GB2220459A - Insulating material - Google Patents

Abstract

An insulating block 2 e.g. of foam adapted to surround the object e.g. a pipe 1 to be insulated comprises a main body of a water repellent insulating material having a profile 4 on its inner and/or outer surface, and a cover 3. The profiles 4 are adapted to space the main body of the insulating material from the object and/or the outer cover 3. The profiles 4 provide for ventilation and drainage between the insulating material, the cover 3 and/or the object surrounded by the insulation and hence reduce corrosion. The profiles 4 may be of block, stud, chevron or ridge form. <IMAGE>

Description

INSULATING MATERIAL This invention relates to insulating material, particularly thermal insulating material.

When heated fluids are passed through pipelines it is generally necessary to conserve the heat in the fluids by surrounding the pipes with insulating material. Suitable insulating materials include mineral fibres and foamed polymers. In order to protect the insulating material from mechanical damage and the weather it is usually encased in an outer cover, e.g. metal cladding. It is, however, difficult to render such covers entirely weatherproof and moisture generally seeps into the insulation and is retained in contact with the pipe. This can lead to corrosion problems.

Temporarily removing the outer cover from the insulation can provide ventilation and drainage but this is a tedious procedure and is not practical in many cases.

We have now discovered an improved form of insulating material which avoids long term contact of moisture with the pipe or other object to be protected.

Thus, according to the present invention there is provided an insulating block adapted to surround the object to be insulated, the block comprising a main body of a water repellant insulating material having a profile on its inner and/or outer surface, and an outer cover, the profile(s) being adapted to space the main body of the insulating material from the object and/or the outer cover.

The geometry of the profiles is not critical provided that some portions of the surface are raised above or some depressed below the general level.

Raised profiles are preferred, however.

Non-limiting examples of suitable profiles include radial or longitudinal ridges, chevrons, blocks and studs.

The surface profile provides means for ventilation and drainage between the insulating material, the cover and/or the object within the insulation.

Drainage holes are preferably provided in the outer cover.

The insulating material may be inherently water repellant, such as a closed cell polymer, or treated to become so.

For open cell or partially open cell insulation (e.g. foamed polymers) and fibrous material which is not inherently water repellant, a semi-permeable membrane or hydrophobic treatment is applied to the surfaces of the insulation before or after surface profiling.

Semipermeable membranes permit the passage of vapour but not liquid water. Thus they keep out most of the water. If any water does penetrate through gaps or imperfections it is vaporised by the heat of the fluid in the pipe or other object to be insulated and passes through the membrane. Corrosion is thereby reduced.

Such membranes may be reinforced with glass fibre cloth and applied to the outer surface of the insulating material to provide weather and mechanical protection.

Covering materials include sheet metals and plastics.

The invention is illustrated with reference to Figures 1-3 of the accompanying drawings wherein Figure 1 is a section of an insulated pipe, Figure 2 is a detail of Figure l, and Figure 3 is a side view of the insulation without the cover.

A pipe 1 is surrounded by a block of hydrophobic mineral fibre insulating material 2 and a steel outer cover 3.

The insulating material is profiled on its outer surface with a regular pattern of raised blocks 4.

The gap 5 between the cover and the main body of the insulation will normally be between 5mm and 20mm.

Claims (12)

Claims:

1. An insulating block adapted to surround the object to be insulated, the block comprising a main body of a water repellant insulating material having a profile on its inner and/or outer surface, and an outer cover, the profile(s) being adapted to space the main body of the insulating material from the object and/or the outer cover.

2. An insulating block according to claim 1 wherein the profile or profiles is or are raised.

3. An insulating block according to claim 2 wherein the profile pattern comprises radial or longitudinal ridges, chevrons, blocks or studs.

4. An insulating block according to any of the preceding claims wherein drainage holes are provided in the outer cover.

5. An insulating block according to any of the preceding claims wherein the insulating material is inherently water repellant.

6. An insulating block according to claim 5 wherein the insulating material is a closed cell polymer.

7. An insulating block according to claim 5 wherein the insulating material is rendered water repellant.

8. an insulating block according to claim 7 whereing the insulating material is an open cell polymer or a fibrous material.

9. An insulating block according to either of claims 7 or 8 wherein the insulating material is rendered water repellant by the application of a semi-permeable membrane to its surface.

10. An insulating material according to either of claims 7 or 8 wherein the insulating material is rendered water repellant by treatment with a hydrophobic material.

11. An insulating block according to any of the previous claims wherein the outer cover is fabricated from sheet metal or plastics.

12. An insulating block as hereinbefore described with reference to Figures 1-3 of the accompanying drawings.