1. A method for manufacturing a three-dimensional metal casting mold, comprising:
a) providing a plurality of silica sand particulates that are substantially free of binder material;
b) coating at least a portion of a surface of each of the plurality of silica sand particulates with an activation agent;
c) contacting a pre-selected portion of the particulates having the activation agent present upon the particulates with a binder material that is activatable by the activation agent pursuant to which binder material is contacted with the particulates no earlier than when the binder material first contacts the activation agent;
d) at least partially hardening the binder material, crosslinking the binder material to itself and coupling adjoining particulates to each other with the binder material for forming a layer of the three-dimensional metal casting mold by the reaction between the binder material and the activation agent; and
e) repeating the steps (a)-(d) to form the remainder of the three-dimensional metal casting mold;
wherein the binder material includes molecules that cross-link among each other and the binder material is selected from the group consisting of phenol resin, polyisocyanate, polyurethane, epoxy resin, furane resin, polyurethane polymer, phenolic polyurethane, phenol-formaldehyde furfuryl alcohol, urea-formaldehyde furfuryl alcohol, formaldehyde furfuryl alcohol, peroxide, polyphenol resin, resol ester and mixtures thereof, and
wherein the binder material is present at a concentration of less than 2 weight percent based on the total weight of the mold.
2. The method of claim 1 wherein the activation agent is selected from the group consisting of acids, amines, alcohols, ketones, salts, and mixtures thereof.
3. The method of claim 2 wherein the binder material is selected from the group consisting of epoxy resin, furane resin, and mixtures thereof.
4. The method of claim 3 wherein heat is applied prior to or during the hardening step.
5. The method of claim 3 wherein the activation agent coating step (b) is done by a step selected from brushing, rolling, blading, spraying, plating or a combination thereof.
6. The method of claim 3 wherein the binder material contacting step (c) includes dispensing the binder material through a drop-on-demand dispenser.
7. The method of claim 1 wherein the viscosity of the binder material at 20\xb0 C., ranges from 5 to 60 cps.
8. The method of claim 1, further comprising a step of re-using particulates that are not contacted with the binder material.
9. The method of claim 8 wherein the binder is an organic material, heat is applied prior to or during the hardening step, and the activation agent includes one or more acids selected from the group consisting of sulfuric acid, sulfonic acid, phosphoric acid, hydrochloric acid, and nitric acid.
10. The method of claim 9 further comprising pouring a material, selected from a metal or a plastic, in a molten state, into a resulting mold to form a part using the mold.
11. The method of claim 9 wherein the particulates are foundry sand particles, wherein 80 percent by volume of the particles have a diameter from 90 \u03bcm to 210 \u03bcm.
12. The method of claim 9, further comprising forming a core in the mold.
13. A method for manufacturing a three-dimensional metal casting mold, comprising:
a) coating a plurality of individual sand particles that are substantially free of binder material with an activation agent;
b) dispensing an organic activatable resin binder material through a print head over preselected portions of the sand particles that include the activation agent for contacting the activation agent, pursuant to which the dispensed binder material is contacted with the particles no earlier than when the binder material first contacts the activation agent;
c) reacting at a temperature of about 20\xb0 C. to about 30\xb0 C. the binder material with the activation agent for at least partially hardening the binder material, crosslinking the binder material to itself, and coupling adjoining particles to each other with the binder material, for forming a layer of the three-dimensional metal casting mold;
d) repeating the steps (a)-(c) to form the remainder of the three-dimensional metal casting mold; and
wherein the binder material includes at least one material selected from the group consisting of phenol resin, polyisocyanate, polyurethane, epoxy resin, furane resin, polyurethane polymer, phenolic polyurethane, phenol-formaldehyde furfuryl alcohol, urea-formaldehyde furfuryl alcohol, formaldehyde furfuryl alcohol, peroxide, polyphenol resin, resol ester, or mixtures thereof, and
wherein the binder material is present at a concentration of less than 2 weight percent based on the total weight of the mold.
14. A method according to claim 13, wherein the sand is selected from quartz, zircon, olivine, magnetite, or combination thereof, and wherein the particles include at least 80 percent by volume particles with an average particle size ranging from about 30 \u03bcm to about 450 \u03bcm.
15. A method according to claim 13, wherein the activation agent includes one or more acids selected from the group consisting of sulfuric acid, sulfonic acid, phosphoric acid, hydrochloric acid and nitric acid.
16. A method according to claim 13, wherein the activation agent includes an amine.
17. A method according to claim 16 wherein, the activation agent includes an aliphatic amine.
18. A method according to claim 16 wherein the activation agent includes an aromatic amine.
19. A method according to claim 15, wherein the sand includes reclaimed sand.
20. A method according to claim 16, wherein the sand includes reclaimed sand.
21. A method according to claim 15, wherein at least one period of at least 2 hours elapses between steps (a) and (b).
22. A method for making a mold for a metal casting comprising the steps of:
a. coating a plurality of individual uncoated sand particles, having an uncoated diameter, with an acidic activation agent for forming a plurality of individual coated sand particles having a resulting diameter of about 1.0 to about 2.5 times the uncoated diameter;
b. spreading a layer of the coated sand particles on a workpiece platform by dispensing coated sand particles through an opening of a moveable hopper;
c. forming a smooth layer having a thickness of from about 0.15 to about 0.30 mm;
d. selectively contacting the resulting smooth layer with a furane resin binder material, a binder material, or both by dispensing the resin, in droplets of a density of 100 to 600 dots per inch and no earlier than when the furane resin or binder material first contacts the activation agent, through a piezo bending drop-on-demand print head, the binder being dispensed in an amount of about 2 parts binder to 1 part activation agent;
e. curing the binder at ambient room temperature for causing the binder to crosslink and covalently bond the resin to form a matrix in which the sand particles are dispensed;
f. repeating at least steps (b)-(e) until a metal casting mold is completed
wherein the binder material is present at a concentration of less than 2 weight percent based on the total weight of the mold.
23. A method according to claim 22 further comprising a step of reclaiming sand that is not contacted with the binder.
24. A method according to claim 23, wherein the sand includes reclaimed sand that is free of binder material.
25. A method according to claim 23, wherein the acidic activation agent includes one or more acids selected from the group consisting of sulfuric acid, sulfonic acid, phosphoric acid, hydrochloric acid, and nitric acid.
26. The method of claim 25, wherein the acid includes sulphuric acid.
27. The method of claim 25, wherein the acid includes sulfonic acid.
28. The method of claim 25, wherein the coating step includes contacting the sand particles with a polyol.
29. The method of claim 25, wherein the binder material comprises the furane resin binder material.
30. A method for manufacturing a three-dimensional metal casting mold, comprising the following successive steps:
a) providing a plurality of individual particulates comprising sand, wherein at least a portion of a surface of the individual particulates is pre-coated with an activation agent;
b) contacting a pre-selected portion of the particulates having the activation agent present upon the particulates with a binder material that is activatable by the activation agent;
and
c) at least partially hardening the binder material, for forming a layer of the three-dimensional metal casting mold;
wherein the binder material is present at a concentration of less than 2 weight percent based on the total weight of the mold.
31. A method according to claim 13, wherein the ratio of binder to activation by weight is about 1:4 to about 4:1.
32. A method according to claim 13, further including a reinforcement.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A flue heat transfer system for transferring heat from a furnace heat source in a flue gas pipe, said flue heat transfer system comprising:
a heat exchanger integrated in a flue gas pipe and possessing a liquid media chamber, impinged by an all-enveloping flue gas flow, said heat exchanger comprising an inner and outer heat exchanger regions, said inner and outer heat exchanger regions having a configuration to be impinged by said flue gas flow;
pivotal guide plates arranged spatially one behind the other along a longitudinal axis in said inner heat exchanger region; and
a connecting rod mechanically connected between said guide plates;
wherein said guide plates having a configuration that deflects said flue gas flow from said inner heat exchanger region into said outer heat exchanger region up to an exterior wall of said flue gas pipe, such that, at low flue gas temperatures, said guide plates do not cause any deflections of said flue gas flow through said heat exchanger regions and that, with increasing flue gas temperatures, deflections of said flue gas flow as well as a resulting flue gas flow turbulence increases with degreasing angles of said guide plates.
2. The flue heat transfer system according to claim 1, wherein each of said guide plates are pivotable so as to adjust an angle of each of said guide plates to said flue gas flow about a pivoting axis of said guide plates.
3. The flue heat transfer system according to claim 2, wherein at least one of said guide plates being fitted with at least one drive means selected from the group consisting of a servo drive means, an electrically-driven servo drive means, and a rotary drive means, said drive means having a configuration for adjusting said angle of said guide plates.
4. The flue heat transfer system according to claim 1, wherein said guide plates each further comprising a hinge mechanically connected to said connecting rod, respectively.
5. The flue heat transfer system according to claim 4, wherein said guide plates are at least a first, second, third and fourth guide plate arranged spatially one behind the other in said longitudinal axis in said inner heat exchanger region.
6. The flue heat transfer system according to claim 5, wherein said connecting rod is a first connecting rod mechanically interconnecting said first and third guide plates, and a second connecting rod mechanically interconnecting said second and fourth guide plates.
7. The flue heat transfer system according to claim 6, wherein said first and second connecting rods are substantially parallel with said longitudinal axis during motion.
8. The flue heat transfer system according to claim 6, wherein said first connecting rod having a configuration to produce an equal, but synchronous direction of motion of said first and third guide plates, and said second connecting rod having a configuration to produce an equal, but synchronous direction of motion of said second and fourth guide plates that is opposite said first and third guide plates.
9. The flue heat transfer system according to claim 6 further comprising an intermediate connecting rod mechanically interconnecting said second and third guide plates in diagonally rotatable fashion, said intermediate connecting rod having a configuration to produce an opposite, but synchronous direction of motion of said second and third guide plates.
10. The flue heat transfer system according to claim 1 further comprising an upper support collar, a lower support collar, and a pair of support members in spaced relationship and connecting said upper and lower support collars, wherein said guide plates and said connecting rod are received in an interior of at least one of said upper and lower support collars, and said support members.
11. The flue heat transfer system according to claim 10, wherein said guide plates are pivotably connected to at least one of said upper and lower support collars, and said support members.
12. The flue heat transfer system according to claim 1 further comprising at least one pre-adjustment spring placed about at least one guide plate pivot pin at least one of said guide plates, said pre-adjustment spring having a configuration to provide a rotational biasing force against the at least one of said guide plates.
13. The flue heat transfer system according to claim 12, wherein said pre-adjustment spring includes at least one end received in at least one pre-adjustment hole defined in at least one of said support members.
14. The flue heat transfer system according to claim 13, wherein said pre-adjustment hole is a plurality of pre-adjustment holes oriented in a radially configuration at different angles from said longitudinal axis.
15. The flue heat transfer system according to claim 13 further comprising a limiter received through wherein at least one limiter hole defined in at least one of said support members, said limiter having a configuration to contact at least one of said guide plates to prevent rotation of the least one of said guide plates.
16. The flue heat transfer system according to claim 1, wherein said guide plates each feature textured surfaces having a configuration to increase friction of said flue gas flow.
17. The flue heat transfer system according to claim 1 further comprising an electrically-driven fan having a configuration for regulating said flue gas flow in one of said flue gas discharge pipe, in a fireplace, in a chimney, at an end of a chimney, adjacent to said flue gas discharge pipe, and in a region of a fresh air supply of a furnace.
18. The flue heat transfer system according to claim 2, wherein said heat exchanger further comprising at least one conduit having a configuration to form a hollow body, with said inner heat exchanger region having a configuration to receive said guide plates and said connecting rod.
19. The flue heat transfer system according to claim 18, wherein said conduit is selected from the group consisting of:
a plurality of tubular rods, which together, by using a plurality of 180\xb0 pipe bends, form a plurality of pipe loops that are interconnected in series to form said hollow body having a circular shape, said pipe loops having a configuration to be impinged by said enveloping flue gas flow, and wherein said heat exchanger is provided with a connecting sleeve for a return flow at a starting point and a connecting sleeve for a feed flow at an end point;
a plurality of tubular rods, which, by means of two hollow rings, respectively provided at a beginning point and an end point of said tubular rods, are interconnected by welding, such that said hollow body having a circular shape is obtained, a first of said hollow ring being provided with a connecting sleeve for a return flow and a second of said hollow rings being provided with a connecting sleeve for a feed flow, said hollow rings having a configuration to be impinged by said enveloping flue gas flow;
a coiled pipe, which consists of a circularly curved pipe and each individual loop of which includes an air gap for impinging said heat carrier medium by an all-enveloping said flue gas flow; and
a liquid jacket, arranged between two jacketing pipes associated with said flue gas pipe, said heat carrier medium flows through said jacketing pipes, and wherein an air gap is defined between an outer jacketing pipe surface and an inner surface of said flue gas pipe for a portion of said flue gas flow to flow through.
20. A method of using a heat transfer system for transferring heat from a furnace heat source, said method comprising the steps of:
a) setting a flue gas flow while a furnace is heating up by one of manual operation, and automatic control operation;
b) setting a rotational speed of ventilation and an angular position of guide plates in a heat exchanger integrated in a flue gas pipe of said furnace;
c) enveloping a liquid media chamber, said guide plates and inner and outer heat exchanger regions of said heat exchanger with said flue gas flow, said pivotal guide plates being arranged spatially one behind the other in a longitudinal axis in said inner heat exchanger region; and
d) pivoting at least a first of said guide plates that is mechanically connected to at least another of said guide plates;
wherein said guide plates having a configuration to deflect said flue gas flow from said inner heat exchanger region into said outer heat exchanger region up to an exterior wall of said flue gas pipe, such that, at low flue gas temperatures, said guide plates do not cause any deflections of said flue gas flow through said inner and outer heat exchanger regions and that, with increasing flue gas temperatures, deflections of said flue gas flow as well as a resulting flue gas flow turbulence increases with decreasing angles of said guide plates.