US 2180373 A
Description (OCR text may contain errors)
Nov. 21, 1939. l.. T. slBLEY Er A1. l2,180,373
HEAT INSULATING PANEL Filed Oct. 29, 1937 INVENToRs. fm 7.' .Sibley avay J. .Smil
56am ATTORNEY Patented Nov. 21, 1939 i UNITED STATES PATENT ,OFFICE HEAT INSULATING PANEL Leon T. Sibley, Rutherford, N. L, and Roy J.
poration of Delaware Application October 29,
'This invention relates to heat insulating devices and more particularly to a pre-fabricated paneltype of metal assembly that may be used on various industrial equipment such as for example oil tanks to preserve heat. The panel is characterized by having a metal basket connected to a sheet metal cover and spaced therefrom by metal connectors.
Heretofore, the conventional methods of heat insulating various industrial equipment such as storage tanks, fractionating columns, and vacuum towers was to rigidly fasten to the equipment layers of insulating material such as magnesia or cement or layers of rock wool. Thse insulating layers were fastened to the device to be insulated by means of chicken wire, metal laths, galvanized wires, etc. In some instances particularly where high temperatures are involved, several of these insulation layers with metallic supports have been commonly used on the industrial equipment. After these insulating layers are applied, which in itself is time consuming and expensive, the entire outer surface'is then plastered with a layer of asbestos or rock wool cement to which is added a mixture of Portland cement or-other plastic materials to produce a hardened surface. This cementing operation is necessary to seal the cracks, joints and broken segments of the previously applied insulation layers.
In view of the fact that the above described heat insulating materials as used are exposed to general weather conditions which would normally cause deterioration, it has heretofore been necessary to Waterproof the entire exposed area. A number of different weather-proofing methods have been tried but have been found to possess certain practical disadvantages. One of the best of these attempts consists in the application of a plastic water-proofing cement trowelled or otherwise spread over the hard-finish cement to a thickness of approximately one-quarter of an inch. This method gives satisfactory results initially, but over a period of time under weathering conditions the plastic cement coating deteriorates and loses its water-proofing effectiveness. AIt is also subject to rupture by leaks of hot air from the insulated equipment and by contraction and expansion of the insulated material wit changes in temperature.
An object of the present invention is to' provide a self-supporting weather resistant heat insulating device having high heat preserving eiciency.
In accordance with the present invention the above described disadvantages and limitations characteristic of the insulating devices used here- Scott, Forest Hills, Long Island, N. Y., assignors to Alfol Insulation Company, Inc., a cor- 1937, Serial No.- 171,681
(Cl. 18S-34) tofore have been overcome by the use of a simple but eilicient metal panel-type of heat insulator. 'I'his heat insulating device may be prefabricated and may be made in units of any desired size and shape whereby installation of these units around ti or upon the equipment to be insulated can be easily effected. 'I'he device of this invention comprises generally, an expanded metal or mesh-like basket having a complete inner lining made of relatively thin metal foil, or foil coated paper, or 1U other heat insulating material and having a series of strips or layers of crumpled thin metal foil spaced apart and arranged within the metal foil inner lining, or a mass, or strips of any other suitable heat insulating material such as rock wool, 15 cotton etc., loosely or compactly arranged, and a sheet metal cover attached to and covering the top of the metal basket; the attachment being made by separate metal connectors that space the basket away from the sheet metal cover. The 20 strips or layers of metal foil or other heat insulating material arranged in the basket may be spaced apart to provide desired air spaces between strips for preventing transfer of heat across or through the basket.
This new type of heat insulating unit is easily applied to flat or round surfaces such as, for example, square or round tanks, columns, pipes, etc. Without any positive physical attachment of the unit to the equipment which it insulates, the metal 30 baskets with outer sheet metal covers being placed around and in close contact with the structure to be insulated. When used on rounded surfaces the ,metal panels are given a suitable curvature. Upon installation, the baskets are joined together by 35 meansof connecting cli-ps and bolts mounted on 'the outer surface of the sheet metal cover so as to provide a self-supporting unitary cover for the insulated structure. The metal basket or panel of this invention is light in weight, is character- 40 ized by high heat insulation elciency, is fire proof, vermin-proof, and water-proof and may be easily assembled.
The novel features o'f this invention are setv forth'with particularity in the appended claims. 45 The invention itself, however, both as to organization and method of operation may be easily understood from the following description taken in conjunction with the accompanying drawing in which:
Fig. 1 is a top plan view of the heat insulating metal basket panel; A f
Fig. 2 is a side view of the panel partly broken away to show'the metal foil inner lining and spaced strips of metal' foil;
Fig. 3 is an end view of a curved form of the metal basket panel;
Fig. 4 is a bottom perspective view of a curved form of the metal basket panel Fig. 5 is a plan View of one of the metal foil strips used in the basket, only part of the strip being crumpled to show the irregular formation; and
Fig. 6 is a front view illustrating the method of application of the metal basket panels to a surface to be insulated. y
Fig. 'l is a modification of Fig. 4.
Fig. 8 isa detail of the clincher strip and its mode of application.
Referring now more in detail to the several figures of the drawing, it will be seen that the metal panel comprises an expanded metal or meshlike basket I0, the top of which is covered by a'sheet metal jacket II, the latter being attached to the metal basket by means of a number of metal clips I2. These clips are welded at different points 4around the periphery of the top edge of the expanded metal basket. The clipsl are angular in form and the metal basket rests upon one extended leg of the angle and is welded to one or two of the wires in the side wall of the basket. This type of small surface contact connection between the metal basket and sheet metal jacket avoids any appreciable through-metal contact between these two members. In place of the clips I2 bent metal rods 21, shown in Fig. '7, may be used. These rods are welded to thesheet metal cover II at the points 28 and may 'also be welded to the metal basket I if necessary. The outer sheet metal jacket II may be reinforced whenever necessary by means of angle-irons such as shown at I3 welded to the inside of the jacket.
The long side edges of the sheet metal jacket ll are folded back a suitable distance for example, one half of an inch to form a clincher edge shown at I4. This clincher edge extends along each side of the panel jackets. On the outside face of the metal jacket II are welded a suitable number of angular metal clips I5. rThese clips are drilled to form holes I6 which accommodate a carriage bolt Il as shown in Fig. 6. When the panels are erected these carriage bolts `are placed in the clips of adjacent panels to temporarily hold the panels in approximately correct position, as explained more in detail hereinafter. These clips I and bolts Il are not always necessary and may be omitted if desired.
The bottom edge of each panel is constructed so that it has an overhanging jacket I8 extending a suitable distance, for example three inches, beyond the edge of the basket I0. 'I'he top edge of the jacket II is approximately flush with the end of the basket I0. On the outside surface of the jacket II near -each of its ends are Welded several Z-shaped clincher clips I9. These clips may be approximately of an inch wide and may be made of 13-gauge metal. They may be located conveniently about 3 inches from the end of the metal jacket II. The clips I9 may be replaced by sheet metal screws if desired.
Located within the metal basket I0, as shown in Fig. 2 is a heat reflective inner lining 20. This inner lining may be made of thin metal foil such as aluminum foil or it may consist of v`foil coated paper or any other suitable heat reflective material. The lining is applied flat against the bottom and sides of the metal basket. I0 and with its reflective surfaces exposed through the meshes of the basket on all ve suu'faces. This lining may, if desired, cover the open top of the basket just beneath the outer sheet metal jacket I I. Located Within the inner lining are a plurality of thin strips of heat reflective material 22. These strips may be made of aluminum or other metal foil sufficiently thin to have negligible heat conducting capacity and having a bright reflective surface to efliciently reflect heat. transmitted thereto. These metal foil or other suitable thin strips of heat insulating material extend the length of the metal basket and are fastened at each end by any suitable means. .For example they may be cemented to the inner lining of the metal basket on each end by means of sodium silicate or other adhesive. These heat reflective strips are spaced apart suiciently to provide heat insulating air spaces between the strips. It has been found advantageous to space these strips so that an air space of approximately of an inch will be provided between adjacent strips.
A suitable form of metal foil heat insulating strip for use in the metal baskets as described above, is shown in Fig. 5.v The metal foil strip 23 which is preferably made of thin aluminum foil is crumpled by hand or any suitable means to form a very large number of irregular surfaces illustrated at 24. This formation may be produced by simply wadding and lightly compressing the flat sheet of metal foil by hand and then pulling out the crumpled sheet to its new effective length. It will be noted that the crumpling of the sheet reduces its width. The purpose of the crumpling of the sheet is to provide surfaces of various heights and formations so that when the sheets are laid side by side in the metal basket any contact between sheets will be only point contact instead of continuous flat surface contact. This arrangement insures a minimum amount of heat transfer between adjacent sheets. This feature is illustrated in Fig. 3, wherein the several sheets of crumpled metal foil 24 are shown as having only point contact with each other.
The method of applying the heat insulating metal panels shown in Figs. 1 to 4 is illustrated in Fig. 6. The panels are arranged vertically as shown in the latter gure and joined together in sufficient number to cover the entire exposed surface of the equipment generally shown at 25. Adjacent panels are fastened together by means of the metal clips I5 and bolts Il as described above. Tightening of these bolts brings the clincher edges I4 of adjacent panels near' eacli other. A clincher strip 26 shown in Fig. 8 is then driven down over the clincher edges I4 of each'of the abutting jackets II thereby securely locking the two panels together and in proper position. This clincher strip 26 is easily removable and replaceable, by means of a notch 2B in the clincher edge I4, which notch is 1ocated at the junction ofclincher strips 26. The strip 26 serves several functions including locking the two panels together, forming a waterproof and heat insulating joint therebetween and maintains the joined panels in their proper posi# tions, preventing buckling or sagging.
At the time` the panels are being installed in the manner described above, compressible and expansible gaskets (notl shown). around the edges of eachl panel as they are erected. These gaskets may be made of any suitable material such as forY example, glass wool, mineral wool, rock wo'ol, lead Wool, mattedasbestos, etc. The' expanded metal basket I0 will securely maintain4 the gasket in position and vat the are placed same time permit any necessary expansion of the i' gasket into the panel without materially increasing its density, thereby maintaining its original is permitted at each panel joint. The clincher' are easily removable and replaceable one unitat a time and independent from any other unit.
The metal foil inner lining 20 provided in each of the baskets serves to reflect the majority of the radiant heat back against the surface on which the insulation is applied, resulting in quick preheating or quick cooling of the surface vas desired. The inside face of the metal jacket II may be covered with aluminum paint or with foil coated insulating material or aluminum foil, as suggested above, to provide a heat reective surface which will reflect the major portion of the radiant heat that may be carried by convection currents through the surrounding edges of the insulation in the panel back toward its source.
This feature effects minimum heat transfer at all joints.
The outer exposed surface of the metal jacket Il, as well as all surfaces of the metal basket Il) are preferably coated with aluminum paint applied in such a manner that it will withstand high temperatures without disintegration or discoloration. These aluminum coated surfaces act not only as reflectors of radiant heat on the inside of the panel toward the surface being insulated but they also insure a v ery low emission of radiant heat on the outside surface of the tank.'
In summer daylight operation the outside aluminum painted surfaces will serve to reect a large portion of the incident solar radiant heat.`
It will be understood that the materials., sizes and modes of construction` described hereinabove, by Way of example to illustrate the general principles of this invention may be changed to meet varying heat insulating requirements without departing from the scope of the invention. Some of the novel features of the heat insulating panels of this invention are set forth in the appended claims.
What is claimed is:
l. A heat insulating metal panel comprising an outer sheet metal cover, a substantially rigid reticulated metal basket having one normally open side and being attached to said metal cover at peripheral points along the edges of said normally open side by means of metal connectors which space said reticulated metal basket from said sheet metal cover to provide a heat insulating dead air space therebetween which substantially prevents flow of heatlbetween said cover and basket, a metallic foil, basket shaped, member located within said basket and forming an air impervious heat' reflective lining for said reticulated basket and providing an effective heat insulating dead air space within said basket such that flow of air into and out of said basket is substantially prevented, and heat insulating material loosely arranged within said metal foil, basket-shaped member so as to divide said dead air space into a plurality of smaller dead air spaces which substantially prevent transfer of heat through said basket.
2. A heat insulating panel as defined in claim l in which the connectors that connect the reticulated metal basket and sheetl metal cover are angular shaped metal clips .Welded to said basket and cover.
- LEON T. SIBLEY.
ROY J. SCOII.