An emission module for treating exhaust gas including a housing, a first catalyst substrate positioned within the housing and having an inlet end, the first catalyst substrate defining a plurality of flow passages extending longitudinally from the inlet end, and a first restrictor plate positioned at the inlet end of the first catalyst substrate to block exhaust flow through a first portion of the plurality of flow passages while allowing exhaust flow through the remainder of the plurality of flow passages.

A snap-action valve assembly for an exhaust system is provided with a conduit that defines an exhaust passageway. A valve flap is disposed within the exhaust passageway for controlling exhaust flow. A shaft supports the valve flap in the exhaust passageway and allows the valve flap to rotate between closed and open positions. A mass damper, positioned outside the conduit, includes a longitudinal segment that is rotatably coupled to the shaft and that extends between first and second coiled ends. The longitudinal segment includes an inboard side and an outboard side. The first and second coiled ends include a series of overlapping layers arranged in either a folded serpentine shape or a spiral shape.

A damper valve assembly includes a valve housing, a valve flap and a torsional spring. The valve housing is adapted to be attached to a pipe of an exhaust system and defines an opening. The valve flap is rotatably coupled to the valve housing about a pivot axis. The valve flap is movable between a first position whereat fluid flow through the opening of the valve housing is restricted and a second position whereat fluid flow through the opening of the valve housing is allowed. The torsional spring engages the valve flap to bias the valve flap toward the first position. A preload of the torsional spring when the valve flap is in the first position is adjustable.

A damper valve assembly for an exhaust system of a vehicle includes a valve housing and a valve flap. The valve housing is adapted to be attached to a pipe of the exhaust system and defines an opening. The valve flap is rotatable relative to the valve housing and about a pivot axis between a first position whereat fluid flow through the opening of the valve housing is restricted and a second position whereat fluid flow through the opening of the valve housing is allowed. The valve flap includes a body and a mass damper. The mass damper is integral with the body and includes a plurality of segments that are folded so that the plurality of segments are in a stacked arrangement.

A damper valve assembly for an exhaust system of a vehicle includes a valve housing and a valve flap. The valve housing is adapted to be attached to a pipe of the exhaust system and defines an opening. The valve flap is rotatable relative to the valve housing and about a pivot axis between a first position whereat fluid flow through the opening of the valve housing is restricted and a second position whereat fluid flow through the opening of the valve housing is allowed. The valve flap includes a body and a mass damper. The mass damper is integral with the body and includes a plurality of segments that are folded so that the plurality of segments are in a stacked arrangement.

An exhaust manifold comprises a plurality of exhaust intake conduits structured to be fluidly coupled to an engine and receive exhaust gas from a corresponding cylinder of the engine. At least one exhaust intake conduit provides a reduction in an exhaust intake conduit cross-sectional area from an inlet to an outlet. A plurality of bends are each defined by a respective one of the exhaust intake conduit outlets. An exhaust intake manifold is fluidly coupled to the exhaust intake manifold and defines an exhaust intake manifold flow axis. Each of the plurality of bends is shaped so as to define n angle of approach of exhaust gas flowing therethrough. A first angle of approach of the first bend relative to the exhaust intake manifold flow axis is smaller than a second angle of approach of an inner second bend.

An exhaust component comprises a main casing and at least one partial casing pressed against the main casing. In a developed state, the partial casing has an elongated shape along a longitudinal line and is defined along a transverse direction, substantially perpendicular to the longitudinal line, by two side edges opposite one another. The partial casing has a given developed longitudinal length. The partial casing has no fastening to the main casing on at least one longitudinal segment, and the longitudinal segment extends from one side edge to the other and extends in total over a cumulative developed longitudinal length of at least 20% of the given developed longitudinal length.

An exhaust manifold comprises a plurality of exhaust intake conduits structured to be fluidly coupled to an engine and receive exhaust gas from a corresponding cylinder of the engine. At least one exhaust intake conduit provides a reduction in an exhaust intake conduit cross-sectional area from an inlet to an outlet. A plurality of bends are each defined by a respective one of the exhaust intake conduit outlets. An exhaust intake manifold is fluidly coupled to the exhaust intake manifold and defines an exhaust intake manifold flow axis. Each of the plurality of bends is shaped so as to define an angle of approach of exhaust gas flowing therethrough. A first angle of approach of the first bend relative to the exhaust intake manifold flow axis is smaller than a second angle of approach of an inner second bend.

An aftertreatment system includes: a selective catalytic reduction system including at least one catalyst for decomposing constituents of an exhaust gas produced by an engine, the exhaust gas having a pressure pulsation frequency; an exhaust conduit fluidly coupled to the selective catalytic reduction system and structured to deliver the exhaust gas to the selective catalytic reduction system from the engine; at least one mixer positioned in the exhaust conduit; and a reductant insertion assembly fluidly coupled to the exhaust conduit and structured to insert a reductant into the exhaust conduit upstream of the at least one mixer. The at least one mixer is structured to have a natural frequency matching the pressure pulsation frequency so as to cause resonant vibration in the at least one mixer, the resonant vibration causing reductant deposits to be removed from the at least one mixer.

A conduit connection assembly includes a first conduit part and a second conduit part, assembled to form a conduit connection delimiting a first fluid conducting volume from a second fluid conducting volume. The first and second fluid conducting volumes communicate with each other via a pressure change inducing device. During use of the conduit connection assembly, the pressure in the first conducting volume is higher than the pressure in the second conducting volume. A cavity is formed between the first and second conduit parts at a distance from the first fluid conducting volume, and a draining connection is adapted to provide a communication between the cavity and the second fluid conducting volume. A slot, formed by the assembly of the two conduit parts, provides a communication between the first fluid conducting volume and the cavity.