PL103973B1 - METHOD OF PERFORMING THERMAL INSULATION - Google Patents

Description

The subject of the invention is a method of carrying out thermal insulation.

The increasing consumption of natural gas requires increasing its transport in liquid form, w low temperature, for example -160 ° C. Trans Such cars are made under pressure, in isolation thermally insulated spherical tanks with a capacity of carrying 135,000 m3 or more, placed on the kach.

There are known methods of producing thermal insulation this is the lamination of the tanks.

British Patent No. 945,261 there is a method of thermal insulation of the tank nika, the two individual layers of which are together joined with a hardened glue a solution of polyurethane elastomer and polyiso- cyanate.

British Patent No. 1,326,298 describes sticking a layer of expanded polystyrene, polyurethane retane, polyvinyl chloride or duromer from others material, a hardening adhesive the mass resulting from the reaction of the clay mixture a ceride containing OH groups and a polyether diol with a diisocyanate.

However, the thermal insulation produced on the tank It is highly susceptible to these methods on a pecan. The layer that functions as an adhesive does not prevents cracking of the sticky layer. How it has been found in these known embodiments the adhesive bond does not stop it from spreading lo cracks formed through the laminate due to the large temperature difference of 20 ° C - 160 ° C ^ occurring between the outer and inner half top thermal insulation. After cooler on the side of the tank there is a very significant increase the fragility of the laminate, and because the steel tank or aluminum shrinks after setting insulating layer, in the insulating layer there is puja significant transverse shear stresses, which causes the process to unfold over time cracks and leads to partial damage thermal insulation, thus facilitating the glass the transfer of heat from the surrounding atmosphere to tank.

The object of the invention is to overcome these disadvantages and especially finding a way to produce crack-resistant thermal insulation.

It was found that the cracking process of the insulation layer thermal action begins in cold air chirps and then spreads perpendicular to an insulated element, it was also found that that the process of spreading can cracks can be prevented by the use of an intermediate layer it, placed on a layer of urethane foam, at some distance from a cold surface tank, thus dividing thermoinsilations from urethone foam in two layers. Application an additional intermediate layer or layer running crackling, thus splitting the foam urethane in several layers. The layer prevents 103 9733 103 g73 4 the crackling is positioned transversely in the table to the potential direction of cracking and there is parallel to the cool surface. Favorable the layers are applied by spraying though other ways of applying them are also possible.

The insulating layers are made up of one or more the spray head is moved several times.

According to the invention, the method of making the insulation thermal is the production of the first temperature stiff or semi-rigid urethane foam input, then on production on the former a second layer to prevent cracking made of urethane elastomer, by applying a copper liquid urethane elastomer prepolymer ™ ygfy 7flwifi; fljacegfi free isocyanate groups ofaA ft ^ and ^ miny luj} polyol then on a layer anti-crack another is formed again a third layer of flexible or semi-rigid foam n ^ 'W £ tsnew * located on the opposite side of the value anti-cracking than the first layer the third layer is the second the urethane foam layer is formed by application on the anti-cracking layer, urethane reaction mixture and then leaving this mixture to foam and hardening.

The elastomer is formed by liquid reactions the urethane elastomer prepolymer thereof contains his free isocyanate groups from polyamine or with a polyol. An elastomer layer is preferably used not formed by the hexamethylene double reaction toluene isolation or diisolate or pure methane diphenyl diisocyanate with a mixture of with a polyether liol or with a polyester polyol, to produce a prepolymer containing several free isocyanate groups. This prepolymer then reacts with polyamine, such as meth- lenp- ^ chloroaniline or methylene dianiline, or. with a polyol such as butanediol.

According to the invention, further can be added layers of elastomer and urethane foam to form multilayer thermal insulation, whereby the first layer of foam may be applied directly on an insulated element or on a temperature of the elastomer material directly deposited on it element.

To create an anti-cracking layer Preferably, an elastomer based on the reaction products of organic isocyanates with with polyether or polyester polyols, rajacymi a few unedrafted free isocyanate groups. It is used as isocyanates are preferably hexamethylenediisocyanate or toluene diisocyanate or pure diphenylmethate taepclw ^ CiC & Ly- Piepojimer elastomer ry ur.etaAQwre ^ 9 then reacts with polyamine aromatic ,, te ^ ka like rnet ^ lenooTtp ^ inchloroani- Una lily, methylene polyurethane, or optionally z l ^^ cJk ^ la ^ iania nxz ^ a ^ wio.ny ^ b in: drawing, n ^ ktgr ^ fig ^ 1 pr ^ e ^ taws, ^ chinels of the wall WS ^ St iefe ^ S ^ mh ^ ffl ^ RBIl s ^ s and Fig. 2 is a section of the wall of the reservoir indoor five-layer thermal insulation. The wall the tank surface 10 is covered with a stiff layer 11 urethane foam or semi-rigid, layer 12 elastomer, layer 13 made of urethane foam, layer 14 made of elastomer and layers 15 and 16 made of urethane foam. Layers 15 and 16 may have form of a uniform single layer. Each of urethane layers 11, 13, 15, 16 can be formed by sliding the head once spray gun.

In one embodiment, spherical liquefied natural gas tank made of aluminum or steel containing 9% nickel thermally insulated steel, semi-rigid or rigid on the urethane foam applied to the outside reservoir surfaces, in several layers through spraying, each layer is foamed and solidified before applying the layer next.

Foam, thanks to its low thermal conductivity has proven to be an ideal preventive material gas losses by evaporation, although permitted there is some evaporation through the control outlet to keep the temperature of the liquid gas low zu.

To ensure adequate insulation, sand it is applied in layers with a thickness of glue down to 25.4-50.8 mm until complete the thickness of the insulating material is about 203-254 mm.

Thickness of the layer or each layer of elastomer is 0.1 mm, for example, but may also be a hundred there are different thicknesses depending on conditions using.

Efficiency of an elastomer layer as a layer anti-cracking has been found to experimentally by hardening the composite layers made of elastomer foam on the surface of a small tank a cloth placed in a frame and poured over it insulating surface with liquid nitrogen at a temperature at —196 ° C. Under these conditions, it showed 40 spots in the corner of the foam surface; stated it was said that this crack does not spread but through the elastomer layer, a plug is placed between the first and second layers of foam.

It was also found that the elastomer strands contain 45 immersed in liquid nitrogen within 24 hours can be bent without cracking, the thickness of the test sample ki was about 3.2 mm. Sample Extension at tensile stress at -160 ° C it was in the order of 15-20% - 50 In situ installation of thermal insulation on the element subjected to insulation is not necessary.

Insulation can be done by applying the first wear layer made of a foaming component, on a completely different substrate by single 55 move the spray head, then even not using a spray head to apply the elastomer layer and then one or with a few movements of the head, he sprays a further layer of foam. After the foam solidifies " 60 The insulation thus maintained is cut into strands of response the better and puts it on the insulated element. ? {cheat, some specific examples were drunk the increase of the elastomer layer according to the invention lazku. Example I. The elastomer was prepared for 103,973 mixing 100 parts by weight of liquid pre-mixture polymer containing urethane elastomer 6.3% of the free isocyarate groups were produced by the reaction of polytetromethyl glycol ether flaxseed with toluene diisocyanate, with 19.5 cc weights of methylene or di-chloroaniline using 0.6 parts by weight of adipic acid as a catalyst. We get the elastomer used after 15 minutes have elapsed.

An elastomer layer about 0.1 mm in applied to the outer surface of the spherical tank. After it solidifies into an elastomeric layer A layer of urethane foam with a thickness of 38.1 mm, and this layer was in turn applied another layer of elastomer about 15 mm thick 0.1 mm, after which further layers of foam were applied until the total thickness of the insulation is achieved about 254 mm.

Example II. The elastomer was made by mixing at room temperature, 100 cg§ci 20 by weight of a prepolymer, such as pcdans v example I with 14.5 parts by weight of methyl- nodvuaniline. Due to this, this reaction runs quickly, both ingredients have been brought to spray head separately with pump 25 py.

Example III. The elastomer was made by subjecting 100 parts by weight of the prepolymer to the description - * in Example 1 of the reaction with 0.3 parts by weight of butanediol -1.4. in Example IV. The prepolymer was made by mixing tetrapolymethylene glycol ether with di- with diphenylmethane isolate until obtaining 0.3% of free isocyanate groups. As the elastomer used was the same elastomer as given 35 in examples I-III.

Example 5 A prepolymer was prepared by mixing of polyethylene propylene glycol adipate- with toluene diisocyanate until it is reached scans 0.3% of free isocyanate groups. As 40 elastomer, an elastomer such as that given in examples I-III.

Example VI. The prepolymer was made by mixing polyethylene glycol adipate flaxseed with diphenylmethamodiisocyanate and 45 to obtain 0.3% of free isocyanate groups An elastomer such as that described herein was used as the elastomer sano in examples I-III.

Example VII. The prepolymer was made by mixing polypropylene glycol ether with 50 with toluene diisocyanate until 0.3% free isocyanate groups. The elastomer was made by as in examples I-III.

The prepolymer is not limited to the content 0.3% isocyanate groups, yes 55 that and other values while maintaining such pro¬ serving in the elastomer components to make the elastomer it did not contain free isocyanate groups.

Depending on the conditions in which thermal insulation mica is to be used, uireta-60 foam is used new rigid or semi-rigid. At temperatures in the order of -160 ° C, very stiff foam is not water, in which case foam is better intermediate between rigid and semi-rigid. Engrossed Rigid and semi-rigid foam are terms relative to- • * by specialists in this field day, their task is to assess a greater or lower degree of desired insulation flexibility in conditions of its use. Urethane foam is made by mixing 80 parts by weight polyols with an equivalent weight of 108, obtained by propoxylating the glycine mixture cerine and sucrose, 20 parts by weight of polyol, with the equivalent weight of 350, obtained by prepoxylation of glycerin, 2 parts by weight organosilicon surfactant- it, 1 part by weight of formic acid with three ethylenediamine, 20 parts by weight of phosphate tri-fj-chloroethyl and 15 parts by weight of tri- chlorofluoromethane.

The second ingredient is the crude diisocy- ni.n diphenylmethane.

Claims (10)

Patent claims 1. A method of making thermal insulation, which consists in producing a first layer of rigid or semi-rigid urethane foam, is followed by producing a second anti-cracking layer on this first layer, characterized in that the anti-cracking layer is formed of an elastomer urethane by applying a mixture of a liquid urethane elastomer prepolymer containing free isocyanate groups and a polyamine or polyol, and a third layer is formed on the anti-cracking layer, constituting a second layer of rigid or semi-rigid urethane foam, which is placed on the opposite side. an anti-crack layer than the first layer, the third layer being produced by applying an anti-cracking urethane elastomer layer to the urethane reaction mixture and then allowing the mixture to foam and cure. 2. A method of thermal insulation according to claim 1, characterized in that a prepolymer is used, prepared by reacting toluene diisocyanate with a polyol-based polyether. 3. The method of thermal insulation according to claim The process of claim 1, wherein the prepolymer is prepared by reacting toluene diisocyanate with a polyol-based polyester. 4. The method of thermal insulation according to claim The process of claim 1, wherein the prepolymer is prepared by reacting diphenylmethane diisocyanate with a polyol-based polyether. 5. The method of thermal insulation according to claim The process of claim 1, wherein the prepolymer is prepared by reacting diphenylmethane diisocyanate with a polyol-based polyester. 6. Method of thermal insulation according to claim .1, characterized in that a polyether tetramethylene glycol is used as the polyether on the polyol phase. 7. The method of thermal insulation according to claim The process of claim 1, wherein the polyether-based polyether 103 973 is a polyester of adipic acid and of ethylene and propylene glycol. 8. Method of thermal insulation, according to claim The process of claim 1, wherein butanediol is used instead of the polyol. 8 9. Method of thermal insulation according to claim The process of claim 1, wherein the polyamine is bis (aminophenyl) methane. 10. The method of thermal insulation, according to claim The process of claim 1, wherein the polyamine is bis- (3-chloro-4-aminophenyl) methane. FteoI I 7L PZGraf. Koszalin D-772 115 Price