Oven top section and method of construction
A top section for an oven formed with an outer support shell, an intermediate insulating layer and an inner refractory lining wherein the three layers are connected by a plurality of spaced members. The spaced members are preferably formed as stainless steel pegs welded to an inner surface of the outer support shell extending across the intermediate insulating layer and fixed to the inner refractory lining as a result of the cast refractory lining setting around the pegs. The pegs may be covered at least in part by a plastic tip or coating to provide a relative expansion capacity between the pegs and the refractory lining. The outer section is preferably formed from steel, may be any suitable shape and includes one or more apertures to form doorways, flues and access ports for accessory items such as char-grilles, lights, fire retardant systems and windows. The invention extends to an oven including a top section as disclosed. The invention also extends to a method of forming an oven comprising the steps of forming the outer housing, welding pegs to an inner surface of the outer housing, locating insulating material inside the outer housing, positioning a mold defining a cavity of the top section and pouring and setting a castable refractory lining of the oven. The method may further include the step of positioning plastic tips over the pegs.
1. A top section for an oven, the top section comprising:
an outer support shell,
an inner refractory lining,
an insulating layer intermediate the outer support shell and inner refractory lining and
connection means for connecting the outer support shell, inner refractory lining and intermediate insulating layer wherein the connection means comprise a plurality of spaced members fixed to the outer support shell, extending across the intermediate insulating layer and fixed to the inner refractory lining.
2. The top section of claim 1 wherein the spaced members are formed as pins.
3. The top section of claim 2 wherein the pins are stainless steel pegs.
4. The top section of claim 3 wherein at least some of the stainless steel pegs have an angled portion.
5. The top section of claim 2 wherein the pins are welded to the outer support shell.
6. The top section of claim 2 wherein the pins are fixed to the inner refractory lining as a result of the inner refractory lining being cast around a portion of the pins distal to the outer shell and being allowed to set.
7. The top section of claim 2 wherein the pins include a coating or cover applied to at least part of the outer surface of each pin including a distal region of the pin, wherein the coating or cover is adapted to provide an expansion space between the pin and the refractory lining to permit expansion of the pin relative to the refractory lining.
8. The top section of claim 7 wherein the coating or cover is formed from a plastics material.
9. The top section of claim 8 wherein the plastics material is a thermoplastic material.
10. The top section of claim 1 wherein the outer support shell is formed from steel.
11. The top section of claim 10 wherein the steel is 5 to 6 mm thick.
12. The top section of claim 1 wherein the outer support shell is substantially cylindrical.
13. The top section of claim 1 wherein the outer support shell is configured substantially as a box.
14. The top section of claim 1 wherein the inner lining is a refractory castable material.
15. The top section of claim 14 wherein the refractory castable material is a ceramic material.
16. The top section of claim 1 wherein the intermediate insulating layer comprises a fibrous insulating material.
17. The top section of claim 16 wherein the fibrous material is formed as a blanket.
18. The top section of claim 17 wherein the top section is formed from two or more subsections.
19. An oven comprising:
a top section comprising:
an outer support shell,
an inner refractory lining,
an insulating layer intermediate the outer support shell and inner refractory lining, and connectors for interconnecting the outer support shell, inner refractory lining and intermediate insulating layer wherein the connectors comprise a plurality of spaced members fixed to the outer support shelf, extending across the intermediate insulating layer and fixed to the inner refractory lining and a base engaged with the top section so as to together define an interior oven space.
20. The oven of claim 19 wherein the base comprises a metal support layer and a refractory layer abutting the metal support layer.
21. The oven of claim 20 wherein the refractory layer is formed of bricks.
22. The oven of claim 19 including at least one of an oven door, a viewing window, a char-grille, an internal light, a fire retardant system, one or more extra doors and a gas fire system.
23. The oven of claim 19 further comprising a support stand.
24. The oven of claim 19 further comprising a flue.
25. The oven of claim 19 further comprising an outer insulating layer positioned adjacent an outer surface of the outer support shell.
26. The oven of claim 19 further comprising a lintel extending from a door aperture.
27. A method of forming an oven top section, said method comprising the steps of:
forming an outer support shell;
fixing a plurality of inwardly directed pegs to the outer support shell;
locating an insulating material inside the outer support shell such that the pegs extend through the insulating material;
positioning a mould, the mould defining the shape of a cavity of the oven inside the outer support shell; and
casting a refractory material to form an inner lining of the oven top section, the refractory material positioned to set around a distal portion of the pegs.
28. The method of claim 27 wherein the outer support shell is formed with apertures for a door and a flue.
29. The method of claim 27 , further including the step of forming additional apertures for at least one of one or more extra doors, internal lights, a char-grille, a fire retardant system and a gas fired system.
30. The method of claim 27 further including the step of fixing the pegs to the outer shell by welding.
31. The method of claim 27 further including the step of locating a plastic layer or cover on a distal region of each of the pegs.
32. The method of claim 27 further including allowing the cast refractory material to set so as to form a base of the oven and fix the top section to the base.
33. The method of claim 27 further including the step of splitting the top section into two or more subsections each comprising an outer shell, an intermediate insulating layer and inner lining, transporting the subsections to an installation site and reforming the top section.