Patent Application
20240044433
Not applicable.
Not applicable.
The present disclosure generally relates to a bulkhead fitting. More specifically, the disclosure relates to a fitting that can be installed on a tank or vessel when access to the interior of the tank or vessel is not available.
Bulkhead fittings are standard equipment in many industrial and commercial settings. A bulkhead fitting is a watertight connection (NPT/BPT threads, quick disconnect, Sharkbite® fitting, etc.) that is fitted to any thin-walled vessel. A standard bulkhead fitting consists of a threaded male coupling inserted into a hole in the vessel, a sealing compression washer, and female nut on the inside of the vessel. The female nut is tightened on the male coupling to compress the washer and create a liquid-tight seal, even at high pressure. With the traditional fitting configured with the nut inside the tank, threading anything into the bulkhead fitting will tighten the fitting itself. Traditional bulkhead fittings are easy to install prior to the tank or vessel being placed into service, when the interior of the tank or vessel is dry and accessible. However, there are situations where it is desirable to install a bulkhead fitting on an existing vessel, which may be filled with a liquid. In addition, the inside of the vessel may be difficult or impossible to access, creating a ‘blind’ situation where the internal nut can not be installed.
To address the problem of installing ‘blind’ fittings, others have used weld-on fittings, weldless tank bushings, RV bulkhead tank fittings, and similar fittings. The weld-on fitting is a steel plumbing fitting that is welded to the outside of the vessel. This creates an excellent pressure-rated seal, but requires that the vessel be made of steel and the fitting is difficult to install and remove. A weldless tank bushing does not require welding equipment and is removable. The downside to this type of bushing is that it requires an oversized hole for installation, the gap of which is covered by a large washer. Additionally, during install and use, there is no way to keep the body of the bushing from rotating in the hole, meaning it is impossible to fully tighten either the outer nut or the plumbing line you are attempting to attach. As a result, this fitting is not usable for installation below the liquid surface level or in a pressurized situation. An RV bulkhead fitting uses a rubber or PVC grommet and threaded nut arrangement for easy installation but does not have a mechanical flange to prevent dislodgement from the tank. Thus, RV fittings are not designed for pressurized vessels and can suffer from failure if the grommet deteriorates. Therefore, it would be advantageous to develop a fitting that makes installation easier and permits retrofitting in pressurized tanks and vessels.
According to embodiments of the present disclosure is a blind bulkhead fitting that is adapted to permit one-sided installation (i.e. exterior access only) and provides a mechanical, non-friction hold on the tank. In one example embodiment, the bulkhead fitting comprises an inner fitting, an inner nut, and an outer fitting, which may include an o-ring seal. The inner fitting is pressed through a hole in the tank from the external side of the tank and secured with the inner nut. The outer nut threads onto the inner fitting, completing the water-tight connection. The outer nut may include a standard connection, such as NPT threads.
According to embodiments of the disclosure is a blind bulkhead fitting 100 comprising an inner fitting 101, an outer fitting 102, and an inner nut 103. The fitting may also include an o-ring 104 and a curved washer. As shown in
As shown in
Once the inner fitting 101 is pressed into the installation hole of the tank, the inner nut 103 threads into the inner fitting 101 to prevent compression of the inner fitting 101. The inner nut 103 may include an internal hex slot to allow tightening with a hex wrench. Similar tightening methods can also be used in other embodiments.
While
The outer fitting 102 comprises a sealing surface for engaging the outside of the tank or vessel. Internal threads engage the external threads of the inner fitting 101. The outer fitting may also include internal NPT threads or other connection mechanisms 113 for a pipe, tubing, or a similar supply/discharge line as shown in
To install the blind bulkhead fitting 100, first the inner fitting 101 is inserted into a hole in the tank. In one example embodiment, the inner fitting 101 is compressed prior to installation. In another example embodiment, the flange 110 includes a slight taper on the leading edge which will force the inner fitting 101 to compress as it is driven into the hole. Next, the inner nut 103 is threaded into the inner fitting 101, locking the flange 110 against the interior of the tank wall. Next, the optional o-ring 104 and/or curved washer are installed before threading the outer fitting 102 onto the inner fitting 101. Because of the orientation of the threads, tightening a supply line onto the outer fitting 102 will also tighten the outer fitting 102 onto the inner fitting 101.
When used in this specification and claims, the terms “comprises” and “comprising” and variations thereof mean that the specified features, steps, or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.
The invention may also broadly consist in the parts, elements, steps, examples and/or features referred to or indicated in the specification individually or collectively in any and all combinations of two or more said parts, elements, steps, examples and/or features. In particular, one or more features in any of the embodiments described herein may be combined with one or more features from any other embodiment(s) described herein.
Protection may be sought for any features disclosed in any one or more published documents referenced herein in combination with the present disclosure. Although certain example embodiments of the invention have been described, the scope of the appended claims is not intended to be limited solely to these embodiments. The claims are to be construed literally, purposively, and/or to encompass equivalents.
