US 3191632 A
Description (OCR text may contain errors)
June 29, 1965 A- KEIDING PIPE JACKET Filed Jan. 29, 1962 252.59. 6 LY JQf/OPEW IKE/D1186- United- States Patent ear,
, I 3,191,632 Patented June 29, 1965 partuership Filed Jan. 29, 1962, Ser. No. 169,450 6 Claims. (Cl. 138-451) This invention relates to a pipe'ja'cket.
The pipe jacket is primarily intended to insulate a pipe to which it is applied. In domestic usage it insulates hot water pipes to conserve the heat in the water and it insulates cold water pipes to preclude condensation of moisturc thereon. H
A major advantage of the pipe jacket herein disclosed is attributable to the ease with which it can be applied (or removed, if necessary). Split sleeves of insulating material have long been known but, in the case of all previous jackets, it has been necessary to employ some extraneous means of maintaining the split sleeve closed about the pipe to which it is applied.
The instant jacket is a split sleeve of molded insulating material such as ordinary paper pulp. In one sense each lateral section of the sleeve may be considered separately, since each has its own clamping engagement with the pipe. The pulp used may comprise felted wood fiber, usually mixed with sizing, and of the same type as that from which pulp fiowerpots and other pulp articles are molded. j
In considering as a whole a jacket embodying the present invention, there are two features which are of significance both independently and cooperatively. The two componenthalves of the jacket are unitar-ily connected across a 'slot extending longitudinally of the interior of the article. In effect, the connection has some of the characteristics of a hinge, as it permits the connected sections to be separated to receive the pipe. The hinged opening of the two sections for this purpose weakens the fiber in the zone beneath the slot. Instead of being a dis advantage, this is a very substantial advantage because it tends to destroy the natural resilience of the material and to facilitate complete closing thereof about the pipe, without any substantial tendency for the two halves to spring apart.
The second significant feature consists in the fact that the pipe receiving channel of each section is not semicircular in cross section but has an interior contour which is semi-elliptical. The major axis of the ellipse is transverse and is at least equal to the diameter of the pipe, and preferably somewhat exceeds the pipe diameter. The minor axis is in the plane intermediate the free margins and is somewhat less than the diameter of the pipe. Con: sequcntly, in closing the component sections of the article about the pipe, it is necessary that each of these sections must be sprung slightly against the inherent bias of the material and in a direction which displaces the free margin from the hinged connection between the sections. As aforesaid, there is considerable resilience in the felted pulp Moreover, the screen-formed inner surface has quite a high coefiicient of friction. Consequently, each section individually clamps itself upon half of the pipe and resists the re-opening of the sections. This securely anchors the jacket on the pipe to completely enclose the pipe securely without requiring any extraneous binder or other fastening means.
The clamping engagement of the two halves with the pipe is enhanced by the fact that the two sections individually are resilient where the fiber is unimpaired but the hinged connection of the two sections with each other has lost its resilience when the sections are sprung open to receive the pipe, the movement in such case being in excess of the elastic limit of the felted fiber.
The word pipe is used herein generically to include not merely pipe or tubing but also the fittings used therewith, examples being included in the drawings to show jackets molded to receive typical fittings and to retain themselves in clamped engagement on the fittings in the same manner as upon'a tube.
In the drawings:
FIG. 1 is a view in perspective of an article embodying the invention.
(FIG. -2 is a view in end elevation of the jacket shown in FIG. 1.
FIG. 3 is a view in end elevation showing the appearance of the jacket of BIG. 1 if the two sections thereof v are squeezed together without there being any intervening pipe: 9 *FIG. 4 is a view similar to FIG. 3 showing two sections closed upona pipe, the pipe being illustrated in sectron.
FIG. 5 is a view in perspective showing on an eniarged scale a jacket designed for a pipe tee.
FIG. 6 is a view similar to FIG. 5 showing an embodiment designed to fit upon a pipe elbow.
The embodiment shown in FIGS. 1 to 4 comprises semi-tubular jacket sections 8 and 10 unitarily joined at across a slot 14 extending longitudinally of the jacket from end to end of its inner surface directly opposite the free margins 16 and 18 of sections 8 and 10. While the manner in which the exterior of the jacket is. formed may be entirely immaterial, the device as shown has flat external surfaces 20 and 22 along the free margins 16 and'18.
Interiorly, each offthe sections 8 and 10 between the slot =14and the tree margin of the respective section constitu-tes a channel, fthecross sectional form of the channel being semi-elliptical. If the two sections are forced shut as shown in FIG. 3, the enclosed space will have the form of an ellipse in cross section, the transverse axis A being the major axis. The axis A should desirably equal or exceed the diameter of the pipe for which the jacket is designed. The axis B should be materially less than the diameter of the pipe for which the jacket is designed.
'It will be observed that if the jacket is forci'bly closed, as in FIG. 3, the surfaces 24 and 26 at the free margins of sections -8 and 10 will be outwardly convergent. Since no pipe" has been inserted, the elastic limit of the hinged connection at 12 between the sections has not been exceeded and the resilience thereof will tend to spring the sections apart toward the position of FIG. 2.-
However, if the sections are opened up to receive a pipe such as that shown at 30 in FIG. 4, the elastic limit ofth'e material will have been exceeded and the felted fibers torn apart somewhat in the zone 32 directly beneath the slot 14. In consequence, there is no longer any substantial'resil-ience at the hinge such as might otherwise tend to spring the sections apart once their free margins are closed,
Moreover, the margins 16 and 18 cannot be closed about the pipe 10 except by separating radially those portions of the respective sections which lie adjacent its minor axis. Thus, in FIG. 4, the inner surface 36 of section 8 has been spread by the pipe 30 away from the inner surface portion 38 of section 8 adjacent the slot 14. The molded pulp has an adequate elastic limit to accommodate this degree of displacement while retaining its resilient tendency to resume the original spacing between surface portions 36 and 38 as shown in FIG. 2. Accordingly, the surface portions 36 and 38 are in clamping engagement with pipe 30 while the intermediate surface area 40 which, if it engages the pipe, might weaken or interfere with this clamping action, is slightly clear of the pipe as is evident by examination of FIG. 4.
Similarly, the interior surfaces 42 and 44 of section 10 are clamped with that side of the pipe about which they are engaged. The clamping action springs outwardly the free margins 16 and 18 of the jacket so that the end surfaces 24 and 26 are no longer divergent as in FIG. 3, but are in substantial face contact to complete a snug and effective insulating enclosure of the pipe.
By way of example, and not by way of limitation, reference has been made to the preferred use of wood fiber or paper pulp as the material for the construction of jackets embodying this invention. Molded pulp is inexpensive and is an excellent insulating material and has the required elasticity. Pulp is readily molded, using known pressure differential techniques, to produce the form herein illustrated. In practice, it is found expedient to make the individual jacket units about one foot in length, using them end to end upon the pipe. At'the end of the series any excessive length in such a unit can readily be sawed oif.
The special jackets shown in FIGS. and 6 to accommodate the pipe fittings are similarly made. In the T jacket shown in FIG. 5, there are opposed internal surfaces 36, 38 and 42, 44- at as many different points as necessary to enclose Whatever fitting is to be jacketed. .The same is true of FIG. 6. In the FIG. 6 jacket, which is designed to enclose an elbow, the channel 14 along the bottom is extended upwardly at 14b clear to the top of the closed end of the jacket.
Sinw all of these constructions are usually molded on a screen, the interior surfaces have a pattern comparable to that of the screen cloth of the mold, the resulting surface having a high coeflicient of friction which is ideally suited to maintain clamping engagement with the jacketed pipe.
It will be observed that due to the weakening of the hinged joint 12 between the two sections of the jacket, each section acts individually in clamping engagement With ,the pipe. The unitaryconnection of the sections has importance only in handling, and is of little importance when the insulation is in use. So far as the engagement with the pipe is concerned, it is immaterial whether the sections are hingedly connected or separately fabricated and applied individually.
1. As a new article of manufacture, a pipe insulating member having an interior surface in the form of a channel of semi-elliptical cross section and having substantially opposed surfaces at a lesser spacing then the diameter of a pipe to be received therebetween, the insulating member having sufiicient resilience between said surfaces to permit the separation of said surfaces to receive a pipe and the clamping engagement thereof upon a pipe.
2. A pipe insulating member according to claim 1 in which the material thereof comprises molded felted fiber and the depth of the channel intermediate said surfaces exceeds the radius of said pipe.
3. As a new article of manufacture, a pipe insulating member comprising molded pulp and including unitarily connected semi-tubular sections having free margins separable to receive a pipe to be insulated, means hingedly said tubehaving an elongated internal cavity with a cross section in the form of an ellipse having relatively ma or and minor axes, the tube having free margins substantially symmetrical respecting said minor axis.
5. A tube of insulating material according to claim 4 interiorly provided with a channel opposite its free margins, said tube comprising a wall portion of reduced thickness along said channel, the tube having sections at opposite sides of the channel having clamping surfaces respectively adjacent the channel and the free margin aforesaid. I
6. As a'new article of manufacture, a pipe insulating member comprising a split tube of molded pulp and having free margins separable to receive a'pipe to be insulated, the tube having an internal cavity of cross sectional form corresponding to an ellipse with a minor axis extending toward said margins and a major axis transversely of the tube, said tube further being provided internallywith a longitudinal channel opposite said free margins and with a wall portion of reduced thickness outside of the channel which constitutes a hinged connection between sections of the tube respectively extending from the channel to respective free margins aforesaid, the molded pulp of the tube sections having substantial resilience andhaving pipe engaging surfaces respectively adjacent the channel and the free margin of each section,'said surfaces being clampingly engageable with a pipe receivable into the split tube between the free margins thereof upon the hinged separation of said sections and having a pipe diameter slightly in excess of the space between said pipe engaging surfaces on the minor axis aforesaid, wherebythe respective sections can be engaged with said pipe only by forcing the pipe between said surfaces againstthe resilient bias of the wall portions of the sections between their respective surfaces.
References Cited bythe Examiner UNITED STATES PATENTS EDWARD v. BENHAM, Primary Examiner. MORRIS SUSSMAN, Examiner.