SYNTHETIC GASKET MATERIALS FOR USE IN HIGH PRESSURE HIGH TEMPERATURE PRESSES

Abstract

A gasket material for high pressure high temperature presses, comprising: a proportion of a clay mineral a proportion of a hard material for increasing the viscosity of the clay mineral a proportion of a binder selected from the group of borate binders, phosphate binders, and mixtures thereof.

Claims

1. A gasket material for high pressure high temperature presses, comprising: i. a proportion of a clay mineral ii. a proportion of a hard material for increasing the viscosity of the clay mineral iii. a proportion of a binder selected from the group of borate binders, and mixtures of borate binders and phosphate binders.

2. The gasket material as claimed in claim 1, in which the proportions of clay mineral to hard material lie in the respective ratios 1-10:10-1.

3. The gasket material as claimed in claim 1, in which the proportion of binder to the combined amount of clay mineral and hard material lies in the respective ratios 1:1-100.

4. The gasket material as claimed in claim 1, in which the total amount of clay mineral, hard material, and binder lies in the range 70-100 wt % of the gasket material.

5. The gasket material as claimed in claim 1, comprising: TABLE-US-00005 Clay mineral 60-90 wt % Hard material 5-35 wt % Binder 5-25 wt %

6. The gasket material as claimed in claim 5, comprising 61 wt % or more clay mineral.

7. The gasket material as claimed in claim 6, comprising: TABLE-US-00006 Clay mineral 65 4 wt % Hard material 15 5 wt % Binder 5-25 wt %

8. The gasket material as claimed in claim 1, in which the clay mineral is selected from the group consisting of akermanite, bertandite, kaolinite, pyrophyllite, prehnite, pyrope, scolecite, serpentine, talc, zoisite, and mixtures thereof.

9. The gasket material as claimed in claim 1, in which the hard material is selected from the group consisting of silica, zircon, garnet, silicon carbide, boron carbide, alumina, zirconia, kyanite, mullite, and mixtures thereof.

10. A method of making a gasket material as claimed in claim 1, comprising the steps of dispersing the solid constituents, blending them, and pressing.

11. The method as claimed in claim 10, in which dispersing and blending the solid constituents comprises dispersal of the solid constituents in a solution to form a suspension, and spray drying the suspension.

12. The method as claimed in claim 10, in which the solid constituents are granulated.

13. A gasket formed from the gasket material of claim 1.

Description

EXAMPLES

[0034] In the following examples: [0035] talc was used as the clay mineral [the commercial grade Micron 554 from Emerys. It is a 325 mesh material with a mean particle size of 3 microns]; [0036] 220 mesh silicon carbide was used, although finer material is preferred; [0037] examples #1 and #3 are prophetic examples.

[0038] Powders of examples #2, #4, and #5 indicated below were manufactured by using hot water to dissolve the boric acid, then adding the other ingredients, then drying to form a powder.

[0039] This powder was subsequently pressed in a laboratory uni-axial Carver press to a pressure of about 103 MPa (15,000 psi) to form sample discs for evaluation.

[0040] The discs prepared were found to be consolidated.

[0041] Assessment of the brittleness of the discs by crushing in a mortar and pestle back to a pressable powder showed that higher clay content (in the case of these examples, talc) improved the materials, in that Examples #4, and #5 appeared more brittle than Example #2.

TABLE-US-00003 #1 #2 #3 #4 #5 Talc 65% 65% 45% 45% 60% B.sub.4C 15% 0% 25% 0% 0% SiC 0% 15% 0% 25% 20% Boric acid 20% 20% 30% 30% 20% Total: 100% 100% 100% 100% 100%

[0042] For phosphate binders prospective embodiments include:

TABLE-US-00004 Dry mix Talc 70% 70% 70% 70% B.sub.4C 20% 20% 0% 30% SiC 10% 10% 30% 0% Total dry mix 100% 100% 100% 100% Phosphate binder (as % of dry mix) 10% 15% 15% 15%

[0043] These examples and prospective embodiments are indicative of materials that may be made in accordance with the invention and the invention is not restricted thereto.