Thermoplastic liner pipe for potable water

A process for continuously producing a glass-reinforced plastic potable watery pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick comprising a coextruded multi-layer thermoplastic film comprising a polyethylene film together with a terpolymer film comprising polyethylene, an acrylic ester, and maleic anhydride;
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.

A process for continuously producing a glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick;
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset polyester resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said inner layer comprising a coextruded multi-layer thermoplastic film comprising a polypropylene based film as the innermost layer, a polyamide based film, and having a very thin layer of terpolymer between the polypropylene based film and the polyamide based film, and a very thin layer of terpolymer between the polyamide based film and the outer layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.

A process for continuously producing a glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick, the first application means comprising one or more extrusion means equipped with a film die means positioned in close proximity to said mandrel surface and from which thin melt films of said thermoplastic material, less than 1 mm thick, are extruded onto said mandrel to form an essentially impermeable thermoplastic inner layer, said inner thermoplastic layer comprising a coextruded multi-layer thermoplastic film comprising a polyethylene film together with a terpolymer film;
• contemporaneous with the application of said inner layer, applying glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.

A process for continuously producing a glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferential and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick, the first application means comprising one or more extrusion means equipped with a film die means positioned in close proximity to said mandrel surface and from which thin melt films of said thermoplastic material, less than 1 mm thick, are extruded onto said mandrel to form an essentially impermeable thermoplastic inner layer, said inner thermoplastic layer comprising a coextruded multi-layer thermoplastic film comprising a polyethylene film together with a terpolymer film comprising polyethylene, an acrylic ester, and maleic anhydride;
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed as it is moved axially along the mandrel.

A process for continuously producing a glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick, the first application means comprising one or more extrusion means equipped with a film die means positioned in close proximity to said mandrel surface and from which thin melt films of said thermoplastic material, less than 1 mm thick, are extruded onto said mandrel to form an essentially impermeable thermoplastic inner layer, said inner thermoplastic layer comprising a coextruded multi-layer thermoplastic film comprising a polypropylene based film as the innermost layer, a polyamide based film, and having a very thin layer of terpolymer between the polypropylene based film and the polyamide based film, and a very thin layer of terpolymer between the polyamide based film and the outer shell comprised of a coextruded multi-layer thermoplastic film comprising a polyethylene film together with said terpolymer film comprising polyethylene, an acrylic ester, and maleic anhydride;
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.

A process for continuously producing a glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick the first application means comprising one or more conveyance means which can feed one or more pre-formed films of said thermoplastic materials, less than 1 mm thick, onto said mandrel to form an impermeable thermoplastic layer, and heating means to weld said films into place, said inner thermoplastic layer comprising a coextruded multi-layer thermoplastic film comprising a polyethylene film together with a terpolymer film,
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.

A process for continuously producing glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick the first application means comprising one or more conveyance means which can feed one or more pre-formed films of said thermoplastic materials, less than 1 mm thick, onto said mandrel to form an impermeable thermoplastic layer, and heating means to weld said films into place, said inner thermoplastic layer comprising a coextruded multi-layer thermoplastic film comprising a polyethylene film together with a terpolymer film comprising polyethylene, an acrylic ester, and maleic anhydride;
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.

A process for continuously producing a glass-reinforced plastic potable water pipe with an ultra-thin thermoplastic inner layer and thermoset plastic outer shell, comprising the steps of:

• conveying, in a semi-molten or softened form, at least one thin film of thermoplastic material, onto a mandrel circumferentially and axially to the mandrel by a first application means to form an inner layer less than 1 mm thick the first application means comprising one or more conveyance means which can feed one or more pre-formed films of said thermoplastic materials, less than 1 mm thick, onto said mandrel to form an impermeable thermoplastic layer, and heating means to weld said films into place, said inner thermoplastic layer comprising a coextruded multi-layer thermoplastic film comprising a polypropylene based film as the innermost layer, a polyamide based film, and having a very thin layer of terpolymer between the polypropylene based film and the polyamide based film and a very thin layer of terpolymer between the polyamide based film and the outer layer;
• contemporaneous with the application of said inner layer, applying a glass-reinforced thermoset plastic resin suitable for use as pipe shell laminate directly over the advancing inner layer circumferentially and axially to the mandrel and further along the mandrel, by a second application means, thereby forming an outer layer which adheres to said inner layer;
• said outer and inner layer forming a completed pipe;
• and
• curing the completed pipe as it is moved axially along the mandrel.