Semi-continuous two-pack process for casting solid propergol paste
View Patent ↗A process for casting propellant paste into a mould to manufacture a block of solid propellant includes first mixing two groups of components briefly at low pressure, mixing the two groups of components at high pressure, and casting the mixture in a mould. The first group of components represents about 80% to about 99% of the finished product and essentially comprises a liquid prepolymer, at least one pulverulent solid charge and some of the various additives of the propellant paste. The second group of components represents about 20% to about 1% of the finished product and comprises the crosslinking agent and the rest of the additives.
1. A semi-continuous two-pack process for making a block of solid propellant, comprising:
mixing a first group of components and a second group of components to form a mixture;
casting the mixture in a mould;
wherein the first group of components represents about 80% to about 99% of the finished product and comprises essentially a liquid polymer, at least one pulverulent solid charge and at least one additive;
wherein the second group of components represents about 20% to about 1% of the finished product and comprises a crosslinking agent; and
wherein the first group of components and the second group of components are separately mixed prior to the mixing step.
2. The process according to claim 1 , wherein the first group of components represents about 90% to about 99% of the finished product and the second group of components represents about 10% to about 1% of the finished product.
3. The process according to claim 1 , wherein the second group of components comprises the crosslinking agent and at least one additive.
4. The process according to claim 1 , wherein the mixing step comprises:
setting the ratio of the first group of components to the second group of components to the right amount, by means of precise metering of the two groups of components;
mixing the first group of components and the second group of components under low pressure to form the mixture;
passing the mixture into a buffer tank;
homogenization mixing of the mixture.
5. The process according to claim 4 , wherein the mixture is passed into a buffer tank between the mixing and homogenization mixing steps.
6. The process according to claim 4 , wherein the mixing step is performed in a static mixer and the homogenization mixing step is performed in a static mixer.
7. The process according to claim 4 , wherein the mixing step is performed at a pressure between 0.006 MPa and 1 MPa.
8. The process according to claim 4 , wherein the homogenization mixing step is performed at a pressure between 2 MPa and 2.5 MPa.
9. The process according to claim 8 , wherein the homogenization mixing step is performed at a curing temperature of between 20° C. and 80° C.
10. The process according to claim 1 , wherein the mixing step is performed in a static mixer at high pressure.
11. The process according to claim 10 , wherein the mixing step is performed at a curing temperature of between 20° C. and 80° C.