FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(See Section 10)
THERMAL INSULATION SYSTEM / KIT FOR INSULATING HOT PIPES AND THE PROCESS FOR MANUFACTURING THE SAME
PRS Solutions Private Limited, a Company incorporated under the Companies Act, 1956 and having its office at 63, Bombay Samachar Marg, Mumbai - 400 001 Maharashtra State, India.
The following specification particularly describes the nature of this invention and the manner in which it is to be performed


FIELD OF THE INVENTION:
This invention relates to Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same. The said thermal insulation system / kit consisting of two separate components for providing protection and insulation. It is protected against both thermal and radiative conduction of energy. It is easily installed and capable of easily fitting multiple substrate diameters. It is space-saving, lightweight, and durable. The thermal insulation system / kit comprises an inner layer of insulating mat laminated from one side with an aluminized glass fabric and an outer layer of reflective aluminized glass fabric tape. The said kit could be used for numerous purposes. One of the applications for this kit, but not limited to, is for minimising the loss of heat from the working fluid to the surrounding environment to save energy and cost by thermal insulation of pipe lines carrying fluids where the liquid is required to be maintained at a optimum temperature.
DESCRIPTION OF THE PRIOR-ART :
Thermal insulation is the most preferred method of preventing heat energy from escaping a hot object to another surface or surrounding which is at a lower temperature. In other words, a suitable thermal insulation system is used to keep the contents in an enclosed area such as a pipe line at a optimum temperature. Such thermal insulation systems help in preventing heat transfer from the contents of the pipe line to atmosphere and vice versa. Heat is transferred from one material to another by conduction, convection and/or radiation. Insulators are used to minimize that transfer of heat where two objects in a vicinity are at different temperatures.
The term thermal insulation can refer to materials used to reduce the rate of heat transfer, or the methods and processes used to reduce heat transfer. The major types of insulation are associated with the major types of heat transfer. While reflectors are used to reduce radiative heat transfer, foams, fibrous materials or air spaces are used to reduce conductive and convective heat transfer by reducing physical contact


between objects and by reducing movement of gases around the insulated object respectively. Combinations of some of these methods are often used to increase the effeciency of thermal insulation.
Many different materials can be used as insulators. Many organic insulators are made from petrochemicals and recycled plastic. Many inorganic insulators are made from recycled materials such as glass (e.g. glass wool). Most insulators in common use rely on the principle of trapping air to reduce convective heat transfer. These insulators can be fibrous (e.g. asbestous), cellular (e.g. cork or plastic foam), or granular (e.g. sintered refractory materials). Standard types of insulation, such as fiberglass, asbestos, plastic foam, and cellulose primarily reduce heat transfer by trapping air or some type of a gas. Thus, these products or technologies reduce convection as a primary method of reducing heat transfer.
For practical and economic reasons, it is undesirable to use too much insulation. Specifications of industrial insulation are usually done following a heat-transfer analysis. It is often sufficient to choose the thickness of the insulative layer intuitively, based on rules of thumb that account for cost and desired results.
Conventionally, glass wool is used as an insulating material to prevent this heat loss. However, glass wool primarily reduce heat transfer by trapping air or some type of a gas thus reducing convection as a primary method of reducing heat transfer. Further use of glass wool is further complicated due to its large volume requirement to achieve effective control over heat loss and its adverse effect on health such as its irritating effect on skin, eyes and throat.
SUMMARY OF INVENTION
In the present invention an attempt has been made to prepare a thermal insulation system / kit which is suitable for insulating hot pipes. The said thermal insulation


system / kit when applied on pipe lines, as per recommended installation procedure described herein, facilitates retention of optimum temperature of the contents inside the pipes by substantially reducing heat loss to the surrounding atmosphere by all three modes of heat transfer viz. Conduction, Convection and Radiation. The thermal insulation system / kit of the present invention comprises of two separate components (hereinafter called as Tape A and Tape B) for easy application on pipes of any diameter and length.
'Tape A' (figure 1) of the present invention is a laminate of insulation mat of thickness 1 to 10 mm, preferably of 2 to 4 mm (insulation mat of thickness lower than 1mm & higher than 10 mm can also be used) and aluminized glass fabric on at least on one side of the said insulation mat. The manufacturing of the 'Tape A' for this thermal insulation system comprises of (a) coating of pressure sensitive silicone adhesive with a deposition of 10 to 25 g/m2 on glossy side of soft Aluminium foil. However, the adhesive deposition is not critical for the performance of the thermal insulation system of this invention and any other deposition can be used. The coating is carried out by use of conventional methods followed by drying operation which is also carried out by known conventional methods. The adhesive coated side of the Aluminium foil is then laminated to woven glass fabric by passing through two laminating rollers under pressure thereby obtaining an aluminized glass fabric (b) coating of pressure sensitive silicone adhesive with a deposition of preferably 10 to 25 g/m2 on the woven glass fabric side of the laminate obtained by step (a) above. However, the adhesive deposition is not critical for the performance of the thermal insulation system of this invention and any other deposition can be used. This coating also is carried out by use of conventional methods followed by drying operation which is also carried out by known conventional methods (c) lamination of insulation mat to the adhesive coated side of the pressure sensitive adhesive coated product obtained by step (b) by passing the two through laminating rollers under pressure thereby obtaining tape 'Tape A' and (d) slitting of the composite thus obtained in step (c) to desired width and length using conventional methods of slitting.


Tape B' (figure 2) of the present invention is a super soft Aluminium foil- woven glass fabric pressure sensitive adhesive tape having silicone adhesive on the glass fabric side. The silicone adhesive side of the tape is protected by laminating a PVC or HDPE liner having raised pattern on one side.
The manufacturing of the 'Tape B' for this thermal insulation system comprises of (a) coating of pressure sensitive silicone adhesive with a deposition of 10 to 25 g/m2 on glossy side of soft Aluminium foil. However, the adhesive deposition is not critical for the performance of the thermal insulation system of this invention and any other deposition can be used. The coating is carried out by use of conventional methods followed by drying operation which is also carried out by known conventional methods. The adhesive coated side of the Aluminium foil is then laminated to woven glass fabric by passing the two under laminating rollers under pressure thereby obtaining an aluminized glass fabric (b) coating of pressure sensitive silicone adhesive with a deposition of 10 to 25 g/m2 on the woven glass fabric side of the laminate obtained by step (a) above. However, the adhesive deposition is not critical for the performance of the thermal insulation system of this invention and any other deposition can be used. This coating is carried out by use of conventional methods followed by drying operation which is also carried out by known conventional methods (c) lamination of PVC or HDPE film liner having raised pattern on one side in such a fashion so that the raised pattern side is in contact with the pressure sensitive adhesive coated side of the product obtained by step (b) by pressing the two under laminating rollers with a minimum pressure thereby obtaining tape 'Tape B' and (d) slitting of the composite thus obtained in step (c) to desired width and length using conventional methods of slitting.
The thermal insulation system / kit for insulating hot pipes thus obtained has the
following features:
[1] Available in kit form and is user friendly.
[2] Useful for insulating hot pipes up to a temperature of 180°C.
[3] It is highly flexible, easy to apply, light weight, less thick and conformable hence
can be applied on highly contoured surfaces.


[4] It is flame retardant and passes UL -94 test at V-l level.
[5] Helps in reducing fire hazard due to oil spillage on hot surfaces.
[6] It is weather resistant and does not get deteriorated due to outdoor weathering.
[7] Special fiber mat provides insulation against conduction.
[8] Aluminium foil is having very low emittance values (typically 0.03 compared to
0.90 for most insulation) which significantly reduces radiative heat loss from surface.
[9] The change in thermal performance due to compaction or moisture absorption, a
common concern with mass insulation, is not an issue with this invention as
Aluminium foil used is moisture resistant and is waterproof.
[10] It is free of any harmful substance like Asbestos and does not irritate the skin,
eyes or throat and contain no substances which will out-gas.
[11] It is free from any leachable chlorides hence does not cause any corrosion on
metal.
For maximum efficiency of the invented thermal insulation system the recommended installation procedure involves:
(a) Application of one layer of 'Tape A' on the outer surface of the pipe to be insulated with the insulation mat side of the tape touching the metal surface in a spiral winding fashion with proper overlapping between two subsequent layers of the tape in order to ensure no gap (b) sealing the ends of 'Tape A' with 'Tape B' to prevent the tight winding to open out followed by (c) removal of PVC /HDPE layer from 'Tape B' and application of tightly wound layer of 'Tape B' over 'Tape A' in spiral winding fashion with 50% overlap between two consecutive layers ensuring complete coverage of Tape A'.
When thermal insulation system for hot pipes is applied on the outer surface of the hot pipes carrying fluids at high temperature as per the procedure described above it provides following benefits:


[1] Reduces the possibility of human contact with heated ducts and pipes thereby
reducing the risk of injury.
[2] Reduction in ambient temperature around the hot pipes resulting in better working
condition.
[3] Avoids heating of adjacent materials which can occur when the heat released
conflicts with the fluid temperature in adjacent pipes and ducts, or affects the
temperature of local materials such as cables, plastics, paper or board products, etc.
[4] Fire risk is minimized as the material used for insulation is flame retardant.
[5] Minimises the loss of heat from the working fluid to the surrounding environment
which helps save energy and cost.
[6] Maintenance friendly.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
Figure 1 (Tape A)

llllll/lllllllllllllllllllllllllllllllllllllllllllllll Aluminium foil
lllllllllllllllllllllllll/llllllllllllllllllllllllllll Silicone pressure sensitive adhesive
llllll/llllllllllllllllll/lllllllllllllllllllllllllll Woven glass fabric
lllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
lllllllllllllllllllllllll/llllllllllllllllll/lllllll Insulation mat
Figure 2 (Tape B)

llllllllllllllllllllllllllllllllllllllllllllllllllllllll Aluminium foil
llllllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
llllllllllllllllllllllllllllllllllllllllllllllllllllll Woven glass fabric
lllllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
lllllllllllllllllllllllllllllllllllllllllllllllllllllll Embossed PVC film liner

Figure 3 (assembly of tape A and Tape B to obtain thermal insulation system)

lllllllllllllllllllllllllllllllllllllllllllllllllllllll Aluminium foil
lllllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
llllllllllllllllllllllllllllllllllllllllllllllllllllll Woven glass fabric
lllllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
llllllllllllllllllllllllllllllllllllllllllllllllllllll Aluminium foil
llllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
lllllllllllllllllllllllllllllllllllllllllllllllllllll Woven glass fabric
lllllllllllllllllllllllllllllllllllllllllllllllllllll Silicone pressure sensitive adhesive
llllllllllllllllllllllllllllllllllllllllllllllllllll Insulation mat
llllllllllllllllllllllllllllllllllllllllllllllllllll Outer surface of pipe to be insulated

WE CLAIM :
1. Thermal insulation system / kit for insulating hot pipes comprises of two components and the process for manufacturing the same comprises of the following steps:-
[1.1] Manufacture of 'Tape A':
1.1(a) coating glossy side of soft Aluminium foil with a pressure sensitive silicone adhesive to achieve the required dry adhesive weight by use of conventional coating methods followed by drying with conventional methods and laminating coated side of the soft Aluminium foil with woven glass fabric under pressure to obtain aluminized glass fabric;
1.1(b) coating glass fabric side of the aluminized glass cloth so obtained in step (a) with a pressure sensitive silicone adhesive to achieve the required dry adhesive weight by use of conventional coating methods followed by drying with conventional methods followed by lamination of insulation mat to the adhesive coated side 1.1(c) the laminate so obtained is slit to desired width and length by conventional slitting machines;
[1.2] Manufacture of Tape B':
1.2(a) coating glossy side of soft Aluminium foil with a pressure sensitive silicone adhesive to achieve the required dry adhesive weight by use of conventional coating methods followed by drying with conventional methods and laminating coated side of the soft Aluminium foil with woven glass fabric under pressure to obtain aluminized glass fabric;
1.2(b) coating glass fabric side of the laminate obtained in step (a) with a pressure sensitive silicone adhesive to achieve the required dry adhesive weight by use of conventional coating methods followed by drying with conventional methods followed by lamination of embossed side of PVC or HDPE film liner to the adhesive coated side


1.2(c) the laminate so obtained is slit to desired width and length by conventional slitting machines;
[1.3] Installation of thermal insulation system:
Installation of thermal insulation system by combining 'Tape A' and
'Tape B' as per the recommended installation procedure involving
following steps:
1.3(a) application of one layer of 'Tape A' on the outer surface of the
pipe to be insulated with the insulation mat side of the tape touching
the metal surface in a spiral winding fashion with proper overlapping
between two subsequent layers of the tape in order to ensure no gap
1.3(b) sealing the ends of Tape A' with 'Tape B' to prevent the tight
winding to open out followed by
1.3(c) removal of PVC /HDPE layer from 'Tape B' and application of
tightly wound layer of 'Tape B' over 'Tape A' in spiral winding
fashion with 50% overlap between two consecutive layers ensuring
complete coverage of 'Tape A’.
2. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein Aluminium foils used is soft foil having thickness ranging from 10 to 50 micron.
3. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein pressure sensitive silicone adhesive is the one available in the market and is further formulated to cure by using organic peroxide catalysts such as Benzoyl Peroxide, 2-4 dichloro benzoyl peroxide etc.
4. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein adhesive coating on aluminium foil is done to give a adhesive deposition of preferably 10 to 25


g/m2 by conventional coating techniques and is also dried by using conventional drying equipment. However, the adhesive deposition is not critical for the performance of the thermal insulation system of this invention and any other deposition can be used.
5. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein the Glass Fabric used is a woven glass fabric preferably having a thickness of more than 0.025mm, however, any suitable thickness can also be used.
6. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein the insulation mat used can be Glassmat, Silicamat, Meta Aramide mat, or Ceramic mat preferably having a thickness varying between 1 to 10 mm (insulation mat of thickness lower than 1 mm and higher than 10 mm can also be used).
7. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein the insulation mat is laminated to the adhesive coated side of aluminized glass fabric as claimed in Claim 1.1 (a) by use of pressure to obtain 'Tape A' in a conventional coating cum laminating machines.
8. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein aluminized glass fabric as claimed in Claim 1.2(a) is laminated with embossed side of PVC or HDPE film liner to obtain 'Tape B' by use of conventional coating cum laminating machines.
9. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 wherein maximum efficiency


of thermal insulation can be obtained when installation is carried out as claimed in Claim 1.3 above.
10. Thermal insulation system / kit for insulating hot pipes and the process for manufacturing the same as claimed in Claim 1 to 9 by which Thermal insulation system / kit for insulating hot pipes is obtained.




ABSTRACT
A thermal insulation system / kit includes two separate components for providing protection against both convection and radiative conduction of heat energy. It is easily installed, re-usable, space-saving , lightweight, waterproof, flame retardant, flexible and capable of easily fitting multiple substrate diameters. The system / kit comprises an inner insulation layer of insulation mat laminated on one side with a layer of reflective aluminized glass fabric with reflective side remaining outside. The outer insulation layer is a layer of reflective material which is aluminized glass fabric obtained by lamination of woven glass fabric on to the soft Aluminium foil using pressure sensitive silicone adhesive. The thermal insulation system / kit provides much desired property of heat retention of fluids inside pipes and one of the application for this system / kit, but not limited to, is for minimising the loss of heat from the working fluid to the surrounding environment to save energy and cost by thermal insulation of hot pipe up to a temperature of 180°C carrying fluids where the liquid is required to be maintained at a optimum temperature.