US 5,766,525 A · Methods for manufacturing articles from sheets of unhardened hydraulically settable compositions

Abstract

Methods and systems for readily and economically manufacturing hydraulically settable articles, particularly containers, from microstructurally engineered hydraulically settable mixtures wherein the mixture is extruded into a sheet that is feed through a plurality of sets of rollers so as to form the sheet into the desired thickness. The sheet is then pressed between a male die of a desired shape and a female die having a substantially complimentary configuration of the male die shape to immediately fashion a portion of the sheet into a form stable shape for the desired article. To assist in imparting form stability, the dies can be heated or cooled. Once the article has obtained form stability, the article is removed from the dies and dried under heated air to gain strength. The article can then be cut from the sheet and receive printing or a coating, if desired, prior to packaging, shipping, and use.

Claims185

Dependent claims

A method for manufacturing an article having a hydraulically settable matrix, the method comprising the steps of:

(a) mixing together a hydraulically settable binder, a rheology-modifying agent, an inert inorganic aggregate filler and water in order to form a hydraulically settable mixture that is characterized in that the mixture can be passed between a pair of counter-rotating reduction rollers while in a green state to form a sheet having a thickness less than about 3 mm the inert inorganic aggregate filler having a concentration greater than about 50% by weight of the hydraulically settable binder;
(b) passing the hydraulically settable mixture between a pair of counter-rotating reduction rollers while in the green state to form a cohesive and coherent sheet having a thickness less than about 3 mm, the sheet having sufficient cohesive strength while still in the green state and prior to pressing and hardening such that the sheet does not rupture as the sheet exits the reduction rollers thereby forming a coherent sheet;
(c) pressing at least a portion of the sheet while in the green state into a desired shape of the article, the article gaining form stability in less than about one minute after first being pressed into the desired shape;
and
(d) allowing the pressed portion of the sheet to harden into the desired shape of the article.

2 more elements

A method for manufacturing an article having a hydraulically settable matrix, the method comprising the steps of:

(a) mixing together a hydraulically settable binder, rheology-modifying agent, inert inorganic aggregate filler, and water in order to form a hydraulically settable mixture that is characterized in that the mixture can be passed between a pair of counter-rotating reduction rollers while in a green state to form a sheet having a thickness less than about 3 mm, the inert inorganic aggregate filler having a concentration greater than about 50% by weight of the hydraulically settable binder;
(b) passing the hydraulically settable mixture between a pair of counter-rotating reduction rollers while in the green state to form a cohesive and coherent sheet having a thickness less than about 3 mm and sufficient cohesive strength to be elongated by at least about 0.5% while still in the green state and prior to pressing and hardening such that the sheet does not rupture as the sheet exits the reduction rollers;
(c) pressing at least a portion of the sheet while in the green state into a desired shape of the article;
and
(d) allowing the pressed portion of the sheet to harden in the desired shape of the article.

2 more elements

A method for manufacturing a container having a hydraulically settable structural matrix, the method comprising the steps of:

(a) mixing together a hydraulically settable binder, an inert inorganic aggregate filler, a rheology-modifying agent and water to form a hydraulically settable mixture that is characterized in that the mixture can be passed between a pair of counter-rotating reduction rollers while in a green state to form a sheet having a thickness less than about 3 mm, the inert inorganic aggregate filler having a concentration greater than about 50% by weight of the hydraulically settable binder;
(b) passing the hydraulically settable mixture between a pair of counter-rotating reduction rollers while in the green state to form a cohesive and coherent sheet having a thickness less than about 3 mm and sufficient cohesive strength while still in the green state and prior to pressing and hardening such that the sheet does not rupture as the sheet exits the reduction rollers;
(c) pressing at least a portion of the sheet between a heated male die and a heated female die in order to mold the mixture into a desired shape of the container such that the container gains form stability in less than about one minute after first being pressed into the desired shape;
(d) removing the heated male die and the heated female die from the hydraulically settable mixture in the desired shape of the container after the container has achieved form stability;
and
(e) drying the form stable container to form the hydraulically settable structural matrix.

3 more elements

A method for manufacturing a container having a cementitious structural matrix, the method comprising the steps of:

(a) mixing together a cellulose fiber, a lightweight inorganic aggregate, a rheology-modifying agent, a hydraulic cement and water to form a cementitious mixture that is characterized in that the mixture can be passed between a pair of counter-rotating reduction rollers while in a green state to form a sheet having a thickness less than about 3 mm the lightweight inorganic aggregate having a concentration greater than about 50% by weight of the hydraulic cement;
(b) applying a vacuum to the cementitious mixture to extract air from the mixture;
(c) extruding the cementitious mixture through a die to form the cementitious mixture into a cohesive and coherent sheet having sufficient cohesive strength to be elongated while the mixture is in the green state without rupturing the sheet;
(d) feeding the extruded sheet between a plurality of pairs of heated counter-rotating reduction rollers that incrementally elongate and decrease the thickness of the sheet as the sheet passes from one pair of reduction rollers to a next pair of reduction rollers, the heated reduction rollers imparting form stability to the sheet such that the sheet does not rupture as the sheet exits the reduction rollers;
(e) pressing at least a portion of the sheet between a heated male die and a heated female die in order to mold the portion of the sheet into a desire shape of the container, the container achieving form stability in less than about one minute after first being pressed into the desired shape of the container;
(f) removing the heated male die and the heated female die from the container within a period of time less than about one minute after first pressing the portion of the sheet into the desired shape, the molded container having achieved form stability within the time period so as to be self-supporting independent of the male die and the female die;
and
(g) drying the container to form the cementitious structural matrix.

5 more elements

Dependencies are inferred from the claim text.

Methods for manufacturing articles from sheets of unhardened hydraulically settable compositions

Life of this patent

Methods for manufacturing articles from sheets of unhardened hydraulically settable compositions

Life of this patent

Abstract

Claims185