Patent Application
20100213707
The present disclosure relates to various fluid flow devices, and more specifically to the connection of threaded fittings to various fluid flow devices.
This section provides background information related to the present disclosure which is not necessarily prior art.
Many fluid flow apparatus or valves are adapted to be connected to small diameter fittings or pipelines via threaded joints, for communication of gas, water or other fluids therethrough. Because pipe joints or threaded fittings typically have tapered pipe threads, such threaded fittings can easily become cross-threaded if the threaded opening in the fluid flow device and the threaded fitting are not properly aligned with each other.
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
Various embodiments of a fluid flow apparatus are disclosed that are configured to receive a threaded fitting in a manner such that the mating threaded fitting aligns with an internally threaded hole in the apparatus so that cross-threading is avoided. In one embodiment, a fluid flow apparatus includes a housing or body having an outer surface, and an internally threaded hole in the outer surface of the body. The internally threaded hole may have a number of start threads with an associated thread lead distance. The fluid flow apparatus further includes at least two slots in the outer surface of the body, where the slots extend to and intersect the internally threaded hole in the outer surface of the body. The at least two slots have a depth from the outer surface that is more than ½ the thread lead distance but less than 1½ times the thread lead distance, such that for each start thread only a first coil (or wrap, turn, revolution, etc.) of the start thread has a full threadform cross-section that is exposed by the slots. Accordingly, the depth of the at least two slots create only one fully exposed threadform that provides a lead-in notch configured to enable a mating threaded fitting to align with the internally threaded hole, to more effectively avoid cross-threading.
Further areas of applicability will become apparent from the description of the various embodiments provided herein. The description and specific examples in this summary are intended for purposes of illustration only, and are not intended to limit the scope of the present disclosure to the specific embodiments described.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
Example embodiments will now be described more fully with reference to the accompanying drawings.
In the various embodiments of the present disclosure, a fluid flow apparatus is provided that is configured to be connected to a threaded fitting for communication of a fluid therethrough. According to one aspect of the present disclosure, the various embodiments of a fluid flow apparatus include an internally threaded hole configured to be connected to a threaded fitting in a manner such that the mating threaded fitting aligns with the internally threaded hole so that cross-threading is avoided. One embodiment of a fluid flow apparatus configured to receive a threaded fitting is shown as 100 in
The internally threaded hole 106 may have a number of start threads 110, 112, which have an associated thread lead distance ‘L’ and pitch ‘P’. The pitch ‘P’ is the distance from the crest of one thread to the next adjacent thread. The thread lead distance ‘L’ is the distance along the axis X of the internally threaded hole 106 that covers one complete coil or rotation of a start thread 110, which corresponds to one rotation of a threaded fitting (not shown) that may be received within the internally threaded hole 106. The internally threaded hole 106 may have multiple start threads or a single start thread. A single start thread means only one thread is helically coiled around the cylinder of the internally threaded hole 106, where each full rotation (360°) of a mating threaded fitting causes the fitting to advance axially the pitch width of one thread within the internally threaded hole 106. A single start thread also requires a full turn of a threaded fitting within the internally threaded hole 106 before the threads of the fitting completely engage the start thread in the internally threaded hole 106. A double start thread means that there are two start threads in parallel that are helically coiled around the cylinder of the internally threaded hole 106, where the distance between the first start thread and second start thread is the pitch, and the thread lead distance ‘L’ along the axis X that corresponds to one complete coil or rotation of one start thread is twice the pitch. Thus, each full rotation (360°) of a mating threaded fitting relative to a double start thread would cause the fitting to advance axially the pitch width of two threads (i.e., the thread lead distance). A double start thread also requires only a half-turn of a threaded fitting within the internally threaded hole 106 before the threads of the fitting completely engage the start threads of the internally threaded hole 106.
Threaded fittings, especially fittings having tapered ‘NPT’ pipe threads, can easily become misaligned with respect to a standard internally threaded hole in a fluid flow device, and can have a tendency to cross-thread. Cross-threading can lead to a compromised fit, and leakage of fluid at the fitting connection. To address this concern, the various embodiments comprise at least two slots 120, 122 in the outer surface 104 of the body 102, each of which extend to and intersect the internally threaded hole 106 in the outer surface 104. The at least two slots 120, 122 have a depth less than 1½ times the thread lead distance ‘L’ such that for each start thread 110, 112 only a first coil, wrap, turn or revolution of the start thread has a full threadform cross-section cut-away or exposed by the at least two slots 120, 122, which provides a lead-in notch 124, 126 configured to enable a mating threaded fitting to align with the internally threaded hole 106, as explained in the following description of the embodiments.
Referring to
Additionally, the at least two slots 120, 122 extend a minimum length to the internally threaded hole 106, such that the length ‘l’ of the at least two slots 120, 122 is substantially insufficient to permit a tool to apply a rotational torque via the at least two slots 120, 122. Preferably, the at least two slots 120, 122 extend a length ‘l’ that is less than 1½ times the thread depth. The at least two slots may have a width ‘W’ that is a ratio of the thread lead distance ‘L’, where the ratio of the width ‘W’ to the thread lead distance ‘L’ is between 1:1 and 1:2 (the width ‘W’ is more than the thread lead distance ‘L’ but less than twice the thread lead distance ‘L’). The at least two slots 120, 122 may be disposed on diametrically opposite sides of the internally threaded hole 106 as shown in
Referring to
In the second embodiment, the at least two slots 220, 222 extend a minimum length to the internally threaded hole 206, such that the length ‘l’ of the at least two slots 220, 222 is substantially insufficient to permit a tool to apply a rotational torque via the at least two slots 220, 222. Preferably, the at least two slots 220, 222 that extend to the internally threaded hole 206 have a length ‘l’ less than 1½ times the thread depth. The at least two slots 220, 222 may have a width ‘W’ that is a ratio of the thread lead distance ‘L’, where the ratio of the width ‘W’ to the thread lead distance ‘L’ is between 1:1 and 1:2. The at least two slots 220, 222 may be disposed on diametrically opposite sides of the internally threaded hole 206 as shown in
Referring to
In the third embodiment, the at least three slots 320, 322, 324 extend a minimum length to the internally threaded hole 306, such that the length ‘l’ of the at least three slots 320, 322, 324 is substantially insufficient to permit a tool to apply a rotational torque via the at least three slots 320, 322, 324. Preferably, the at least three slots 320, 322, 324 that extend to the internally threaded hole 306 have a length ‘l’ less than 1½ times the thread depth. The at least three slots 320, 322, 324 may have a width ‘W’ that is a ratio of the thread lead distance ‘L’, where the ratio of the width ‘W’ to the thread lead distance ‘L’ is between 1:1 and 1:2.
Referring to
In the fourth embodiment, the at least two slots 420, 422 extend a minimum length to the internally threaded hole 406, such that the length ‘l’ of the at least two slots 420, 422 is substantially insufficient to permit a tool to apply a rotational torque via the at least two slots 420, 422. Preferably, the at least two slots 420, 422 that extend to the internally threaded hole 406 have a length ‘l’ less than 1½ times the thread depth ‘D’. The at least two slots 420, 422 may have a width ‘W’ that is a ratio of the thread lead distance ‘L’, where the ratio of the width ‘W’ to the thread lead distance ‘L’ is between 1:1 and 1:2.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.
