April 28, 19121. KERR 7 1,802,766
PIPE OR TUBE JOINT Filed Dec. 8, 1927 I INVE'NTOR BY I W .V/%%SIRNEYS Patented Apr. 28, 1931 UNITED STATES PATENT OFFICE EOWARZD J. KERR, OF WESTFIELD, NEW ERSEY, COMPANY, OF BAYONNE, NEW JERSEY, A
ASSIGNOR TO THE BABCOCK & WILOOX CORPORATION OF NEW JERSEY rim on ma JOINT Application filed December 8, 1927. Serial No. 238,502.
1g liquid, a gas or a. superheated vapor, with a passage from the one pipe to the other, the walls surrounding the said .passage overlapping the joint between the two pipe sections and adapted to reduce the rate of heat exchange between the fluid in said passage and the material of the joint.
 Another object of my invention is the provision of a liquid supply pipe and a receiver to which it is connected, a Venturi tube being provided between the supply pipe and the receiver, the walls surrounding the passage in the Venturi tube overlapping the joint between the supply pipe and the receiver and adapted to reduce the rate of heat exchange between the fluid in said passage and the material of the joint.
 My invention will best be understood from the followingdescription and the annexed drawings, in which Fig.1 is a sectional view through a pipe joint and illustrating one em bodiment of my invention; Fig. 2 is a view generally similar to Fig.1. but illustrating a Venturi tube connecting the supply pipe to the receiver; Fig. 3 is a section generally similar to Fig. 2. but illustrating the walls around the Venturi tube surrounded by a water jacket, and Fig. 4 is a sectional view illustrating a fluid supply pipe connected to a drum or header.
 Like reference characters indicate like parts in the several views. In the form of my invention illustrated in Fig. 1, afluid supply pipe 10 is connected to areceiver 11, which in this case is a pipe sec- 5 tion, the supply pipe preferably being threaded as at 12, and the receiving pipe as at 13. In the embodiment illustrated, discs orflanges 14 and 15 are provided with central openings, the walls surrounding which are provided withscrew threads 16 and 17 which are received on thescrew threads 12 and 13 of thesupply pipe 10 and thepipe section 11..Suitable packing material 18 is preferably interposed between theflanges 14 and 15, and it will, of course, be understood that the flanges, may be secured together in any desired manner, usually by bolts.
 With ordinary constructions of joints, when there is a sudden drop in temperature in the liquid, gas or superheated vapor pass ing through the supply pipe, the metal at the joint and nearest to the fluid cools faster than the bolts and the relative contraction of the flange metal relieves the compression on thepacking. with the result that the packing material is likely to be blown out by the internal fluid pressure, or, in case there is a metal to metal joint without packing between the two, the seat pressure is relieved and in either case, a leaky joint may result.
 In accordance with my invention, means are provided forming a passage from the supply pipe tothe receiver, the passage being surrounded by walls which are adapted to reduce the rate of heat exchange from the liquid in said passage to the adjacent walls of the supply pipe and-the receiver at the joint, and thereby overcome the difliculties above referred to.
In the arrangement illustrated in Fig. 1,
.aplug 19 is rolled or otherwise permanentlyv attached'to the interior of thesupply pipe 10 at a distancefrom the joint, and through an axial opening in this plug, there extends anauxiliary tube 20, this tube being spaced from the interiors of the two pipe sections and overlapping the joint between thetwo pipe sections. Thetube 20 forms apassage 21 from thesupply pipe 10 to thereceiving pipe 11, thepipe 20 being surrounded by a more or less quiescent layer or jacket of fluid,
' one end of which is open to the fluid flowing in the pipe preferably at the receiver or down-stream end. This more or less dead jacket of liquid, gas or superheated vapor protects the ends of thepipes 10 and 11 from sudden changes in temperature and thereby avoids the difliculties due to leakage above referred to, because the thermal conductivity of such fluids is low.
 In the modification of my invention illustrated in Fig. 2, the adjacent ends of the supply pipe and the receiving pipe, and the means for fastening the two together, are the same as those illustrated in Fig. 1 and the same reference characters have been applied thereto. In the form here illustrated, a Venturi tube indicated generally at 23, connects theliquid supply pipe 10 to the receivingpipe 11. In the embodiment here shown, thepassage 24 in the Venturi tube is surrounded byWalls 25 cylindrical in form on their ex-' terior and adapted to fit snugly in the adjacent ends of thepipe sections 10 and 11 and formed of a material-which is a fairly good heat insulating material, such, for example, as porcelain, wood fibre,- or the material known to the trade as bakelite. The Venturi i tube thus serves to protect the joint between the supply pipe and the receiving pipe from sudden changes in temperature; at the same time, the Venturi passage reduces the resistance to the flow of the liquid as compared with an arrangement which causes sharp changes in the directions of the flow.
In the modification of my invention illustrated in Fig. 3, a Venturitube 23, generally similar to that shown in Fig. 2, is provided, but is surrounded by a jacket or layer offluid 26. which has little or no motion, communi'cating with the receiving pipe as in the 1 arrangement illustratedin Fig. 1. The -material of which the walls surrounding the Venturi passage are formed in this case need not be as good a heat insulator as in the arrangement illustrated in Fig. 2; in fact, the
venturi could, if desired, in this case be formed of metal because the high thermal resistance of the layer of fluid acts to prevent sudden changes in temperature of the joint material.
v In the arrangement illustrated in Fig. 4:, a liquid supply pipe'lO is secured by expansion or otherwise in anopening 27 in adrum 28, the tube preferably extending beyond the inner wall of the drum as illustrated. A Venturitube 23 of the character illustrated in Fig; 2 is received in the end of thesupply pipe 10 and prevents sudden changes in temperature which may occur in' the. fluid entering or leaving the drum or header from being communicated to the walls of the joint immediately surrounding the 'opening 27 thereby preventing leakage between the end of the tube and the drum itself. While I have illustrated a single fluid supply tube in Fig. 4, it will, of course, be understood that in practice when the tubes are used as econo-' mizer or superheater tubes for a steam boiler, 1
that a plurality thereof will preferably be provided entering the drum orheader 28, and the drum will usually be the steam and water drum of the steam boiler or the head- I .my invention is useful wherever fluids are utilized and where changes in temperature of the fluid occur.
I claim:
1. In a jointed pipe, a fluid supply pipe, a
fluid receiving pipe into which the fluid from said supply pipe is delivered, a joint being formed between the two said pipes, and atubular member seated and supported at one end in one of said pipes beyond said joint and having a free end extending into the other pipe, a continuous space being formed between aid tubular member and said supply pipe and receiving pipe and extending from the free end of said tubular member to 'the portion thereof which is seated and-supported in one of said pipes.
 2; In combination, a fluid supply pipe, a fluid receiving pipe into which the fluid from said supply pipe is delivered and to which said supply pipe isconnected, a Venturi tube seated and supported at one end in one of said pipes beyond said joint and having a free end extending into the other pipe, a continuous space being formed between the outer portion of said Venturi tube and said supply pipe and receiving pipe and extending rom the free end of said Venturi tube to the portion thereof which is seated and supported in one of said pipes.\ 3. In a jointed pipe, a fluid supply pipe, at fluid receiving pipe into which the fluid from said supply pipe is delivered, a joint being formed between the two said pipes; and a tubular member of heat insulating material seated andsupported at one end in one of said pipes beyond said joint and having a free end extending into the other pipe, a continuous space being formed between said tubular member and said supply pipe and receiving pipe and extending from the free end of said tubular member to the portion of said pipes.
4. In combination, a fluid suppl pipe, a
fluid receiving pipe into which the uid from said supply pipe is delivered and to which said supply pipe is connected, a Ventun tube of heat insulating material seated and supported at one end in one of said pipes beyond said joint and having a. free end extending into the other pipe, a continuous spacebein 6 formed between the outer rtion of sai Venturi tube and said supp y pipe andreceiving pipe and extending from the free end of said Venturi tube to the portion thereof which is seated and supported in one of 10 said pipes' HOWARD J KERR