Abstract: The present invention relates to a downhole tool head (1) for mounting onto a downhole tool (10) for drilling in a formation downhole or for releasing precipitated solids (2), such as ice, scales or the like, in a cavity fluid in a pipeline, a casing (3), a well or any other cavity downhole. The downhole tool head comprises a hollow cylindrical body (4) with a circumferential wall (5) extending from a base part of the body, the circumferential wall having a circumferential rim (6) in its end opposite the base part. The circumferential rim (6) comprises a plurality of edges (8) for cutting, grinding, drilling and/or milling, and the base part has a plurality of through-going holes (9) for letting cavity fluid comprising precipitated solids pass the holes.

Abstract: A grapple for use in an overshot has a tension ring with a reduced helix diameter. However, the helix diameter is not reduced on either sides of the control finger slot to allow the grapple to remain in contact with the control. In the alternative, a composite helix member may be utilized. Another embodiment comprises the inclusion of expansion blades on the inner diameter (“ID”) of the tension ring which allow the grapple to expand substantially before the fish reaches the segments. Another embodiment provides for a control with an offset finger to allow the guide thread ID to be smaller than the bowl helix major ID. Yet another embodiment provides a spiral grapple having grooves along its axis to provide the ability to catch a larger range of fish.

Abstract: A remotely operated lifting top drive cement head has a high tensile strength and the ability to swivel or rotate. The cement head permits selective launching of darts, setting plugs, balls or other objects which can be held in place within the cement head without being damaged or washed away by slurry flow, but which can be beneficially launched as desired. The cement head can be remotely operated without requiring personnel to be lifted off the rig floor to actuate the tool or observe tool status.

Abstract: A blowout preventer assembly comprising an annular blowout preventer having an annular packing unit and an actuator operable to reduce the internal diameter of the annular packing unit, wherein the assembly further comprises a stripping sleeve having a tubular elastomeric sleeve which in use is positioned generally centrally of the packing unit so that the packing unit surrounds at least a portion of the elastomeric sleeve.

Abstract: A downhole tool with a swellable mantle is configured for insertion of a cable into a longitudinal slit in the mantle. An arcuate groove is formed in an outer surface of the mantle corresponding to a displacement caused by the inserted cable, so that the displacement is counteracted and the outer surface of the mantle remains smooth.

Abstract: Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. In one embodiment a method of plugging a wellbore is described. The method comprises providing a set-delayed cement composition comprising pumice, hydrated lime, a cement set retarder, and water; activating the set-delayed cement composition to produce an activated set-delayed cement composition; introducing the activated set-delayed cement composition into the wellbore; and allowing the activated set-delayed cement composition to form a plug in the wellbore that has a permeability of less than 0.1 millidarcy.

Abstract: In downhole treatments in the oilfield, ball sealers seated in perforations may not fully seal and may leak fluid through gaps and asperities between the balls and the perforations. A method is given for improving the sealing of ball sealers in perforations by adding a sealing agent that forms a plug in the gaps and severely restricts or eliminates fluid flow. The sealing agent is preferably degradable or soluble, malleable fibers slightly larger than the gaps. Optionally, the particles may be non-degradable, rigid, of different shapes, and smaller than the gaps but able to bridge them. Mixtures of sealing agents may be used. The sealing agent may be added with the ball sealers, after the ball sealers, or both.

Abstract: A device having a hard seat support disposed with a hard seat to reduce or prevent buckling, bursting, and/or permanent deformation of the hard seat that compromises the seal across the hard sealing surface and flapper sealing surface interface. The hard seat support may be positioned along an inner periphery of the hard seat or in direct contact with an outer periphery of the hard seat.

Abstract: A component of a wellbore tool comprises a plurality of compartments disposed over a body of the component and a coating disposed over at least a portion of a surface of the body. Each compartment comprises a healing agent formulated to form or catalyze the formation of a barrier upon release from the compartment. A matrix material separates the plurality of compartments. Methods of forming wellbore tools include forming a body, forming a plurality of capsules, and forming a coating comprising the capsules over the body. Methods of utilizing a wellbore tool in a subterranean borehole include contacting at least a portion of a body with a fluid comprising a healing agent formulated to a barrier. Coatings for wellbore tools include a fiber comprising a plurality of discrete cells and a matrix material contacting and at least partially surrounding the fiber. Each cell comprises a healing agent.

Abstract: In some aspects, techniques and systems for simulating well system fluid flow are described. Multiple subsystem models each include fluid flow variables and represent well system fluid dynamics associated with a sub-region in a subterranean region. The subsystem models are connected by one or more junction models. The junction models represent interactions among the subsystem models. For each of the subsystem models, an elimination of internal variables of the subsystem model is performed to express the internal variables in terms of junction variables of the junction models. The junction variables are solved based on the junction models. The internal variables of the subsystem model are solved based on the solved junction variables.

Abstract: A packer and screen assembly for a gravel or filter-packed well including a cylindrical shaped screen and a packer ring attached to an upper portion of the screen, with the packer ring positioned above an annular space surrounding the cylindrical-shaped screen and including an access opening having a closed configuration that substantially closes off the annular space and an open configuration that permits access to the annular space to fill the annular space with gravel or filter material. A method of filling or refilling a well with gravel or filter pack material is also provided including the steps of accessing the packer and screen assembly positioned within the well, transitioning the access opening in the packer ring from the closed configuration to the open configuration, and delivering gravel or filter pack material through the access opening and into the annular space surrounding the cylindrical-shaped screen.

Abstract: A cartridge-type wellbore screen includes a fluid tracing material carried by the wellbore tubular and mounted at a mounting site spaced from an opening through the screen wall to the screen's inner diameter and outwardly of the inner diameter, the mounting site being positioned such that a fluid flow path is restricted to be from the mounting site, along the outer surface of the screen and through the opening before entering the inner diameter. The screen can be used for treating wellbore fluids.

Abstract: An apparatus for screening earth formation components and a method of making the apparatus, the apparatus including a base pipe configured to allow the passage of formation fluid therethrough, and a foam layer disposed radially outwardly of the base pipe and configured to allow the passage of formation fluid therethrough and minimize the passage of formation solids therethrough, the foam layer-including a plurality of hollow structures forming windows therebetween.

Abstract: A downhole completion assembly for sealing and supporting an open hole section of a wellbore includes a sealing structure movable between a contracted configuration and an expanded configuration, wherein, when in the contracted configuration, the sealing structure is able to axially traverse production tubing extended within a wellbore. A conveyance device is coupled to the sealing structure and configured to transport the sealing structure through the production tubing and to an open hole section of the wellbore. A deployment device is operably connected to the sealing structure and configured to radially expand the sealing structure from the contracted configuration to the expanded configuration when the sealing structure is arranged in the open hole section.

Abstract: Apparatus and methods for conducting well-related fluids are disclosed. The apparatus and methods may be used to mitigate erosion of fluid handling equipment by fluids associated with hydrocarbon wells. An exemplary apparatus comprises: an upstream conduit including an upstream fluid passage for receiving and conducting well-related fluid; a choke member including a choke fluid passage; and a downstream conduit including a downstream fluid passage in fluid communication with the upstream fluid passage via the choke fluid passage. A cross-sectional area of the downstream passage may be greater than a cross-sectional area of the upstream passage to allow expansion of the fluids passing through the choke such that the average velocity of such fluids may not exceed a threshold velocity selected to mitigate erosion of the downstream conduit.

Abstract: A method for preventing damage to a downhole pump impeller of a downhole pump includes setting a rotatable part of a downhole pump to a selected depth, monitoring the depth of the rotatable part, determining that the depth of the rotatable part has significantly changed, and taking a corrective action to return the depth of the rotatable part to said selected depth in order to prevent damage to an impeller that is liable to be caused by a change in depth of the rotatable part. The downhole pump further has a line shaft, an impeller engaged with the line shaft for pressurizing fluid to be extracted from a well, and monitoring apparatus for monitoring the depth of a distal end of the line shaft in order to prevent damage to the impeller that is liable to be caused by a change in depth of the distal end.

Abstract: A process for mineral oil production, in which an aqueous formulation comprising tris(2-hydroxyphenyl)methane of the general formula (I) is injected into a mineral oil deposit through an injection well and the crude oil is withdrawn from the deposit through a production well, where the R1, R2 and R radicals in the formula (I) are each defined as follows: R is independently 1 to 2 hydrocarbyl radicals per phenyl ring, R1 is preferably H or OH, R2 are independently radicals of the general formula (III), —(R5—O—)n—R6—X??(III) where n is a number from 1-50, and where the R5 radicals are R7 groups R6 is a single bond or an alkylene group having 1 to 10 carbon atoms, X is H or an acidic end group, R10 is, for example, C1-C6-hydrocarbyl radical, enables improved mineral oil production.

Abstract: An earth-boring drilling tool comprises a cutting element. The cutting element comprises a substrate, a diamond table, and at least one sensing element formed from a doped diamond material disposed at least partially within the diamond table. A method for determining an at-bit measurement for an earth-boring drill bit comprises receiving an electrical signal generated within a doped diamond material disposed within a diamond table of a cutting element of the earth-boring drill bit, and correlating the electrical signal with at least one parameter during a drilling operation.

Abstract: A monitoring tool, including an obstructor portion operatively arranged to impede fluid flow past the monitoring tool when the obstructor is engaged with a corresponding seat member. A disintegrable portion is included formed from a material operatively arranged to disintegrate upon exposure to a selected fluid. A gauge is coupled with the obstructor portion and the disintegrable portion. The gauge is operatively arranged to monitor one or more parameters and released from the obstructor portion when the disintegrable portion is disintegrated by the selected fluid. A method of monitoring one or more parameters is also included.

Abstract: Improved equipment and methods for determining the waiting-on-cement time after a cementing operation involve an optic-fiber coil that immersed in the cement slurry downhole. The intensity of a reflected light signal from the coil is monitored versus time. Attenuation of the reflected-light intensity corresponds to the development of gel strength, allowing operators to unambiguously determine when well-bore operations may recommence after a cement job. The optic-fiber coil is wound around a spool such that there is at least one coil crossing on the spool.

Abstract: According to an embodiment, a method of storing or transporting a sample comprises: inserting a sample container into a holding device, wherein the sample container contains the sample, wherein the sample container does not meet United States transportation regulations, wherein the holding device meets or exceeds United States transportation regulations, and wherein the holding device comprises a chamber and an opening; and storing or transporting the holding device. According to another embodiment, a holding device for containing a container comprises: a chamber; and an opening, wherein the holding device meets or exceeds United States transportation regulations, wherein the container contains a sample, and wherein United States regulations require the sample to be stored or transported according to the United States transportation regulations.

Abstract: An apparatus comprising a fluid communication device, a sample chamber, and a coupling assembly. The fluid communication device is operable to establish fluid communication between a downhole tool and a subterranean formation penetrated by a wellbore in which the downhole tool is positioned. The sample chamber is in selectable fluid communication with the formation via the fluid communication device. The coupling assembly mechanically couples the sample chamber within the downhole tool and comprises a cam rotatable between a first position and a second position, wherein the cam preloads the sample chamber when in the first position is disengaged from the sample chamber in the second position.

Abstract: A method for analyzing formation fluid in a subterranean formation is disclosed, wherein the method includes the steps of: adding a scavenger compound to an analytical reagent to form a reagent solution; collecting an amount of formation fluid into a formation tester, wherein the formation tester includes at least one fluids analyzer comprising at least one probe, at least one flow line, at least one reagent container, and at least one spectral analyzer, wherein the fluids analyzer is configured such that the collected formation fluid is fed through the at least one flow line to the at least one spectral analyzer; mixing an amount of the collected formation fluid with an amount of the reagent solution to form a mixture; and analyzing the mixture downhole.

Abstract: A device (1) for driving tunnels, galleries or the like including a cutting head (2), wherein an excavating direction of the cutting head (2) being essentially at a right angle to said rotation axis (R), a base unit (3) with stabilizing units (S1, S2, S3, S4) for applying and fixing against rock surfaces, a support unit (4) for the cutting head (2), a joint device (5) for pivotal connection of the support unit to the base unit, forcing means (6,7,8,9) arranged between the base unit and the support unit for swinging the cutting head. The joint device (5) is arranged for vertical as well as for horizontal swinging of the support unit (4) in respect of the base unit (3), wherein the support unit (4) is vertically as well as horizontally swingable by means of a pair of upper fluid cylinders (6,7) and a pair of lower fluid cylinders (8,9) comprising said forcing means.

Abstract: A dirt and rock cutting tool includes a cutting bit mounted on a bit holder. The cutting tool is secured to a bit holder in a manner that allows infinite rotational positioning of the cutting bit but substantially prevents rotation of the cutting bit once secured to a bit holder. The bit holder includes a planar shoulder and a shank extending from the planar shoulder. Shank has a terminal end which includes a threaded bore member. The bit holder includes a receiver dimensioned for receiving the shank. At least one hardened pin member is carried by the bit holder. At least a portion of the tip of the hardened pin extends beyond the surface of the shoulder. Upon securing the bit holder to the bit block, the hardened pin is pulled into the softer metal of the bit block, substantially preventing rotation of the bit holder within the bit block.

Abstract: The present invention relates to an interchangeable holder system comprising a basic module and an interchangeable holder for the accommodation of a cutting tool, which interchangeable holder is capable of being attached to the basic module, for the purpose of preparing ground surfaces, and to a construction machine, more particularly a stabilizer, a recycler, or a cold milling machine, comprising a milling device comprising such an interchangeable holder system.

Abstract: A method for removing the coating from a gas turbine component, namely for the complete or partial removal of a multilayer wear protection coating from the surface of the gas turbine component, the wear protection coating having at least one relatively hard ceramic layer and at least one relatively soft metallic layer, wherein, in order to remove the multilayer wear protection coating, the gas turbine component is alternately positioned in two different chemical baths, a first bath being used exclusively for the removal of each relatively hard ceramic layer, and a second bath being used exclusively for the removal of each relatively soft metallic layer of the wear protection coating.

Abstract: A gas turbine engine section comprises a rotatable shaft, first and second axially adjacent components, a nut, and a multifunction positioning lock washer. The first and second axially adjacent components are located on the rotatable shaft and are separated by an axial separation distance. The nut is configured to thread onto the rotatable shaft to hold one of the first and second axially adjacent components in compression. The multifunction positioning lock washer has antirotation geometry configured to prevent the nut from tightening or loosening. The axial length of the multifunction positioning lock washer is adjusted by removing material based on measurement of the axial separation distance to take in tolerances and reduce the axial separation distance.

Abstract: A gas turbine engine has a plurality of compressor rotors, as well as a plurality of turbine rotors. A tie shaft of the engine is constrained to rotate with the compressor and turbine rotors during normal operating conditions. Further, an upstream hub is in threaded engagement with the tie shaft. The threads of the upstream hub are handed in a first manner when viewed from an upstream location. A downstream abutment member is positioned downstream of the turbine rotors and is also in threaded engagement with the tie shaft. Threads of the downstream abutment member are handed in the first manner when viewed from a downstream location. Accordingly, the compressor and turbine sections of the engine are reliably held together, and the tie shaft is substantially prevented from unwinding.

Abstract: An airfoil array is disclosed. The airfoil array may include an endwall, and a plurality of airfoils radially projecting from the endwall. Each airfoil may have a first side and an opposite second side extending axially in chord between a leading edge and a trailing edge. The airfoil array may further include a convex profiled region extending from the endwall adjacent the first side of at least one of said plurality of airfoils and near the leading edge of the at least one of said plurality of airfoils. The airfoil array may further include a concave profiled region in the endwall adjacent the first side of said at least one of said plurality of airfoils and aft of the convex profiled region.

Abstract: A rotor in a gas turbine engine has a rotor body with at least one slot receiving a blade. The blade has an outer surface formed of a first material and an airfoil extending from a dovetail. The dovetail is received in the slot. A grounding element is in contact with a portion of the dovetail formed of a second material that is more electrically conductive than the first material. The grounding element is in contact with a rotating element that rotates with the rotor and is formed of a third material. The first material is less electrically conductive than the third material. The grounding element and rotating element together form a ground path from the portion of the dovetail into the rotor.

Abstract: A method of forming a component for use in a gas turbine engine includes the steps of forming an airfoil/root assembly; creating a platform assembly structure having an opening; inserting the airfoil/root assembly into the opening; and bonding the platform assembly structure to the airfoil/root assembly to form the component.

Abstract: A two-layered NiCoCrAlY layer is provided. The layer includes a bottom and a top layer. Through the use of a two-layered NiCoCrAlY layer, it is possible to reduce the formation of cracks in the thermally grown oxide layer as forms on account of the protective action of the NiCoCrAlY layers.

Abstract: An assembly for connecting a coverplate and a rotor includes a first rotor for use in a rotating engine; a first cover mounted to the first rotor, wherein the rotor and the cover create a space there between, the space for having cooling air therein; and a lock assembly for preventing the cover from rotating circumferentially or moving axially away from the rotor if mounted to the to the rotor wherein the cover is sealed against the rotor.

Abstract: The present application provides a turbine rotor and blade assembly for a steam turbine. The turbine rotor and blade assembly may include a rotor, a number of buckets positioned about the rotor, and a locking blade positioned about the rotor. The locking blade may include a multi-piece configuration.

Abstract: A turbomachine compressor or turbine including annular anti-wear shims mounted against hooks of a stator, each shim being substantially of channel-section defining an annular groove for engaging on a hook, the shim mounted against the downstream hook bearing axially via its middle annular wall on the stator, or on the casing, and one of its side walls includes a bearing device at its end remote from the middle annular wall for bearing against the casing or the stator, respectively, which bearing device is elastically deformable in an axial direction so as to urge the stator upstream.

Abstract: A retention system includes a structure clamp to connect the retention system to another structure; and a manifold clamp connected to the structure clamp, the manifold clamp including a trough to receive a pipe, a plurality of tube clamps with split cylinders extending through the trough, a collar to clamp around the pipe, and a spring to bias the trough from the collar.

Abstract: A fairing for a turbine engine strut includes: inner and outer bands; a vane extending between the bands; the fairing is split along a generally transverse plane passing through the bands and the vane, defining nose and tail pieces; wherein the vane is defined by spaced-apart sidewalls extending between a leading edge and a trailing edge, each sidewall split into forward and aft portions by the transverse plane; wherein each sidewall portion carries a radially-inwardly extending post, the posts positioned such that pairs of the posts lie adjacent to each other when the nose piece and tail piece are assembled, wherein each pair of adjacent posts includes at least two non-parallel faces; and a pair of slotted buckles, wherein each slotted buckle surrounds and clamps together a pair of the posts, wherein each pair of adjacent posts contacts a slot of the corresponding buckle in a tripod contact configuration.

Abstract: A gas duct for a gas turbine through which exhaust gases from the gas turbine are discharged to an outside includes a concentric inner casing and an outer casing disposed at a distance from the inner casing and concentrically encompassing the inner casing. A plurality of radial support struts interconnect the inner casing and the outer casing. Each of the support struts, the inner casing and the outer casing each have a heat-resistant lining disposed so as to provide protection against heat from the exhaust gases. The heat-resistant the linings of each of the support struts, the inner casing and the outer casing are divided in each case into a plurality of separate segments that are fastened to a support structure in an arrangement that provides an individual entirely or almost stress-free thermal expansion of each of the plurality of separate segments in an expansion plane.

Abstract: The invention relates to a control system for matching the output of a steam turbine (2) to a changed load, in particular for the short-term matching of the output of a power plant steam turbine (2) to changed network loads within the context of primary control. The control system according to the invention is characterized by a heat store (33) which, when there is an increased volume of steam tapped off from the steam turbine (2) under a correspondingly reduced load, extracts heat from the steam and which, when there is a reduced quantity of steam tapped off from the steam turbine under a correspondingly increased load, gives up heat to a steam/feed water circuit supplying the steam turbine (2).

Abstract: Certain embodiments of the invention may include systems, methods, and apparatus for determining online stress and life of a heat recovery steam generator. According to an example embodiment of the invention, a method for assessing components of a heat recovery steam generator (HRSG) is provided. The method includes receiving HRSG design parameters; monitoring thermal stress data from one or more temperature sensors in communication with one or more HRSG components; and determining cycle-related life consumption data associated with the one or more HRSG components based at least in part on the HRSG design parameters and the monitored thermal stress data.

Abstract: A finger lever is provided for a valve train of an internal combustion engine. The finger lever comprises an inner lever, at least one arm pivotally coupled to the inner lever, and a coupling device operatively displaceable to control movement of the at least one arm relative to the inner lever. The coupling device includes a slide and a piston disposed in a longitudinal bore of the inner lever, the piston having an entraining slot in which at least part of the slide is received, and at least one biasing member arranged to bias the piston relative to the inner lever. The slide is constructed to be displaced in a coupled position or an uncoupled position. In the coupled position the slide is entrained by the at least one arm, and in the uncoupled position the slide is not entrained by the at least one arm.

Abstract: A valve timing control apparatus includes a housing rotor, a vane rotor, a control valve, and a lock mechanism which locks a rotation phase at a stop time and a start time of an engine. The control valve has an atmospheric port communicating with atmosphere air; a discharge port through which hydraulic fluid is discharged from a discharge chamber communicating with the discharge port when the engine is stopped; and a check valve which intercepts the atmospheric port and the discharge port from each other by receiving a negative pressure from the discharge chamber through the discharge port when the engine is started.

Abstract: A sintered valve guide exhibits a metallic structure having a mixed structure and a hard phase in which hard particles are dispersed in an alloy matrix. The mixed structure consists of pearlite, an Fe—P—C ternary eutectic phase, a ferrite phase, a copper phase, and pores, and the mixed structure consists of, by mass %, 0.075 to 0.525% of P, 3.0 to 10.0% of Cu, 1.0 to 3.0% of C, and the balance of Fe and inevitable impurities. The hard phase is dispersed at 2 to 15 mass % in the mixed structure.

Abstract: An internal combustion engine (4) having an electrohydraulic valve control (1) for the variable lift drive of a gas exchange valve (3) is provided. The hydraulic valve (15) is actuated by an electronic control module (16) such that a gas exchange valve stroke (19) required for a charge change is adjusted during the cold start phase of the internal combustion engine (4) within a minimum stroke height (h-min) and a maximum closing time (?-max). A method for operating the internal combustion engine (4) is also provided.

Abstract: A valve operating system for an internal combustion engine, which includes a decompression cam member (47) that is supported on a camshaft (26) and that operates an exhaust valve operating member (29e) in an opening direction of an exhaust valve (17e) in a compression stroke when the engine is started, an exhaust gas recirculation cam member (48) that is supported on the camshaft (26) and that operates the exhaust valve operating member (29e) in the opening direction of the exhaust valve (17e) in an intake stroke when the engine is running at high speed, and a centrifugal mechanism (46) that is mounted on a driven timing rotating member (32) rotating integrally with the valve operating cam (25) and makes the decompression cam member (47) and the exhaust gas recirculation cam member (48) move, wherein the valve operating cam (25) is provided with a recess (39) surrounding the camshaft (26), the recess (39) opening on the face on the other side of the driven timing rotating member (32) and on a base face of the

Abstract: A gear device in which lubricating oil for cooling and lubricating gears to be driven therein is adjusted to a temperature and an amount suitable for the speed of a vehicle, and a vehicle having the gear device mounted thereon. A transmission adjusts the temperature of lubricating oil by supplying the lubricating oil from a lower part of a housing of the transmission into a heat exchanger by a circulation pump and causing the lubricating oil and engine cooling water to exchange heat with each other in the heat exchanger. A level of the lubricating oil retained in an oil pan when the circulation pump is stopped is defined as a highest oil level, while the level of the lubricating oil retained in the oil pan when the amount of the lubricating oil pumped up by the circulation pump is maximum is defined as a lowest oil level. The heat exchanger is disposed at a position outside the housing and higher than the highest oil level.

Abstract: A filter may include a cover defining a chamber and an annular filter element arranged within the chamber. The filter may also include a housing and at least one intermediate piece arranged between the cover and the housing when the cover is screwed to the housing. An inlet duct may be in communication with an untreated side of the filter element and an outlet duct may be in communication with a clean side of the filter element. A drainage duct may be arranged in the housing for draining the chamber during removal of the cover. A closure device may be arrange in the intermediate piece and have a closure element configured to close the drainage duct.

Abstract: A device 101 for reducing the acidity of motor oil for combustion engines, which device is part of the engine's lubrication system and contains monovalent cation exchanger 102, 202. It also relates to a method for regulating the acidity of motor oil whereby the oil is caused to pass through the acidity-regulating device. A vehicle is provided with the acidity-regulating device for motor oil.

Abstract: The present invention relates to an exhaust manifold for preventing condensate and gas leakage in an engine, and more particularly, to an exhaust manifold for preventing condensate and gas leakage in an engine, capable of preventing peripheries of the engine from being contaminated by condensate and/or exhaust gas leaking from interiors of a plurality of exhaust manifolds to the outside through connection portions of the exhaust manifolds.