Patent Application
20250044031
This invention relates to a structure hanger for a refractory brick and/or refractory bricks, such as in a high temperature furnace.
Different types of conventional high-temperature furnace constructions are often used in a wide variety of industries, for example, the production of glass, steel, oil and/or petrochemicals. Some conventional high-temperature furnaces are built or constructed from refractory bricks or firebricks and/or tiles and are often supported by metal structural frameworks. Many conventional furnace constructions include installations or constructions in monolithic and suspended or tieback refractory structures.
Some conventional high-temperature furnaces include interior structures of heat-resistant refractory firebricks and/or tiles. Such interior structures are often relatively heavy and require substantial support structures, such as a roof structure or a sidewall structure, and a heavy or substantial support frame which can be constructed from structural steel. Many conventional support frames include relatively large 1-beams and/or wide flange beams with smaller I-beams, for example 3-inch sized 1-beams, which can act as hanger beams, for example, positioned at right angles to the beams of the support frame.
U.S. Pat. No. 3,958,519 (the 519 Patent) discloses conventional technology, the entire disclosure of which is completely incorporated merely by reference into this specification. The 519 Patent shows a conventional refractory brick anchoring system having a support frame I-beam and a flange over which hanger beam clips engage.
One conventional method of hanging the refractory bricks to the hanger beams overcomes some of the above disadvantages with a bent rod type or ice tong shaped refractory hanger which is made as two separate pieces. One conventional rod type refractory hanger extends under the hanger flange on one side of the refractory brick and hooks on the opposite hanger beam flange. The other hanger extends under the hanger flange on the other side of the refractory brick and hooks on the other hanger beam flange and causes a tightening action as gravity weight is applied by the refractory bricks. While these conventional hangers prevent the refractory brick from sliding out of the hanger, they also cause the refractory bricks to break or fracture because of an immovability of the hanger bricks and the forces which result from expansion upon heating the furnace.
The 519 Patent teaches an angle refractory hanger 40 having two interlocked opposing U-shaped portions 42 and 45. Each U-shaped portion 42 has opposing flanges 41 and 47 extending inwardly from the end of each U-shaped leg and side 43 of U-shaped portion 42 connects the legs opposite from the opening between flanges 41 and 47. Flanges 46 and 48 engage hanger flanges 16 of refractory brick 13. The 519 Patent further explains the value of this design in relation to the conventional system shown in
The 519 Patent teaches two known U-shaped halves made from sheets of stainless steel that are welded together to maintain a conventional perpendicular orientation. The 519 Patent teaches refractory hangers that can engage with, for example, AISC S3 3″ high steel beams, and there are also various known refractory hanger designs that engage with, for example, AISC S4 and S5 4″ and 5″ high steel beams.
These conventional systems have some commercial and technical deficiencies. For example, some users do not want the relatively thin metal construction of the conventional refractory hangers because they are not robust enough and some users desire a heavier duty version of the conventional refractory hangers. Also, the higher temperature field applications require higher grades of stainless steel, such as type 309 or 310 instead of the type 304. Further, the two U-shaped halves can separate from each other during shipping, handling and/or installation.
In order to address some of the deficiencies, it is possible to upgrade the material to type 309/310 stainless steel or a thicker type 304 stainless steel but this often results in a relatively high cost that is not cost effective for many of the field applications. It is possible to manufacture this by casting it in heat-resistant metal alloys, and in some field applications, the casting can withstand constant service high temperatures. Different foundries provide their own type of heat-resistant metal alloys where there is often no related industry standard or classification.
According to some embodiments of this invention, increased strength and lower internal stress levels are desirable. A casting according to the 519 Patent used the two U-shaped halves, merged them at a central plane, and increased a material thickness. Analysis of the casting according to the 519 Patent shows certain internal stresses at high temperatures. If higher loads or lower strength alloys are used with the casting according to the 519 Patent, failures could result.
In view of the limitations of a casting according to the 519 Patent, this invention includes several different embodiments based on using a steel beam and refractory contact flanges as fixed surfaces and arranging alternate structural paths between these two surfaces. Analysis according to castings of this invention show lower internal stresses which are acceptable when using certain other cast alloy types.
Castings according to different embodiments of this invention have some advantages over conventional castings. For example, a casting according to this invention reduces the maximum internal stresses significantly, for example, by eliminating the sharp transitions at the central plane in the casting according to the 519 Patent. According to different embodiments of this invention, this arrangement also reduces stress and allows the casting to be made from alternate materials, which cost less per pound. According to some embodiments of this invention, the casting specifications, for example, reduce the casting weight by almost 10% compared to a casting according to the 519 Patent. According to different embodiments of this invention, the casting requires a relatively large amount of casting part grinding after the casting process, for example, due to the complex nature of the tooling required to make the differently shaped casting. In other embodiments of this invention, the part grinding can be eliminated on the casting part primarily due to a simpler flow path through the foundry tooling.
Some features and embodiments of this invention are apparent to those skilled in the art and are described in the following description taken in view of the drawings, wherein:
This invention relates to a suspended roof construction and the same or similar roof construction can be used in a monolithic refractory construction and/or a tie-back wall construction. This invention also relates to refractory structures other than normal furnaces, for example, soaking pit covers, reheat furnaces, pelletizing furnaces, refractory lined reactors and/or refractory lined catalytic cracking units. The features of this invention can be used in any type of refractory brick structure.
U.S. Pat. No. 3,958,519 (the 519 Patent) teaches a high temperature furnace construction and hangers and all of its teachings and its entire disclosure is completely incorporated, by reference alone, into this specification. The 519 Patent shows one conventional refractory brick anchoring system having a support frame I-beam and a flange over which hanger beam clips engage. The conventional hanger beam clips slide over a flange from an end of the beam and each hanger beam clip engages one side of the flange of the hanger beam. The conventional hanger beam clips are secured by a bolt and an opposite hanger beam flange engages one slot of a refractory hanger with the refractory hanger slid over the flange from the end of the hanger beam. The opposite slot of the refractory hanger engages the hanger flanges of the refractory brick.
The 519 Patent teaches combinations of components or elements positioned so that the hanger flanges of the refractory brick are parallel to the hanger beam flanges. With the frequent requirement to slide the refractory hanger over the end of the hanger beam to engage it on the hanger beam flange, installation is difficult in such conventional systems because the refractory brick can slide out of the refractory hanger on a sloping roof or can vibrate out on a flat roof. Also, the cast form of the refractory hanger is relatively expensive and requires special heat-resistant materials that are not practical to use when cast or machined shapes are necessary.
In some embodiments according to this invention, structure hanger 40′ as shown in
In some embodiments according to this invention, structure hanger 40′ replaces or can be used in lieu of refractory hanger 40 as shown in
In some embodiments of this invention, column arm 20 of structure hanger 40′ has two upper flanges 60 and two lower flanges 70. According to some embodiments of this invention, upper flanges 60 are parallel and/or generally parallel to each other and/or lower flanges 70 are parallel and/or generally parallel to each other. In some embodiments of this invention, upper flanges 60 are generally parallel to each other and lower flanges 70 are generally parallel to each other, and having upper flanges 60 generally perpendicular to lower flanges 70 allows structure hanger 40′ of this invention to replace and/or be used in lieu of refractory hanger 40 as shown in
In some embodiments of this invention, structure hanger 40′ has two upper flanges 60, two lower flanges 70 and four column arms 50 each extending between upper flange 60 and lower flange 70. According to some embodiments of this invention, lower flange 70 is attachable to refractory brick flange 16, as shown in
In some embodiments of this invention, such as shown in
According to some embodiments of this invention, upper flange 60 is releasably attachable to a support structure, such as support beam 12 of the 519 Patent, for example, in a high temperature furnace structure.
In some embodiments of this invention, such as shown in
According to some embodiments of this invention, a method for using structure hanger 40′ in a high temperature furnace, includes forming a plurality of curved column arms 50, forming two upper flanges 60, and forming two lower flanges 70 so that each curved column arm 50 extends between a corresponding pair of upper flange 60 and lower flange 70. In some methods according to this invention, lower flanges 70 are removably attached, secured and/or otherwise connected to refractory brick flange 16 and/or another part of refractory brick 13.
In some embodiments according to this invention, structure hanger 40′ is manufactured and/or fabricated from structural steel and/or formed by other known metal forming techniques.
While in the specification this invention has been described in relation to certain embodiments thereof, and many details have been set forth for purpose of illustration, it will be apparent to those skilled in the art that this invention is susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of this invention.
