US2202493A

US2202493A - Securing device

Info

Publication number: US2202493A
Authority: US
Inventors: George T Jacocks
Original assignee: Lummus Co
Current assignee: CB&I Technology Inc
Priority date: 1939-02-17
Filing date: 1939-02-17
Publication date: 1940-05-28
Anticipated expiration: 1957-05-28

Description

May 28, 1940.

G. 'r. JAcocKs SECURING DEVICE Filed Feb. 17, 1959 INVENTOR B 620796 (jg/ks ATTORN EY tubes to another part of the tubes.

' Patented May 2a, 1940 UNITED STATES PATENT OFFICE 2,202,493 sncuamo DEVICE George T. Jacocks, Larchmont, N. Y., assignor to The Lummus Company, New York, N. Y., a corporation of Delaware Application Eebruary 17, 1939, Serial No. 256,935

5 Claims.

This invention relates to securing devices for detachably securing plates .to vessels and more particularly, to floating head cover sealing devices for tubular type heat-exchangers having a I tube bundle within a shell.

In heat exchanger construction of the typical shell and tube type, an internal cover is secured shell, while the tube bundle and floating tube sheet are removed from the other end of the shell. While my invention is of particular im-, portance in securing the cover to the floating tube sheet in huch relation, it will also be obvious that it may be used for any similar purpose.

The principal object .of my present invention is toi rovide an improved pressure vessel construction having a removable cover member detachablysecured to a plate, such cover member 35 being held sealed irrespective of temperature changes and pressure conditions, and which is readily detached when desired.

Another and more specific object of my invention is to provide a holding clamp mechanism in'a heat exchanger for detachably holding a cover to a floating tube sheet with aminimum increase in diameter over the maximum tube diameter and in such positive manner that there is no tendency of the cover to be displaced from the tube sheet. 7

Another object of the invention is to provide an improved seal for-a floating head cover of a heat exchanger so that the cover may be sealed in pressure tight relation to the under side of a floating tube sheet with the seal on top of the plate, such seal including split clamps and a solid securing ring which may be entirely removed from the plate, the clamp members havinga minimum thickness, maximum strength,

and being simple in construction and being firmly line i,--l. of Figure 2, of a heat exchanger em'- bodying a preferred form of the invention; and

I I. Figure 2 is 'a top plan view, partially broken away, of the top of the floating tube sheet cover.

My invention, although applicable to any type of sealing device which must be clamped to a plate or shell or member having an opening therein in such a manner that the cover and 6.

clamp can be removed from one side of the plate or one end of the shell, is' of particular importance in securing the cover to the floating tube sheet of a heat exchanger. For this reason, it will be described in such connection, although no limitation is intended thereby.

The heat exchanger shell Ill normally has a tube bundle 35 anchored at the channel end (not shown) and in order to provide for the necessary expansion, the floating tube sheet as, to which 1 the other ends of the tubes are secured, is completely movable within the shell cover l8. Circulation of fluid from one part of the tube bundle 35 .to the other is accomplished'by a floating tube sheet cover 40 and this is sealed by gasket 44 to the edge of the tube sheet 36.

Under ordinary circumstances, it is occasionally necessary to remove the entire bundle from the shell of the heat exchanger, which is accomplished by removing the tube bundle from the fixed or opposite end of the heat exchanger. It is therefore necessary that the floating tube sheet 36 be of smaller diameter than any other part of the shell through which it must pass. It is of course, also essential that the floating tube sheet cover Ill be adequately secured to the floating tube sheet 36, and without an excessive size of shell cover It. In accordance with my invention, I provide sectional c-clamp members 38 which are conveniently"semi cylindrical members forming a ring split on the major diameter as shown in Figure 2. 'IhisC-clamp. when in place, not only under-lies the floatingtube sheet 36, and has portion 38a engaging the tube sheet, but the cclamp projects substantially above the tube sheet cover 40 and ovef lies'the cover as well as the bull ring ll' as shown at 38b.

The underlying and overlying portions 38a and "b are preferably laterally inwardly projecting angular gripping edges which grip the tube sheet 30 and bull ring 4|.

The upper and lower edges of the c-clamp ll are drawn into the gripping position by thebolts I! which arelscrew threaded therein and engage the top of the cover 4'. The more the reaction longitudinally due to the outward movement of the bull ring, the greater the gripping tendencyof the O-clamp members on the tube sheet and bull ring. Both the tube sheet a and the bull ll 2 1 ring ll have the cooperating peripheral channels 360. and lla for this purpose.

The angle of inclination of the grooves 36!: and a may be in the neighborhood of 15 which will prevent the O-clamp sections 38 from moving away from the secured parts. It is of course obvious, however, that right angle channels and tongues could be substituted as far as holding reaction is concerned, but there would not be any increase in tightness of the C-clamp members laterally of the tube sheet. Such construction is an alternative, but not as satisfactory.

The construction is far superior to constructions heretofore used in that there is a continuous contact between the C-clamp members and the tube sheet and bull ring which extends through substantially 360. This exists both at the top and at the bottom and the C-clamp members can not come loose. Longitudinal clearance over the shell flange Illa. may also be reduced to a minimum as the slight taper of the enga ing parts is such that backing off the bolts 42 will quickly free the clamp sections. It is also possible to effectively control the thickness of the parts for the necessary strength. The machining of the Q-clamp members is extremely simple, parts being preferably made reversible. The bull ring has the necessary metal for screw threading and excessive top flanges on the clamp members are unnecessary.

This construction has another important advantage over heretofore proposed arrangements inasmuch as it is possible to reduce the diameter of shell 10 to a minimum as the clearance can be relatively close. The walls of the c-clamp are in tension, and all of the metal is eflective. No extra thickness is required for bolts and this would reduce the shell diameter several inches on a 24' diameter high pressure unit. The flange diameter is also reduced to the same extent.

The simplicity, superior strength, reduced size and low cost of the bull ring and C-clamp members commends its use both on internal as well as external joints. It is especially useful on internal joints, however, as it is not affected by heat or pressure or time as the sealing force is directly reacted by balancing forces. Where inspection is diflicult, its use is most beneficial.

While I have shown and described a preferred form of embodiment of the invention, I am aware that other modifications may be made thereto and I therefore desire a broad interpretation thereof within the scope and spirit of the description herein and of the claims appended hereinafter.

I claim: g

1. In a heat exchanger ,of the class described having a shell, a tube bundle therein, a tube sheet for one end of the tube bundle sutliciently smaller than said shell to be easily removable therethrough, and a cover for said tube sheet having a rim engaging the outer face of the tube sheet, the

-combination of a sectional ring in clamping en- Basement with said tubesheet, removable means engaging said sectional ring and tending to hold it together, and adjustable members extending between said cover and said removable means and exerting a. force therebetween for clamping said cover and tube sheet together.

2. In a heat exchanger of the class described having a shell, a tube bundle therein, a tube sheet for one end of the tube bundle sufiiciently smaller than said shell to be easily removable therethrough and a cover for said tube sheet havin a rim engaging the outer face of the tube sheet, the combination of a sectional ring surrounding said cover and in clamping engagement with said tube sheet, a continuous ring engaging said sectional ring to prevent canting of said sectional ring when said cover and tube sheet are clamped together, and means for clamping said cover and tube sheet together.

3. In a heat exchanger having a shell, a tube bundle therein, a tube sheet for one end of the tube bundle, and a cover for said tube sheet having a rim engaging the outer face of the tube sheet, the combination of a clamping element of separate channel cross-section portions encircling the tube sheet and cover, the flanges ofthe element extending radially inwardly to overlap the opposite faces of the tube sheet and cover for locking them together, and a continuous ring within the channel of the clamping element having means interlocking with the flanges of the clamping element to hold said portions inwardly.

4. In a heat exchanger having a shell, a tube bundle therein, a tube sheet for one end of the tube bundle, and a cover for said tube sheet having a rim engaging the outer face of the tube sheet, the combination of a plurality of thinwalled segments embracing the peripheries of the tube sheet and cover rim for clamping them together, said segments jointly forming a complete ring, said segments having inwardly projecting gripping portions, continuous ring means engaging part of-said gripping portions, and adjustable members cooperating with said ring means for forcing another part of said gripping portions into engagement with the tube sheet.

5. In a pressure vessel of the class described, a member having an opening therein, a cover for said member and means to secure said cover to said member, said means including partially cylindrical c-shaped clamp devices, said devices being movable laterally to a position to engage under said member and over said cover, and means to draw said clamp devices laterally inward toward said cover and member, said means including a ring, adjustable elements in said ring engaging the cover, and laterally inwardly projecting grooves on the inner surface of the member and the outer surface of the ring, said clamp devices having inwardly extending gripping edges engaging in said grooves.

GEORGE T. J ACOCKS.