUM>-d structure.

In an exemplary embodiment of the present method the <NUM>-D structure comprises a plurality of sub-elements, in particular wherein sub-elements are selected from the group of straight sections, from bends, from couplings, from T-junctions, from butterfly valves, from pipe-couplings, from passages through walls and floors, from bifurcations, from sensors, from controllers, from closures, from vents, from locking wheels, from supports, from suspensions, and from flanges and branches. Hence relatively complex structures can be insulated.

In an exemplary embodiment of the present method the flat thermal insulation material is applied by providing a first layer of adhesive on the thermal insulation material, pre-drying the first layer of adhesive during a pre-drying time, applying the thermal insulation on the enclosure and/or <NUM>-dimensional structure, and heating the first layer of adhesive during a first period of time at a first heating-temperature.

In an exemplary embodiment the present method comprises providing a second layer of adhesive on the <NUM>-dimensional structure, and drying the second layer of adhesive during a second period of time at a second drying-temperature. The second layer may be a one-component adhesive as well. The second layer may improve adhering. Generally the second layer is not required, and a first layer only is found to be sufficient for good adhering. However when a size or diameter of the <NUM>-dimensiaonl structure becomes larger, such as larger than a diameter of <NUM>, it is preferred to also apply the second layer of adhesive.

In an exemplary embodiment of the present method the first period of time may be < <NUM> seconds, such as <NUM>-<NUM> seconds, such as <NUM>-<NUM> seconds, i.e. the adhesive heats and dries relative quickly and provides extra adherence.

In an exemplary embodiment of the present method the first heating-temperature may be < <NUM> (<NUM>), such as <NUM>-<NUM> (<NUM>-<NUM>). The drying temperature is preferably not too high, in view of the insulation material, and is preferably high enough to establish drying. Slightly elevated temperatures suffice.

In an exemplary embodiment of the present method the second period of time may be at least one hour, preferably for at least <NUM> hours, more preferably for at least <NUM> hours, and typically at least <NUM> hours.

In an exemplary embodiment of the present method the second drying-temperature may be < <NUM> (<NUM>), such as <NUM>-<NUM> (<NUM>-<NUM>), and typically is at ambient conditions.

In an exemplary embodiment of the present method heating may be under application of a heated air flow, such as using a blow dryer. Heating can simply be established by using a conventional blow dryer.

In an exemplary embodiment of the present method heating may be under application of induction. An advantage thereof is that the insulation material itself does not heat up. In addition no vapor, such as emitted is released from the adhesive.

In an exemplary embodiment of the present method heating may be under application of microwaves.

Heating may be applied with an apparatus providing a power of <NUM>-<NUM> kW, such as <NUM>-<NUM> kW, typically applied over a surface area of <NUM>-<NUM><NUM>. If microwave or induction is used suitable frequencies are <NUM>-<NUM>, such as <NUM>-<NUM>.

Typically all forms of heating do not damage the insulation material.

In an exemplary embodiment the present method may comprise drying the applied thermal insulation during a period of > <NUM> minutes, such as > <NUM> minutes, e.g. > <NUM> minutes. Drying of the adhesive typically consumes some time.

In an exemplary embodiment of the present method providing a first layer of adhesive and pre-drying the first layer of adhesive may be done at a first location, and wherein applying the thermal insulation on the <NUM>-dimensional structure may be done at a second location. The present method provides the opportunity to prepare for application of an insulation material at a location different to where the insulation material is applied, such as at a workshop or workplace. At such a workshop conditions are typically much more optimal in view of preparation, such as space, ventilation, temperature, humidity, and so on. Also for forming the substantially 2D-structures equipment is typically available, and well accessible. A worker may for instance prepare a large number of insulation pieces, such as <NUM>-<NUM> pieces, then move to the location of application, and apply the pieces. The process-time is thereby reduced by <NUM>-<NUM>%, whereas also the quality is improved, e.g. in terms of adhesive strength (being virtually impossible to remove the insulation material), preciseness, joints, appearance, etc..

In an exemplary embodiment of the present method the three dimensional structure may comprise at least two individual tube sections and an outward extending connecting section. The present method is therewith versatile.

In an exemplary embodiment of the present method the thermal insulation may have a thickness of <NUM>-<NUM>.

In an exemplary embodiment of the present method the thermal insulation may comprise a substantially flat panel.

In an exemplary embodiment the present method may comprise forming one or more substantially <NUM>-dimensional elements from the flat insulation material, wherein forming is assisted by a motor that provides reciprocating motion to a cutting element.

In an exemplary embodiment of the present method the forming may be performed at a constant angle with respect to the <NUM>-dimensional element, wherein the angle is preferably selected from <NUM>-<NUM>° (perpendicular), <NUM>-<NUM>°, <NUM>-<NUM>° and <NUM>-<NUM>°.

In an exemplary embodiment of the present method a mold may be used to form the one or more substantially <NUM>-dimensional elements.

In an exemplary embodiment of the present method the substantially <NUM>-dimensional elements may comprise a first cylindrical like element having a first inner radius, at least one substantially flat element, wherein the first cylindrical like element and the at least one substantially flat element are connected at an angle of about <NUM>°.

In an exemplary embodiment of the present method the flat insulation material may be rotated during forming.

In an exemplary embodiment of the present method the insulation material may be a foam.

In an exemplary embodiment of the present method the insulation material may have an inbuilt, water vapor barrier.

In an exemplary embodiment of the present method the insulation material may be a dust and fiber free material.

In an exemplary embodiment of the present method the insulation material may have a closed cell structure, preferably interconnected closed cells.

In an exemplary embodiment of the present method the <NUM>-dimensional structure may comprise at least one element with a radius of > <NUM>, such as > <NUM>.

In an exemplary embodiment the present method may comprise at a first location, in the <NUM>-D structure identifying a plurality of sub-elements, such as from the group of straight sections, bends, couplings, T-junctions, butterfly valves, pipe-couplings, passages through walls and floors, bifurcations, sensors, controllers, closures, vents, locking wheels, supports, suspensions, flanges and branches, for each sub-element individually, identifying the type of sub-element, selecting at least one preformed <NUM>-dimensional element for each identified sub-element to be insulated, and insulating at least one sub-element of the plurality of sub-elements, and optionally preparing and/or ordering the at least one preformed <NUM>-dimensional element for each identified sub-element to be insulated, preferably at a second location.

In an exemplary embodiment of the present method the adhesive is a one- or two-component adhesive, such as an aqueous or solvent-based adhesive, such as comprising one or more of a polychloroprene dispersion, a polyurethane dispersion, a natural rubber dispersion, a styrene-butadiene-styrene copolymer dispersion, a nitrile-butadiene rubber dispersion, a polyvinyl butyral dispersion, a styrene-butadiene rubber dispersion, and combinations thereof, the dispersion comprising <NUM>-<NUM> wt.

In an exemplary embodiment of the present method the flat insulation material comprises at least one recess for receiving a bolt or part thereof at an inner side thereof.

The invention is further detailed by the accompanying example and figures, which are exemplary and explanatory of nature and are not limiting the scope of the invention. To the person skilled in the art it may be clear that many variants, being obvious or not, may be conceivable falling within the scope of protection, defined by the present claims.

<FIG>, <FIG>, <FIG> show steps in the insulation of a complex 3D structure.

<FIG> show examples of complex structures to be insulated.

<FIG> shows an initial step, wherein certain sub-elements are insulated with parts <NUM>. Subsequently in <FIG> an enclosure <NUM> is shown, with schematically drawn particles <NUM>, openings 1a and 1b, of which outlet openings 1b are provided with a mesh <NUM>. In <FIG> particles <NUM> are provided through inlet opening 1a, such as by air-pressure. Therewith the void(s) in enclosure <NUM> are filled with insulation material.

<FIG> shows a view of a fully insulated appendage. <FIG> shows insulation particles used therein.

<FIG> shows a non-insulated, but to be insulated appendage.

<FIG> shows initial preparations, providing some sub-elements for insulation. In the particular case these have recesses for the bolts of the appendage. <FIG> shows some first parts of the appendage being insulated.

Then <FIG> show application of the enclosure around the initially insulated appendage. The enclosure is made of ABS, and transparent. In order to provide a closed environment, apart from the openings in the enclosure, the enclosure is sealed to the appendage, such as by using tape. <FIG> show the partly filled enclosure, with particles, and an enlarged view of the particles used. <FIG> shows a stage in the filling process, wherein particles are provided through a hose, under air pressure. <NUM>-<NUM> show a front view of a full insulation provided thereafter, and <FIG> a rear view. The full insulation may be prepared elsewhere. <FIG> then shows the insulated appendage.

In an example plates of Armaflex are used as insulation material. Preferably the insulation is made of Armaflex®, such as <NUM> or <NUM> thick Armaflex®. In the workshop, that is off-site of a location of application, typically at the home office of the applicant, the Armaflex is cut into the right dimensions, such as by using the exemplary embodiments above. As such the Armaflex are ready to be applied onto the 3D-objects to be isolated at the location thereof, in terms of structure. Then a <NUM> adhesive, such as Armaflex <NUM>, is applied to one side of the insulation material. The prepared insulation material is now left to dry for at least one hour, preferably for at least <NUM> hours, more preferably for at least <NUM> hours, and typically at least <NUM> hours. The adhesive is then dry, and does not provide much adhesive strength anymore; this can be established easily by applying a piece of paper or the like, and removing said piece of paper; this can be done without much force. For protection of the adhesive an removable protection foil may be provided, such as a plastic foil, or paper, but typically there is not much need to do so. This process can be repeated as often is deemed required, such as <NUM>-<NUM> times, such that all preparations for insulation at the location of the 3D-objects are done.

The prepared Armaflex is the transferred to the location of insulation. There the prepared Armaflex is applied to the 3D-object to be insulated. A simple heater, such as a hair dryer, is used to heat the adhesive, to a temperature of <NUM>-<NUM>, during a period of time of typically less than <NUM> sec, such as less than <NUM> sec, before applying the Armaflex. In view of the heating it is preferred to use an insulation material that can withstands temperature of up to <NUM>, preferably up to <NUM>, such as the Armaflex used. In an alternative a HU series inductive heater of RF Heating Consult is used, or likewise an inductive cooking plate of Medion can be used. The inductive heater is steadily moved over the Armaflex, typically with a slow forward and backward movement, as well as over joints and the like. The advantage is amongst others that no vapor is released from the adhesive. In both cases an extremely good adhesion is obtained; the Armaflex can not be removed with human force/human weight anymore. Also the insulation is complete and tight and good joints are obtained, without abrading.

After applying the Armaflex insulation material it is found that the adhesive strength is so high, that it is virtually impossible to remove the applied insulation, at least not by human force/body weight. In addition it is found that by preparing the insulation material at the workshop a much better quality of insulation is achieved, such as more constant, independent of the person applying the insulation material, in a shorter period of (overall) time, and with virtually no gaps/fissures, providing a fluid-tight insulation over the surface of the 3D-object and aesthetic appearance. The present method is especially suited for more complex 3D-objects and/or with a larger diameter, such as couplings.

In an example waste material from the insulation material, considered to be about <NUM>% of the volume used, is processed into small particles of <NUM>-<NUM> size. The small particles are used to fill gaps, remaining after insulation of complex <NUM>-D structures according to the invention.

Claim 1:
Method for applying a thermal insulation on a <NUM>-dimensional structure, the <NUM>-dimensional structure (<NUM>) configured for flowing a fluid therethrough, comprising
providing an enclosure (<NUM>), the enclosure comprising at least one input opening (1a) for providing a flow of insulation material, and at least one output opening (1b) for releasing gas, in particular air, at least one input opening (1a) and at least one output opening (1b) being in fluidic connection with one and another,
providing thermal insulation material, wherein the thermal insulation material comprises individual particles (<NUM>) with a particle size of <NUM>-<NUM>, in particular <NUM>-<NUM>,
providing the particles of insulation material in the enclosure,
substantially filling the enclosure,
characterized in
wrapping the enclosure (<NUM>) around an appendage (<NUM>) of the <NUM>-dimensional structure, and
providing flat thermal insulation material (<NUM>) to the appendage including the enclosure.