Shotcrete accelerator injection apparatus and method

Claim 3

The method of claim 1 wherein the shotcrete accelerator is supplied at a substantially constant rate of flow and pressure.

Claim 4

The method of claim 2 wherein said rate of flow and the pressure of said shotcrete accelerator are adjustable.

Claim 5

The method of claim 3 wherein the compressed air is supplied at a substantially constant pressure and rate of flow.

Claim 6

The method of claim 4 wherein the pressure and rate of flow of said compressed air are adjustable.

Claim 7

The method of claim 5 wherein said shotcrete accelerator is supplied from a source comprised of a reservoir of shotcrete accelerator and a positive displacement air driven pump having an accumulator connected to its output.

Claim 8

The method of claim 6 wherein said pump is driven by an external source of compressed air from about 25 pounds per square inch to about 150 pounds per square inch supplied through an adjustable pressure regulator.

Claim 9

Apparatus for applying shotcrete comprised of: a source of shotcrete under pressure; a source of shotcrete accelerator; first and second sources of compressed air; an air driven positive displacement pump connected to said first source of compressed air to be driven thereby and positioned and connected to take a suction from said source of shotcrete accelerator and to supply shotcrete accelerator under pressure at its output; an accumulator having an inlet and an outlet, said inlet being connected to receive the output of said pump; a shotcrete applicator connected to the source of shotcrete to receive shotcrete under pressure therefrom; an accelerator injection manifold positioned along the length of said applicator, said manifold having: a first inlet connected to the outlet of said accumulator to receive shotcrete accelerator therefrom, a second inlet connected to said second source of compressed air to receive compressed air therefrom, a body in which said compressed air and said shotcrete accelerator are intermixed, and a plurality of outlets connected to said applicator to inject the mixture of compressed air and shotcrete accelerator into the shotcrete in said applicator.

Claim 10

Apparatus for applying shotcrete comprised of: a source of shotcrete under pressure; a source of shotcrete accelerator; first and second sources of compressed air; an air driven positive displacement pump connected to said first source of compressed air to be driven thereby and positioned and connected to take a suction from said source of shotcrete accelerator and to supply shotcrete accelerator under pressure at its output; an accumulator having an inlet and an outlet, said inlet being connected to receive the output of said pump; a shotcrete applicator connected to the source of shotcrete to receive shotcrete under pressure therefrom; an accelerator injection manifold positioned along the length of said applicator, said manifold having: a first inlet connected to the outlet of said accumulator to receive shotcrete accelerator therefrom, a second inlet connected to said second source of compressed air to receive compressed air therefrom, a body in which said compressed air and said shotcrete accelerator are intermixed, and a plurality of outlets connected to said applicator to inject the mixture of compressed air and shotcrete accelerator into the shotcrete in said applicator.

Claim 11

The apparatus of claim 8 wherein said manifold has: a first valve connected at said first inlet to regulate and stop the flow of said shotcrete accelerator; a second valve connected at said second inlet to regulate and stop the flow of said compressed air; and two said outlets positioned approximately diametrically opposite each other.

Claim 12

The apparatus of claim 9 wherein said first and second sources of compressed air is compressed air from about 25 pounds per square inch to about 150 pounds per square inch pressure.

Claim 13

The apparatus of claim 10 further comprising an adjustable pressure regulator connected to receive compressed air from said first source thereof and to supply regulated compressed air to said pump, said regulator having filter means to filter said compressed air regulator means to regulate the flow of said compressed air to said pump and in turn the speed and output thereof, and lubricator means to inject lubricant into said regulated compressed air to lubricant said pump.

Claim 14

The apparatus of claim 11 wherein said pump has an exhaust to exhaust used compressed air and a muffler affixed to said exhaust to quiet said exhaust, said source of shotcrete accelerator is a conventional drum filled with said accelerator, and said pump is positioned on top of said drum and said pump suction is an adjustable tube extending substantially to the bottom of said drum.