WO2003087676A1

WO2003087676A1 - Gas handling system

Info

Publication number: WO2003087676A1
Application number: PCT/SE2003/000579
Authority: WO
Inventors: Daniel Westberg; Gunnar Roos; Tobias SAGSTRÖM; Lisa Flawn Orpana; William Lawrance; Peder Evers
Original assignee: Fläkt Woods AB
Priority date: 2002-04-09
Filing date: 2003-04-09
Publication date: 2003-10-23
Also published as: DK1497593T3; AU2003224528A1; EP1497593B1; SE525055C2; DE60307080T2; EP1497593A1; ATE334356T1; DE60307080D1; SE0201061D0; SE0201061L

Abstract

A gas handling system, comprising at least one component such as a fan, filter, sound attenuator, humidifier, heater, cooler or heat exchanger enclosed in a casing that is constructed from at least one unit (10) whose constituent elements are glued together.

Description

Gas handling system

TECHNICAL FIELD

The present invention relates to a gas handling system, such an air- handling unit, comprising at least one component such as a fan, filter, sound attenuator, humidifier, heater, cooler or heat exchanger. More particularly the present invention concerns the casing around said at least one component of the gas handling system and a method of constructing said casing.

BACKGROUND OF THE INVENTION

Gas handling systems are often custom-built and delivered to customers as a single factory-assembled block or in a multitude of elements that have to be constructed on site. Currently gas-handling systems are constructed using a framework of galvanized or stainless steel parts that are joined together. Steel panels are attached to the framework to form the outer casing of the system and the components of the gas handling system are mounted onto the casing.

The construction of the outer casing is a complicated and time-consuming process as the metal panels have to be cut to shape and attached to the framework of the casing by riveting, screwing or welding. Manufacturing tolerances are high, as the elements constituting the system have to be produced with great precision to ensure accurate joining of the various parts. The casing comprises many individual parts, which results in high material costs. The system must be constructed with care and skill and mounting tools such as screwdrivers, riveting or welding tools are often required which also make the assembly costly. Conventional systems are quite heavy and are thus inconvenient to transport and handle. In the event of failure of a component of the gas handling system or if maintenance work or cleaning needs to be carried out, access to, and/or removal of the components that are fastened to the casing is troublesome due to the necessary screwing and unscrewing.

The demands on gas quality in different environments vary depending on the activities pursued in the different environments. Places such as hospitals, laboratories and clean rooms utilized in the food, pharmaceutical and electronics manufacturing industry place extremely stringent demands on ventilation and air conditioning systems as people and/or products must be protected against pollutants, bacteria and toxic substances. The gas flowing through such systems can be at a high or low temperature and is sometimes corrosive and laden with dust. If there is a temperature difference between the outside the system and the gas inside the system, condensation can occur either on the inside or the outside of the casing.

As the number of clean and hygienic applications continues to increase there is a growing need for safe and easy-to-use gas handling units that are easy to install and clean and which preferably contain no recesses or projections in which unwanted matter such as dirt or moisture can collect.

SUMMARY OF THE INVENTION

It is an object of this invention to provide a simplified, lightweight gas handling system that can be manufactured easily and that ensures simple and rapid assembly and thus low cost installation.

This and other objects of the invention are achieved by utilizing a gas handling system, comprising at least one component such as a fan, filter, sound attenuator, humidifier, heater, cooler or heat exchanger enclosed in a casing that comprises at least one unit whose constituent elements are glued together or a plurality of conjoined units that comprise sealing means to provide a gas-tight seal between adjacent units.

According to a preferred embodiment of the invention the gas handling system is constructed by prefabricating a plurality of individual units by gluing their constituent elements together, aligning the units and joining said units together for example by applying a force to the ends of casing to push the individual units together.

According to another preferred embodiment of the invention each unit comprises at least one channel that can be aligned with corresponding channels in other units when a plurality of units are joined together. Such a channel can be used as a guide for a tension element that is used to draw a plurality of units together. For example each unit is placed on a common beam or base plate and then a person can draw the units together without requiring any special tools. The assembly work does not have to be carried out by a skilled person and because the casing is constructed first and then at least one component such as a fan, filter, sound attenuator, humidifier, heater, cooler or heat exchanger is inserted into said casing, great strength is not required. An advantage of this type of assembly is that the person constructing the system does not need to have access to all sides of the units. He/she merely aligns the units and draws them together. This means that a system can, for example, be constructed adjacent to a wall or in a space-restricted location.

In another preferred embodiment of the invention said channels contain connecting means between the components inside the casing i.e. electrical cables or optical fibres for transmitting signals between the components. In this way the connecting means do not hinder the flow of gas passing through the system as they are separated from the gas stream. In a preferred embodiment of the invention sealing means are applied between adjacent units to provide a gas-tight seal. The sealing means can be adapted to seal off the channels from the gas passing through the gas- handling system. Another possibility is to provide a light source, such as light emitting diodes, in a transparent channel along the inside of the casing so as to illuminate the inside of the system during maintenance or repair work or to aid monitoring of the system by sensors such as surveillance cameras when the system is in use. The presence of surveillance cameras along the inside of the casing eliminates the need for inspection windows, which are common in conventional systems, which decreases the number of potential leak sites.

According to another preferred embodiment of the invention the units, which can have any cross-sectional shape, have the same transverse dimensions so that they are interchangeable. The individual units can be separated easily so the gas-handling system can be readily adapted to a different length or function to meet different/changing requirements. Furthermore if a supplier provides a standard range of cross-sectional sizes, systems can be modified easily by ordering new supplementary or replacement units. This dimensioning also aids efficient packaging, storage, handling, transportation and installation of the system.

According to another preferred embodiment of the invention the constituent elements of a unit comprise spacer means that position the elements at the optimum distance for gluing. The spacer means can either be incorporated into the design of the constituent elements or can be placed in-between elements that are to be glued together during the assembly of the unit. The glue used can be adapted to have vibration-damping properties.

The casing according to the present invention can be made of any material however according to a preferred embodiment of the invention the casing comprises a material having a density up to 3000kgm^"3, preferably in the range 100 to 500 kgm^"3 thereby significantly reducing the weight of the gas handling system as compared to a conventional system. The material is chosen to provide an inner casing surface that is at least one of the following: smooth, impenetrable, hygroscopic, non-hygroscopic, diffusion- and emission-free, wear resistant, thermally stable and/or chemical resistant.

According to preferred embodiments of the invention the casing material comprises either a homogeneous material, such as a polymer/plastic, a composite, or a laminate fused by direct lamination under pressure and at high temperature such as Artboard™ or a laminate fused by high-pressure lamination such as Perstorp Laminate™. Both of these laminates are currently used as flooring. According to a preferred embodiment of the invention the casing comprises material that is self-supporting and which does not require a supporting framework as a foundation.

Artboard™ is a fiber composite laminate consisting of mainly thermoset plastic and glass fibre having a density of 160 kgm^"3. Using Artboard as the casing material can therefore reduce the weight of a gas handling system by up to 70%. Perstorp Laminate™ is a thermoset composite plastic fused at high temperature and pressure to form cross-linked polymers providing a stable, homogeneous material. It consists of layers of kraft paper, a brown paper made from high-quality sulphate wood pulp impregnated with phenolic resin which form a strong, rigid core and paper impregnated with clear melamine resin which provides an immensely durable, smooth surface. It has a density of 1400 kgm^"3, it is unaffected by most chemicals, it is non-porous to water, it is stable at temperatures up to 180°C and it will not nourish or support fungi, moulds or bacteria which makes it suitable for hygienic applications. These laminates provide a leak-free casing and by modifying their thickness and resin formulation, their performance can be tailored to suit specific applications. The laminates have high-dimensional stability and high mechanical strength yet are resilient and thus energy absorbent. By varying the density, the shock absorbing and sound attenuating characteristics can be adjusted to meet specific requirements.

According to a preferred embodiment of the invention the internal corners of the casing are rounded to produce perfectly smooth internal walls making cleaning easier and reducing the number of sites at which unwanted matter such as dirt or moisture can collect. This can be done by inserting corner joint pieces for example. In another preferred embodiment the casing incorporates at least one drainage canal to facilitate cleaning of the system. A gas handling system according to the present invention is therefore suitable for hygienic applications such as in a hospital, laboratory, in offshore or electronics applications or any other environment requiring a strictly controlled gas atmosphere.

According to another preferred embodiment of the invention the said at least one component making up the gas handling system is supported on a structure that is inserted into or removed from the system via openings in the casing. This supporting structure can be a rack for example to which said component, or a plurality of components, is/are fastened. The components can thus held in place without having to be fastened to the casing. In a preferred embodiment of the invention the surface of the supporting structure that makes contact with the casing comprises a low friction material that aids its movement into and out of said casing. In another preferred embodiment of the invention the supporting structure moves along guide rails or low friction material fixed to the inside of said casing. Such an arrangement means that components can be easily and rapidly installed and subsequently removed from the system for maintenance, replacement or cleaning. In another preferred embodiment of the invention the supporting structure comprises a panel of material that forms part of the casing when the supporting structure is in position inside the casing.

BRIEF DESCRIPTION OF THE DRAWING

The invention will now be described by way of example and with reference to the accompanying drawing in which:

figure 1 depicts the constituent elements of a single unit according to a preferred embodiment of the invention, figure 2 shows a constituent part of a unit according to a preferred embodiment of the invention,

figure 3 illustrates a method of conjoining a plurality of units according to a preferred embodiment of the invention,

figure 4 shows part of the casing of a gas-handling system according to a preferred embodiment of the invention, and

figure 5 illustrates a casing material according to a preferred embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Figure 1 depicts the constituent elements of a single unit 10 having a square cross-section. The unit can of course be of any cross-sectional shape and size so that it can accommodate either a single component or an entire gas handling system. Since the number of elements constituting a single unit can be reduced as by elimination of screws, the unit and thus the entire casing can be assembled at low cost. The unit comprises small channels 11 that run along the length of the unit. These channels can be aligned with corresponding channels in other units and can be used as a guide for a tension element when conjoining a plurality of units, or for electric/optic cables or a light source for example. The channels 11 can be located at the top, bottom and/or sides of the unit(s). Channels that carry light to illuminate the inside of the casing must run internally along the inside of the units however the channels used as guides for a tension element or to accommodate connection cables may also be located externally along the outside of the units.

Figure 2 shows part of the element 12 indicated in figure 1, which contains a channel 11 through which a tension element/electric or optic cable can be threaded. The element comprises spacer means 13 to position adjacent elements at the optimum distance for gluing together.

Figure 3 illustrates a method of conjoining three prefabricated units 10. The units are placed on a common beam, movable supporting means or on a low friction surface and tension elements 14, that are threaded through channels 11 running along the length of the units are used to draw the individual units together. The method of constructing a casing therefore comprises the steps of prefabricating individual units each having at least one channel that can be aligned with corresponding channels in other units, aligning the units, threading a tension element through said channels and drawing said units together. The units comprise sealing means 15 to provide a gas-tight seal between adjacent units. The sealing means 15 are arranged to seal off the channels 11 from the gas stream.

Figure 4 shows two conjoined units 10. One of the units contains a component (not shown) of a gas handling system that is supported on structure 16 that can be inserted into and removed from the system. The units comprise removable panels or doors that are sealed to the smooth outer surface of the casing once the components of the gas handling system have been placed inside the casing. In another preferred embodiment of the invention the supporting structure 16 that bears the component is constructed to include a panel that provides part of the casing when it is in place inside the system.

Figure 5 shows a preferred casing material for a gas handling system. It comprises a laminate 18 having a core 19 consisting of layers of brown paper made from high-quality sulphate wood pulp impregnated with phenolic resin. The surfaces 20 of the laminate comprise paper impregnated with clear melamine resin. The laminate can be modified to contain energy absorbing material.

While only certain preferred features of the present invention have been illustrated and described, many modifications and changes will be apparent to those skilled in the art. It is therefore to be understood that all such modifications and changes of the present invention fall within the scope of the claims.

Claims

1. A gas handling system, comprising at least one component such as a fan, filter, sound attenuator, humidifier, heater, cooler or heat exchanger

5 enclosed in a casing, characterized in that said casing includes at least one unit (10) whose constituent elements are glued together.

2. A gas handling system according to claim 1 , characterized in that said casing comprises a plurality of conjoined units (10) that comprise o sealing means (15) to provide a gas-tight seal between adjacent units.

3. A system according to claim 2, characterized in that each unit (10) comprises at least one channel (11) that aligns with corresponding channels in other units when said units are joined together to form said s casing.

4. A system according to claim 3, characterized in that said at least one channel (11) is used as a guide for a tension element (14) that draws the units (10) together. 0

5. A system according to claims 3 or 4, characterized in that said at least one channel (11) contains electrical/optical cables or a light source, that illuminates the inside of the casing.

5 6. A system according to any of claims 2-5, characterized in that the units (10) have the same transverse dimensions so that they are interchangeable.

7. A system according to any preceding claims, characterized in that said o constituent elements comprise spacer means (13) that position said elements at the optimum distance for gluing to other elements.

8. A system according to any preceding claims, characterized in that said casing comprises a material having a density up to 2500 kgm^"3, preferably in the range 100 to 500 kgm^"3

9. A system according to claim 8, characterized in that said material provides an inner casing surface that is at least one of the following: smooth, impenetrable, hygroscopic, non-hygroscopic, diffusion- and emission-free, wear resistant, thermally stable, chemical resistant.

10. A system according to claims 8 or 9, characterized in that said material comprises a homogeneous or composite material.

11. A system according to claims 8 or 9, characterized in that said material comprises a laminate or a high-pressure laminate (18).

12. A system according to any of claims 8-11 , characterized in that said material comprises an energy absorbing material.

13. A system according to any preceding claims, characterized in that the internal corners of the casing are rounded to produce perfectly smooth internal walls.

14. A system according to any preceding claims, characterized in that the casing incorporates at least one drainage canal to facilitate cleaning of the system.

15. A system according to any preceding claims, characterized in that said at least one component is supported on a structure (16) that is inserted into or removed from said casing.

16. A system according to claim 15, characterized in that the surface of the supporting structure (16) that makes contact with the casing comprises a low friction material that aids its movement into and out of said casing.

17. A system according to claims 15 or 16, characterized in that said supporting structure (16) moves along guide rails or low friction material fixed to the inside of said casing.

18. A system according to any of claims 15-17, characterized in that said supporting structure (16) comprises a panel that forms part of the casing when the supporting structure is in position inside the casing.

19. A system according to any preceding claims, characterized in that it further comprises sensors, such as surveillance cameras, along the inside of the casing to monitor the system.

20. A method of constructing a gas handling system characterized in that it comprises the steps of prefabricating a plurality of individual units (10) by gluing their constituent elements together, aligning the units and joining said units together.

21. A method according to claim 20, characterized in that said units (10) each have at least one channel (11) that can be aligned with corresponding channels in other units, aligning the units, threading a tension element (14) through said channels and drawing said units together.

22. A method according to claims 20 or 21 , characterized in that it further comprises the step of applying sealing means (15) to provide a gas- tight- seal between adjacent units (10).

23. A method according to any of claims 20-22, characterized in that it further comprises the step of inserting at least one component such as a fan, filter, sound attenuator, humidifier, heater, cooler or heat exchanger into said casing.

24. Use of a system according to any of claims 1-19 in a hospital, laboratory, in offshore or electronics applications or any other environment requiring a strictly controlled gas atmosphere.