Patent Application
20060087121
The present invention relates in general to an apparatus for installation on a pipe and in particular to an apparatus employed in the restraint of connected pipes to prevent the separation thereof.
A conventional connection that joins two adjacent pipes in a fluid-transporting pipeline system is sometimes subjected to internal hydrostatic pressure and/or other external and/or internal forces that tend to deflect or separate one pipe from the other. To combat this separation, a pipe-restraining assembly may be installed across the connection between the two pipes to penetratingly engage and maintain the pipes in a fixed position relative to each other.
However, a typical pipe-restraining assembly may not be suitable for all types of pipe materials. That is, the ability of the pipe-restraining assembly to penetratingly engage and restrain a pipe is dependent upon the pipe surface having a material hardness that is relatively low. Thus, the pipe-restraining assembly may not be able to prevent the axial separation of pipes having relatively high material hardness levels.
Therefore, what is needed is an apparatus for installation on a pipe and an accompanying method that, among other things, may be used to overcome the above-described problem.
Referring to
The assembly 10 includes two spaced pairs of arcuate members 16a and 16b, and 18a and 18b. Each pair of arcuate members 16a and 16b, and 18a and 18b, forms a ring that envelops portions of and clamps around the pipes 12 and 14, respectively.
As more clearly shown in
The arcuate member 16a defines a curved surface 30, with the opposing ends of the curved surface 30 terminating at the chamfers 22a and 22b. A plurality of protrusions or ridges 32a, 32b, 32c and 32d extend radially inward from the curved surface 30 so that the distal ends of the ridges 32a-32d are radially offset from the curved surface 30. The ridges 32a-32d also extend along the length of the curved surface 30. The curved surface 30, and the ridges 32a-32d, include opposing portions 34a and 34b which are substantially defined by and substantially extend from the ears 20a and 20b, and to the lugs 28a and 28b, respectively. At least some of the material in each of the portions 34a and 34b has a material hardness that is higher than the remainder of the arcuate member 16a, including the remainder of the curved surface 30 and the ridges 32a-32d. It is understood that the portions 34a and 34b may be caused to have a material hardness that is higher than the remainder of the arcuate member 16a by performing a material-hardening process of such portion such as, for example, a conventional heat treating process.
The arcuate members 16b, 18a and 18b are identical to the arcuate member 16a and thus will not be described in detail. Parts of the arcuate members 16b, 18a and 18b corresponding to identical parts of the arcuate member 16a are given the same reference numerals.
Referring to
Likewise, bolts 40a and 40b extend through the vertically-aligned bores 26a and 26b of the arcuate members 18a and 18b, respectively, and are threadably engaged with nuts 42a and 42b, respectively. These threaded engagements connect the arcuate members 18a and 18b and clamp the members around the pipe 14. The surface 24a of each arcuate member 18a and 18b almost contacts or contacts the corresponding surface 24a of the other arcuate member, and the surface 24b of each arcuate member almost contacts or contacts the corresponding surface 24b of the other arcuate member. The ridges 32a-32d of each arcuate member 18a and 18b penetratingly engage the pipe 14.
A tie rod 42 extends through each aligned bore 28a′ of the arcuate members 16b and 18b so that the tie rod is in a parallel relation with the coaxial longitudinal axes of the pipes 12 and 14. Nuts 44a and 44b are threadably engaged with the distal and proximal ends of the tie rod 42, respectively, thereby connecting the arcuate members 16a and 16b with the arcuate members 18a and 18b. In an identical manner, a tie rod 46 extends through each aligned bore 28b′ of the arcuate members 16b and 18b, and nuts 48a and 48b are threadably engaged with the distal and proximal ends of the tie rod, respectively. Similarly, tie rods 50 and 52 extend through each aligned bore 28a′ and 28b′, respectively, of the arcuate members 16a and 18a (tie rod 52 shown in
In operation, with continuing reference to
However, pipe-restraining assembly 10 restrains or prevents the pipe 12 from appreciably moving axially relative to, or separating from, the pipe 14, and vice versa. The penetrating engagement of the ridges 32a-32d of the arcuate members 16a and 16b into the pipe 12 prevents the arcuate members from moving axially relative to the pipe 12. Likewise, the penetrating engagement of the ridges 32a-32d of the arcuate members 18a and 18b into the pipe 14 prevents the arcuate members from moving axially relative to the pipe 14. Further, the clamping forces generated by the threaded engagements of the tie rods 42, 46, 50 and 52 with the nuts 44a and 44b, 48a and 48b, 54a and 54b, and 56a and 56b, respectively, and applied to the corresponding lugs 28a and 28b, prevents the arcuate members 16a and 16b from moving axially relative to the arcuate members 18a and 18b, and vice versa. Since the arcuate members 16a and 16b, and 18a and 18b, are prevented from moving relative to the pipes 12 and 14, respectively, and from moving relative to each other, the pipes 12 and 14 are therefore prevented from appreciably moving relative to and/or axially separating from one another.
The sections of the ridges 32a-32d located in the portions 34a and 34b of the arcuate members 16a and 16b penetratingly engage the pipe 12 to a greater degree than the sections of the ridges 32a-32d that are located outside of the portions 34a and 34b. The aforementioned heat treatment of the portions 34a and 34b and the corresponding increase in hardness promotes the increased penetration of the ridges 32a-32d into the pipe 12 at the portions. Also, the inwardly-directed radial forces exerted on the pipe 12 by the arcuate members 16a and 16b are relatively higher at the portions 34a and 34b due to the portions' proximity to the clamping forces generated by the threaded engagement of the bolts 36a and 36b with the nuts 38a and 38b, respectively, and applied to the ears 20a and 20b, respectively, thereby further promoting the increased penetration of the ridges 32a-32d into the pipe at the portions.
In a like manner, the sections of the ridges 32a-32d located in the portions 34a and 34b of the arcuate members 18a and 18b penetratingly engage the pipe 14 to a greater degree than the sections of the ridges 32a-32d that are located outside of the portions 34a and 34b. Thus, the increased penetration of the ridges 32a-32d at the portions 34a and 34b further prevents the arcuate members 16a and 16b, and 18a and 18b, from moving relative to the pipes 12 and 14, respectively, thereby further inhibiting any axial separation of the pipes.
Referring to
In a like manner, inserts identical to the insert 62 are disposed in recesses formed in the opposing end of the arcuate member 16a, and in the opposing ends of the arcuate members 16b, 18a and 18b. It is understood that, with the exception of the foregoing, the pipe-restraining assembly 58 is identical to the pipe-restraining assembly 10 and therefore will not be further described.
The operation of the embodiment of
It is understood that variations may be made in the foregoing without departing from the scope of the disclosure. For example, only one pair of arcuate members 16a and 16b, or 18a and 18b, may include the ridges 32a-32d.
Further, instead of connecting the pair of arcuate members 16a and 16b to another pair of identical arcuate members such as the arcuate members 18a and 18b, the pair of arcuate members 16a and 16b could be connected to the restrained sleeve pipe coupling and/or one or more of the corresponding end rings disclosed in co-pending patent application Ser. No. 10/170,477, the disclosure of which is incorporated by reference.
Still further, the pair of arcuate members 16a and 16b could be employed in conjunction with a conventional flanged connection between a pipe having a flange and a pipe having a plain end. The arcuate members 16a and 16b could be clamped together around the pipe having the plain end in a manner described above, and the tie rods 42, 46, 50 and 52 could extend from the arcuate members 16a and 16b and through bores formed in the flange. The nuts 44b, 48b, 54b and 56b could then be threadably engaged with the tie rods 42, 46, 50 and 52, respectively, to apply clamping forces to the flange and promote a flanged connection that is more resistive to any forces tending to separate the pipes. It is understood that the flanged connection may be between straight pipe sections, curved pipe sections, etc. or any combination thereof.
In view of the foregoing, it is understood that the pair of arcuate members 16a and 16b, or 18a and 18b, may be clamped around any pipe in any type of application where it is desired to form a ring around the pipe and maintain the as-installed position of the arcuate members relative to the pipe, notwithstanding the subsequent subjection of the installed arcuate members, or ring, to various static and/or dynamic loads in various directions.
Additional variations include the following:
Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many other modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures.
