Patent Application
20090050078
Not Applicable
Not Applicable
1. Field of Invention
This invention pertains to boiler tubes.
More particularly, this invention pertains to boiler tubes which are periodically replaced and provide an improved structure for attachment and detachment from a boiler using standard tools.
2. Description of the Related Art
In the field of boilers, it is common to provide a supply manifold with a plurality of boiler tubes. Water is provided through the manifold to the boiler tubes to provide hot water or steam. Over time, the boiler tubes must be replaced because they receive the direct heat of the boiler and therefore deteriorate faster than the manifold. Accordingly, the boiler tubes have been releasably secured to the manifold for ease of replacement.
The standard connection method for releasably securing a boiler tube to a manifold is to define an aperture in the manifold, secure a tapered ferrule to the end of the boiler tube and then forcibly insert the ferrule into the aperture, as with a sledge hammer, for example. Unfortunately, there are several detrimental aspects of this attachment system.
One negative aspect of the system is that special tools are required to hold the boiler tube in position while it is struck to prevent damage to the tube and transfer the energy from the hammer to the tube. In addition, during transportation and installation of the boiler, it is common for a boiler tube to become dislodged from the manifold and thus require re-installation in the field. Again, special tools are required. Also, during field re-installation/replacement of boiler tubes, the Tube Keeper Bolts are prone to breakage. To replace the Tube Keeper Bolts requires certified welding, ASME Inspection, Hydro-Static Testing, and the required “R” Stamp denoting repair of the vessel.
Accordingly, it is desirable to provide a system for connecting a boiler tube to a manifold which requires only standard tools and which is not subject to disengagement during transport and installation.
According to one embodiment of the present invention, a boiler apparatus comprises a supply manifold which includes a first flange having a first aperture defined therein. A boiler tube, including a second flange having an aperture defined therein, is secured to the manifold. A releasable fastener maintains sealed engagement of the first flange with the second flange. The releasable fastener is removable for replacement using standard tools in contrast to the special tools required heretofore.
The above-mentioned features of the invention will become more clearly understood from the following detailed description of the invention read together with the drawings in which:
An apparatus for removably securing a boiler tube to a manifold is disclosed. Referring to the drawings in which numbered parts represent similar parts, a tubular boiler manifold 10 defines a plurality of first apertures 12. A first extension tube 14 extends radially outwardly from the first aperture 12 and defines a distal aperture 16. The first extension tube 14 is sealingly secured to the manifold 10, as by welding, for example.
A first flange 18 extends around the distal aperture 16. The first flange 18 is sealingly secured to the first extension tube 14 as by welding, for example. A plurality of first fastening apertures 20 are defined in the first flange 18. Each of the fastening apertures 20 is adapted to slidingly receive an elongated threaded bolt 22 having an expanded head 24 at one end and an opposing threaded distal end 26.
An elongated boiler tube 28 includes an attachment end section 30 which terminates in a shoulder 32 which extends circumferentially outwardly from the attachment end section 30 and defines a second aperture 34. A second flange 36 is slidingly mounted upon the boiler tube 28 and defines a plurality of second fastening apertures 38. Each of the second fastening apertures 38 is adapted to slidingly receive an elongated, threaded bolt 22 having an expanded head 24 at one end and an opposing threaded distal end 26. The pattern of first fastening apertures and the pattern of second fastening apertures are substantially identical so that when the bolts 22 are inserted through the first fastening apertures 20 and the second fastening apertures 38, the bolts 22 are aligned parallel to one another and generally perpendicular to the planes defined by the first flange 18 and the second flange 36.
A gasket 40 is located between the first flange 18 and the second flange 36. The gasket 40 defines a central aperture 42 substantially similar in size and shape to the first aperture 16 and the second aperture 34. The gasket 40 also defines a plurality of apertures 44 which are sized similarly to the fastening apertures 20 and 38 and arranged in a pattern similar to the apertures 20 and 38, whereby the bolts 22 extend through the apertures 44 when they extend through the apertures 20 and 38.
Each of the threaded bolts 22 is provided with a lock washer 46 and a threaded nut 48 adapted to threadably engage the bolt 22.
In operation, the gasket 40 is located between said first flange 18 and said second flange 36. The apertures 20 defined in the first flange 18 are aligned with the apertures 44 defined in the gasket 40 and with the apertures 38 defined in the second gasket. Simultaneously, the aperture 16 defined in the first flange 18 is aligned with the aperture 42 defined in the gasket and the aperture 34 defined in the boiler tube 28. A bolt 22 is inserted through each of the sets of aligned apertures 20, 44 and 38, a lock washer 46 is mounted upon the bolt 22 and a nut 48 is threadably mounted upon the bolt 22. Thereafter, the nuts 48 are tightened to sealingly engage the gasket 40 between the first flange 18 and the second flange 36. Simple wrenches may be used for the tightening of the nuts 48.
When a boiler tube 28 requires replacement, simple wrenches may be used to loosen the nuts 48 and the installation process is reversed to leave the manifold prepared for installation of a replacement boiler tube 28.
Those skilled in the art will recognize that various fasteners other than threaded bolts can be used without departing from the spirit and scope of the present invention. Also, the elimination of 1 or 2 or the fastening bolts, washers, and/or nuts should not be recognized as departing from the spirit of the invention.
While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept.
