Abstract: To provide a thermal insulation piping with no radially projecting part from a periphery thereof, so as to facilitate insertion of the thermal insulation piping into a pipeline or equivalent. In a thermal insulation tube 10 having a vacuum layer between an inner tube 11 and an outer tube 12, an evacuation port 30 for vacuum evacuation is oriented parallel with a longitudinal direction of the thermal insulation piping at an end of the thermal insulation tube 10. This construction can produce the thermal insulation tube 10 with no radially projecting part from a periphery thereof, thus providing improved workability when the thermal insulation piping is contained in the pipeline or equivalent. Further, a flexible pipe(s) 40 is/are preferably connected to the evacuation port(s) 30. This can allow increased positional tolerances in the connection of the evacuation port(s) to a vacuum evacuation device.

Abstract: A coupler for making a detachable bayonet connection between two sections of a flow path. The coupler includes male and female bayonet hub members that detachably connect the flow path sections. In one aspect of the invention, the coupler includes an internal vapor shielding flow path defined within the coupler by the interconnection of the hub members that operates to intercept and remove heat entering the coupler from the external environment. In this regard, the internal vapor shielding flow path may include at least one valve to vent at least a portion of the vapor shielding material external to the coupler from the vapor shielding flow path.

Abstract: An arrangement for cooling or heating of a flange bolt for turbines comprises one or more boreholes, that extend through the bolt, and inlet and outlet pipes that are connected to each end of the borehole. A cooling or heating medium such as air, steam or any other fluid flows through an inlet pipe into and through the borehole thereby cooling or heating the bolt, and exits from the borehole via an outlet pipe. The cooling or heating arrangement enables direct cooling or heating of the bolt itself and ensures stable bolting forces throughout the operation of the turbine. The flange bolts with this arrangement may be applied to gas turbines or steam turbines operated at elevated steam temperatures and pressures.

Abstract: The inside surfaces of pieces constituting an undersink pipe-covering system are formed with series of weakness zones, at spaced intervals and with associated distance scale indicia, to permit facile and convenient length determination and manual severance for adjustment, while affording aesthetic appeal.

Abstract: An electrical isolation connector subassembly for interconnecting adjacent tubular drill rods of a drilling system used in drilling bore holes in earth formations, the connector comprising an electrically insulative sleeve being sandwiched between two electrically isolated subassembly components, the sleeve providing an exterior gap between the edges of the spaced apart electrically isolated components, the exterior gap having a width of less than 50 cm.

Abstract: A high temperature pre-insulated piping system is shown which has a special water stop located along the length of the piping. The water stop has an internal disk which forms a pair of isolated chambers within the water stop. The internal disk is formed of a material which is impervious to the flow of water. As a result, the two internal chambers are isolated from one another and act as isolating elements to contain any breach in the exterior of the piping system to a specific location in the length of the pipe string.

Abstract: A high temperature pre-insulated piping system is shown which has a special water stop located along the length of the piping. The water stop has an internal disk which forms a pair of isolated regions within the water stop. The internal disk is formed of a material which is impervious to the flow of water. As a result, the two internal regions are isolated from one another and act as isolating elements to contain any breach in the exterior of the piping system to a specific location in the length of the pipe string.

Abstract: A system and kit for forming an inexpensive protective plenum around pipes subject to freezing is disclosed. The system uses tubes formed of thin, flexible material, such as plastic tubes, to form the plenum. The plenum may be installed in sections with the sections joined with rings or collars at the joints. The rings and collars may also be formed of inexpensive materials, such as plastics. The tubes of the plenum may be formed from plastic sheets by joining the sheets at opposite edges to form seamed tubes. The edges may be joined by tapes or adhesives. The tubes may be formed around existing piping for ease of retrofit installation. The plenum may be connected to a source of hot air, such as the duct work of the hot air heating system of a dwelling.

Abstract: An insulated transition spool apparatus for mounting unheading devices to pressure vessels, such as coker vessels, and enabling repetitive operation thereof is disclosed. The apparatus comprises an outer housing, an inner housing that encloses an insulating space between the inner and outer housing, a side feed entry aperture in each housing and a spool adapter flange to facilitate attachment of the spool to the vessel.

Abstract: A system and kit for forming an inexpensive protective plenum around pipes and related equipment subject to freezing on a mobile home is disclosed. The system uses thin, flexible material, such as plastic tubes, to form a first protective plenum around the pipes and to connect enclosures around a water box forming a second protective plenum. The first plenum around the pipes may be installed in sections with the sections joined with rings or collars at the joints. The rings and collars may also be formed of inexpensive materials, such as plastics. The second plenum may be connected to the first plenum or to a tube. The first plenum and the tube may be connected to a source of hot air, such as the duct work of the hot air heating system of the home.

Abstract: A connecting device for connecting first and second tubular pieces of an aircraft turbine engine may include a rigid ring with an at least approximately S-shaped cross section. The rigid ring is housed in a recess of an acoustic protection cellular core of the first tubular piece and includes: (1) an external branch, which bears against an external skin of the second tubular piece and is secured to the latter by a first fixing device; (2) a back, arranged facing an edge face of the cellular core; (3) a front arranged facing the first tubular piece, after the first and second tubular pieces have been connected; (4) a transverse branch connecting the back to the front; and (5) an internal branch connected to an internal skin of the second tubular piece and secured to the latter.

Abstract: An exhaust gas recycle (EGR) isolation flange that includes an annular body that defines a central aperture therethrough and a plurality of axially extending bosses that extend from the body is disclosed. Additionally, a method for coupling an exhaust gas recycle flange to an isolation flange is disclosed where the EGR flange is mated to the isolation flange by receiving an isolation flange boss within a boss receiving aperture of the EGR flange and by disposing a seal ring between the EGR flange body and the isolation flange body.

Abstract: A composite reinforced line pipe is manufactured by aligning first and second pipe segments each having a composite reinforcement wrapped circumferentially about a core, attaching the line pipes at a cut-back portion of their exposed core, wrapping a joint tape circumferentially about the cut-back portion, wrapping a resin reinforcement tape circumferentially about the joint tape, and curing the joint tape and resin reinforcement tape.

Abstract: A tubular assembly 10 is disclosed for passing fluids within a hydrocarbon recovery well. The tubular assembly 10 has an insulated connection 12 between insulated tubing segments 14, 16. Tubing segments 14, 16 are connected via a threaded connection, and the resulting joint 10 is insulated by an external insulating sleeve 18. The insulating sleeve 18 may have unitary construction, such that the sleeve 18 may only be installed or removed by first breaking apart the joint 10. Alternatively, the sleeve 18 may comprise a plurality of arcuate partial-sleeves, which may be assembled about or removed from the completed joint 10 without first breaking apart the joint 10.

Abstract: A composite reinforced line pipe is manufactured by aligning first and second pipe segments each having a composite reinforcement wrapped circumferentially about a core, attaching the line pipes at a cut-back portion of their exposed core, wrapping a joint tape circumferentially about the cut-back portion, wrapping a resin reinforcement tape circumferentially about the joint tape, and curing the joint tape and resin reinforcement tape.

Abstract: A method for forming and attaching a clamping collar to a pipe configured for forming a pipe section in a concrete pumping line for carrying of fluid concrete includes the steps of placing a sleeve on the pipe to provide a heat transfer limit area between the sleeve and the pipe; welding the sleeve to the pipe; heat treating the pipe; and assembling a collar to the sleeve and welding the collar to the sleeve.

Abstract: A duct to receive duct wrap is provided with a plurality of posts at different locations on and upstanding from the post to protrude through the duct wrap. Wrap retainers fit onto the post over the duct wrap securing the duct wrap on the duct.

Abstract: An adapter blank is provided which is adjustable in size to join generally tubular structures of different diameters, such as pipe insulation cladding, together. The adapter blank includes a tapering wall having a rim defining a larger diameter matching larger diameter pipe insulation cladding to be joined by the adapter. An overlapping edge extends away from the rim. Graduations are located at various different constant distances away from the rim. Indicia, such as numbers, are preferably provided adjacent at least some of the graduations to indicate the various different smaller diameter pipe insulation cladding sizes. The adapter blank is cut along the graduation corresponding with the smaller diameter pipe insulation cladding to be joined with the adapter. The adapter blank is thus modified into a finished adapter ready for installation joining together pipe insulation cladding, or other tubular structures of different diameters; or terminating an end of pipe, tank, vessel or other tubular structure.

Abstract: A unique protective cover system for hot water pipes and other pipe installations and which relies upon a plurality of jackets capable of being disposed about the pipes. In one embodiment of the invention, there is provided an under-sink heat protective cover system having a first J-shaped jacket to cover a J-shaped pipe arrangement or J-trap and a portion of straight pipe cover to cover the waste arm pipe in an under-sink pipe installation. Moreover, a unique coupling mechanism in the mating jackets allows one jacket to be fitted and tightly connected with the other jacket. Each of the jackets are slit longitudinally so that they can be spread apart at the slit and fitted on the pipes of the installation. A unique locking system is provided to retentively and tightly hold each jacket around a pipe section. Moreover, in another embodiment, fiber fastening strips are located adjacent the opposed edges of the slit for quickly releasably locking together with two edges of the jacket adjacent the slit.

Abstract: The present invention provides a joint (6) between insulated pipes (4), which comprises: (a) two transport pipes joined together; (b) insulation on each transport pipe which ends short of the joint; (c) a casing surrounding the exposed portion of pipe; (d) a sleeve which provides a seal between an end of the casing and the adjacent pipe insulation, wherein the sleeve comprises recoverable polymeric material (1) coated at discrete regions with a sealant (3) and/or a heat-activatable adhesive (2), (preferably with the sealant (3) bridging the end of the casing and the pipe insulation to form a seal therebetween which can accommodate movement of the casing relative to the pipe insulation, and the adhesive (2) forming substantially annular bonds between the sleeve and the casing and between the sleeve and pipe insulation), characterised in that at least one region (4) of the sleeve, preferably between the sealant-coated and the adhesive-coated regions or at the edge of the sleeve, remains uncoated to provide a re

Abstract: An insulation piece for a pipeline conveys electrically conductive liquids from a point that is at a ground potential to a point connected to a high voltage. The liquid is conveyed discontinuously by portion-by-portion transport by the carriage flow of the liquid being interrupted. The insulation piece is periodically free of liquid, corresponding to the interruptions in the carriage flow. The insulation piece is a hollow body, and its unobstructed width is equal to or greater than that of the pipeline. Connecting pieces for connecting to the pipeline are provided on the end faces of the insulation piece, which are closed in places by terminating elements, and which connecting pieces are of the same diameter as the adjacent pipeline. The connecting pieces pass through the terminating elements, rest against them to form a seal, and each have a toroidal-form attachment on the outside at their inner end.

Abstract: The present invention relates to an ventilation duct construction and a method which increases the fire-retardant capability of a ventilation duct. According to the invention, an improved fire-retardant capability of a ventilation duct or sound absorber is obtained by providing the ventilation duct with a shielding sheet at a distance from the same so that an air gap is formed therebetween. The time during which the outside temperature of the construction can be kept down is prolonged, while the construction remains compact.

Abstract: A dielectric joint for pipes, particularly for underground pipes, comprises a male head of a first pipe which enters a mating and mutually opposite cup-shaped female head of a second pipe; a sealing insulating means is interposed between the pipes and is externally extended on the first pipe by an extent which reaches beyond the inlet edge of the female head and internally forms a tight-fitting cladding of the first and second pipes for a longitudinal extent which is at least equal to the overall length of the joint.

Abstract: A decoupling hose for mounting in an exhaust pipe of a motor vehicle engine, the hose comprising in particular an inner mechanical portion for guiding the flow of exhaust gas through the hose, a sealing portion forming an outer casing that is leakproof relative to exhaust gas, an intermediate portion providing thermal insulation, and means for connecting the ends of the inner and outer portions of the hose to the exhaust pipe, wherein the inner mechanical portion of the hose is constituted by a metal tubular part in the form of sheet metal joined by dual folded seam connections that are very loose.

Abstract: A method and a device for connecting parts of an exhaust gas system which comprises at least one metal tube formed from a bellows and optionally further parts disposed coaxially within and/or outside of the bellows and at least one further system part to be connected to the metal tube, are characterized in that one end of a short connecting tube is inserted positively in an end of the metal tube and the other end is inserted positively in the system part to be connected to the metal tube, and the system part is moved to the end of the metal tube facing the system part, thereby leaving a gap, and the system part, the connecting tube and the metal tube being connected from the outside in one working step.

Abstract: This invention relates to a method of repairing a moisture barrier separating a paper machine dryer drum from the dryer journal. Such processes of this type, generally, involve filling the cavity between the dryer drum steam intake pipe and the dryer journal with a flowable moisture barrier material. The flowable moisture barrier seals leaks in the dryer journal moisture barrier.

Abstract: A self-covering element for covering a pipe joint comprising of a deformable, hollow insulating element having a first portion and a second portion attached at an angle to one another. A longitudinal slit runs the length of the first and second portions, and a pressure sensitive adhesive with a removable release film is adhered to the longitudinal slit. The deformable insulating element allows for the entry of the pipe joint through the longitudinal slit, and surrounds the pipe joint. The pressure sensitive adhesive then seals the longitudinal slit and the pipe joint into the hollow cavity once the release film is removed.

Abstract: An insulation system for shafts through which hot gases flow, especially exhaust gas shafts of gas turbines has an insulation layer (20, 40) as well as a flat cover (26, 39), which holds the insulation layer (20, 40) and covers it against the gas flow. The cover (26, 39) is guided by bearing rails (21, 41). In such an insulation system, the number of spacers (22, 23, 24; 47, 48, 49) by which the bearing rails (21, 41) are fastened to a shaft wall (25, 50) shall be minimized. Furthermore, the insulation system shall be able to be manufactured with a high degree of prefabrication in the workshop and with low assembly effort at the construction site. The bearing rails (21, 41) are fastened to the shaft wall (25, 50) with a fixed mount (31, 51) and at least one movable mount (32, 52).

Abstract: A method of joining the ends of two thermal insulated pipes or conduits where each conduit has an inner pipe that extends axially beyond a middle tubular layer of thermal insulation material and an outer tubular layer of protective jacket. Before the ends of the inner pipe are welded together, an end cap blank having a central aperture is fit onto each inner pipe until it covers the exposed end of the middle and outer layers. Each end cap blank initially has the area of its central aperture pressed and deformed axially to form a tapered collar. Subsequently the inner pipe of a conduit presses and further deforms the tapered collar to define a substantially axially extending collar that is sealingly fit about the inner pipe protruding therethrough to prevent escape of toxic gases from the insulation layer during the welding process, as well as to protect the insulation layer from moisture in the environment.

Abstract: A pipe coupling for coupling together two pipes in a fluid-tight manner includes a tubular casing, a tubular sealing gasket located within the casing, and screws for tensioning the casing around the gasket. The casing includes an inner tubular casing and an outer tubular casing, both of metal. A layer of fire-resistant thermally-insulating material is disposed between the inner and outer casings to form a fire shield.

Abstract: The present invention relates to an ventilation duct construction and a method which increases the fire-retardant capability of a ventilation duct. According to the invention, an improved fire-retardant capability of a ventilation duct or sound absorber is obtained by providing the ventilation duct with a shielding sheet at a distance from the same so that an air gap is formed therebetween. The time during which the outside temperature of the construction can be kept down is prolonged, while the construction remains compact.

Abstract: A pipe insulation coupling for coupling adjacent facing ends of elongated cylindrical pipe insulation tubing encased around a fluid pipe includes an elongated body extending longitudinally between a first end and a second end. The elongated body includes a pair of C-shaped clam shell portion interconnected by a living hinge for pivotal movement between an open position for receiving the pipe and a closed position clamped around the pipe and insulation tubing. Each clam shell portion includes an outer tube wall and an inner tube extending longitudinally between the first and second ends and defining a channel therebetween for receiving the adjacent facing ends of the insulation tubing. A planar wall interconnects the outer tube wall and the inner tube wall midway between the ends to abut the adjacent ends of the insulation tubing.

Abstract: A coupling assembly includes a first coupling member, a second coupling member, and a coupling nut disposed over a portion of the second coupling member and threadingly engaging the first coupling member to retain the first and second coupling members together. An insulation blanket encloses the coupling nut, and a retention strip having a first end attached to an inner surface of the insulation blanket and a second end attached to the coupling nut is provided to prevent loosening of the coupling nut.

Abstract: A method and apparatus for protecting exposed pipeline joints on weight coated pipelines used in offshore applications. The method allows quick installation on a lay barge where pipeline sections are being welded together for offshore installation. The method does not require a long cure time before handling. The method protects the corrosion coating on pipeline joint sections not covered with weight coat by forming a pliable sheet of polyethylene into a cylindrical cover material sleeve over the exposed pipeline joint connection. Polyurethane chemicals are reacted to form a high density foam which fills an annular space between the pipe and the cover material sleeve. The cover material sleeve and the foam form a composite system to protect the joint connection whereby the foam provides continuous compressive reinforcements and impact resistance and the sleeve provides puncture resistance and protection from water jetting/post trenching operations plus abrasion resistance.

Abstract: A concrete flow line made up of a plurality of end to end pipe sections with pipes connected to each other by a coupling assembly provides for carrying abrasive fluid concrete to a deposit site. The coupling assembly includes an insulating thin sleeve slid over the connecting end of the pipe and spaced from the pipe to form a heat insulating air space therebetween. The thin sleeve is welded to the pipe prior to the hardening of the pipe. After the sleeve is welded in place the inner wall of the pipe is hardened using an induction coil for concentrating of the heat within the inner wall portion in combination with a quenching unit to affect the desired hardening while maintaining an outer ductile wall portion to which the sleeve has been actually welded. A clamping collar or coupler is welded to the sleeve after hardening and forms a connecting end for receiving of a clamp unit which interconnects the adjacent pipe and pipe sections.

Abstract: An exhaust decoupler system for motor vehicles includes: a sleeve through which exhaust gas may pass from the engine; a couple of retainer members oppositely positioned from the exhaust pipe and engine, one member engaged with the outer side of the sleeve, at which end the rims are circumferentially bent; bellows between the rims of the inner retainer members, for absorbing the bending and expansion to maintain the exhaust gas to be airtight; outer retainer members located externally the inner retainer members, both ends engaged with the inner retainer members, inner side to be opened toward the center; a guide ring member for dividing the inner retainer members and outer retainer members to symmetrically form first pockets and second pockets, and for surrounding the bellows; and an inner buffering member and an outer buffering member in the form of loop to be filled within in the first pockets and the second pockets.

Abstract: A pipe in pipe assembly. A coupling is used to join the ends of the inner pipe. The inner pipe is centralized within the inner pipe to provide axial resistance but minimum restraint transverse to the axis of the assembly. This provides sufficient flexibility of the inner pipe to accommodate the necessary tolerances to permit the use of the coupling. The inner pipe may be centralized within the outer pipe by the use of foam injected between the inner and outer pipe and a corrugated web sleeve around the ends of the inner pipe. The inner pipe may also be centralized within the outer pipe by the use of a corrugated web bulkhead that fits around the inner pipe and within the outer pipe.

Abstract: A flexible mechanical joint is disclosed for joining a first elongated structural section with a second elongated structural section. The joint is compressible and expandable at least along a substantially longitudinal direction upon movement of at least one of the first and second sections. The joint includes a first connecting portion fixedly attached to the first section and a second connecting portion fixedly attached to the second section. The joint also has a flexible member that connects the first connecting portion with the second connecting portion and is positioned between the two connecting portions. The flexible member is shiftable upon relative longitudinal movement between the first and second sections. At least one of the first and second connecting portions includes an anchoring member frictionally engaging one of the first and second sections and including a lip that is secured into the one section.

Abstract: A system and method for electrically isolating conduit connections in a gas line system for residential, commercial or industrial applications. Gas line conduit of standard configuration is cut to length and upset at one end to create an annular flange of increased diameter, which then is machined to a desired configuration having annular ridges and flat and tapered surfaces. The other end of the conduit is machined in a standard thread configuration. The flanged portion of the conduit is then placed in an injection molding machine and receives a non-conductive elastomeric, molded seal thereover which includes a tubular pilot portion. A coupling nut slipped over the conduit may then join the conduit to conventional gas line valves, meters or the like in a completely electrically insulated connection.

Abstract: A pipe joint is provided whereby fluid pipelines, such as exhaust pipes, or the like, can be connected hermetically, in such a manner that the relative angle therebetween can vary, while ensuring satisfactory manufacturing precision of the sealing surface of a ring-shaped sealing ring.

Abstract: The method of forming a field joint around the bare joint of two joined insulation covered pipes includes providing a first angular cut back in the coating to expose the end of a pipe and providing a second cut back in the coating to provide an annular band of the coating of a lesser diameter than the coating on the pipe. A thin coating of polyurethane may then be applied over the first and second cut backs and a recess provided in the band of coating. A mould may then be secured around the lesser diameter band, and polyurethane pumped into the mould in a sufficient amount to form a field joint which extends into the second cut back and lies flush with the coating of the pipes so as to allow for reeling and laying of the pipe without snagging. The field joint can be located around the bare joint and includes a polyurethane infill recessed into the insulated coating of the pipes such that infill lies flush with the surface of the coating on the pipes.

Abstract: A connection arrangement is provided for a mineral-insulated conduit with two ends to at least one tube-shaped structure, wherein at least one end is arranged partially overlapping with a tube-shaped structure and is affixed by welding or soldering, and wherein a sheath surface is arranged in the region of the overlap. The problem results of making available a connection arrangement for a mineral-insulated conduit to a tube-shaped structure, which is simple to produce and mechanically stable. The problem is solved in that the sheath surface has a structured surface, the end of the mineral-insulated conduit and the tube-shaped structure contact each other on all sides in the region of the overlap, and the contact surface is smaller than the sheath surface beyond the contact surface.

Abstract: The invention is directed to a double-wall steel pipe joint. Each section of double-wall steel pipe has a steel outer casing and a steel inner carrier pipe. The completed joint comprises a steel joint ring fitted within the annular space at the end of each double-wall steel pipe section. The combination of locking serration and epoxy bonding join and seal the inner steel pipe to the bore of the joint ring, without welding. Welding joins the ends of the sections of outer casing.

Abstract: Prefabricated insulated pipe sections are constructed of an inner pipe surrounded by a concentrically-positioned outer pipe. End portions of the inner and outer pipes are joined with bellow members so that an annular space is defined. A portion of the inner pipe is wrapped with layers of insulation material with inert insulating granules positioned between the layers. The annular space is partially evacuated to below atmospheric pressure. Multiple pipe sections may be joined by their inner pipes through brazing or other known methods. The joints and neighboring bellow members on abutting pipe sections are covered by clam shells that are sealed and filled with insulation.

Abstract: A piping system for conveying one or more product flow lines within an outer casing includes insulation members on the product flowline(s) to prevent heat lost and an improved spacer arrangement forming an interface between the product flow lines and the casing to prevent damage to the casing and flow lines as well as reduce friction when the flow lines are pulled through the casing. The insulation members includes a plurality of halves that can be assembled together circumferentially and end-to-end. In one embodiment, a frame carries a U-shaped insulation member that is polymeric and foam filled. The frame is ballasted so that it can be towed to a job site underwater yet buoyant and above the seabed, then lowered onto the pipeline by flooding the ballast tanks.

Abstract: A cryogenic coupler includes a socket and a plug that can be detachably inserted into the socket. The socket and the plug have passages for passing a cryogenic medium therethrough, and are provided with valves for blocking the respective passages when the plug is disconnected from the socket. A seal assembly is arranged between opposite end surfaces of the socket and the plug. The seal assembly has a resilience characteristic that is substantially uninfluenced by the cryogenic temperature, and thus prevents leakage of the cryogenic medium to outside, when passages in the socket and the plug are connected to each other. The coupler allows a facilitated connection and disconnection of the passages, even under a low temperature condition.

Abstract: A method and system for dispensing cryogenic fluids, such as liquified natural gas (LNG), using a swivel bayonet joint interconnecting first and second sections of cryogenic pipe. The swivel bayonet joint includes a male bayonet joint and a corresponding female bayonet joint. An insertion stem of the male bayonet joint is dimensioned to have a very high tolerance fit within the receiving sleeve of the female joint that extends a sufficient length for formation of a vapor trap by the cryogenic fluid between the insertion end of the stem and the clamp end of the receiving sleeve. The vapor trap prohibits movement beyond the vapor trap of any cryogenic fluid passing through the joint, consequently, elastomeric seals in the bayonet joint remain insulated from extremely cold temperatures of the cryogenic fluid.

Abstract: A modified expansion joint to provide a transition from one conduit to an adjacent conduit. The expansion joint includes a flexible coupling member and an angled transition leg having insulation on both sides thereof. The flexible coupling member takes up any variations in dimensional differences between the adjacent conduits. The transition leg provides a gradual thermal transition from a hot upstream conduit to a downstream conduit at a lower exterior surface temperature.

Abstract: An interfitting modular metal duct made up of elements forming an inner d, pairs of elements being united by respective collars, sealing between the two elements being provided by a lip gasket and a fold chamber mounted in the female end of an element and bearing against the outside surface of the corresponding male portion.

Abstract: An electrically insulating gap subassembly for inclusion in a pipe string (30) comprising a pair of tubular members (90, 98) having an electrically insulating isolation subassembly (94) threadably disposed therebetween is disclosed. The electrically insulating isolation subassembly (94) has an anodized aluminum surface that provides electrical isolation to interrupt electrical contact between the two tubular members (90, 98) such that electromagnetic waves (46, 54) carrying information may be generated thereacross.