A noise suppression unit is provided and configured to reduce noise generated by gas flow, where the suppression unit includes a body including an inlet port and an outlet port, a central passage structure extending between a first end and a second end of the body, at least one layer of a first absorbing material on the central passage structure and at least one layer of a second absorbing material on the central passage structure, where the first absorbing material and the second absorbing material are different. Sound waves generated by gas flow through the suppression unit passes through the central passage structure and the at least one layer of the first absorbing material and the at least one layer of the second absorbing material to reduce the sound waves and thereby the noise generated by the gas flow.

Compact sound attenuation systems for fluid ducts are provided having one or more sound attenuation units that can be absorptive or reflective, depending on design. Each sound attenuation unit has one or more encircling Helmholtz resonators that fully encircle the duct in a lateral direction. Sound attenuation units can be coincident with the duct well and either interior or exterior to the duct, or in some instances can be partly interior and partly exterior to the duct. Sound attenuation systems can be tuned for maximum attenuation of a single resonance frequency, or can include multiple units of different frequencies for broadband attenuation.

Compact sound attenuation systems for fluid ducts are provided having one or more sound attenuation units that can be absorptive or reflective, depending on design. Each sound attenuation unit has one or more encircling Helmholtz resonators that fully encircle the duct in a lateral direction. Sound attenuation units can be coincident with the duct well and either interior or exterior to the duct, or in some instances can be partly interior and partly exterior to the duct. Sound attenuation systems can be tuned for maximum attenuation of a single resonance frequency, or can include multiple units of different frequencies for broadband attenuation.

A decoupling element for an exhaust system (1) of a combustion engine, with an elastic exhaust gas-conducting body (3), with at least one support ring (7) connected to the body (3) in a fixed manner, which encloses an axial end portion (8) of the body (3) on the outside in the circumferential direction (5), and with at least one flange (9), which is fastened to the support ring (7) by means of a weld seam (12), wherein the flange (9) comprises a connecting piece (13), which is inserted in the end portion (8) of the body (3) enclosed by the support ring (7), and wherein the weld seam (12) is configured circumferential on the outside and connects an axial face end (14) of the support ring (7) facing away from the body (3) to the outer circumference (15) of the connecting piece (13) of the flange (9).

Vibration absorption tubing and a manufacturing method thereof. The manufacturing method includes: a solder placement step including: placing solder at solder placement portions in an inner cavity of an adaptor; a pipe fitting step including: fitting a corrugated pipe and the adaptor respectively to adaptor matching portions at corresponding sides of the adaptor, to communicate an adaptor inner cavity with an inner cavity of the corrugated pipe and inner cavities of external connection tubing; and fixing or limiting positions of the corrugated pipe, the adaptor, and the external connection tubing to obtain a tubing assembly; and a component brazing step including: performing furnace brazing on the tubing assembly of the external connection tubing to obtain a main vibration absorption tubing. The vibration absorption tubing has favorable brazing consistency, enhancing connection reliability of components.

Vibration absorption tubing and a manufacturing method thereof. The manufacturing method includes: a solder placement step including: placing solder at solder placement portions in an inner cavity of an adaptor; a pipe fitting step including: fitting a corrugated pipe and the adaptor respectively to adaptor matching portions at corresponding sides of the adaptor, to communicate an adaptor inner cavity with an inner cavity of the corrugated pipe and inner cavities of external connection tubing; and fixing or limiting positions of the corrugated pipe, the adaptor, and the external connection tubing to obtain a tubing assembly; and a component brazing step including: performing furnace brazing on the tubing assembly of the external connection tubing to obtain a main vibration absorption tubing. The vibration absorption tubing has favorable brazing consistency, enhancing connection reliability of components.

A method is provided for actively compensating for pressure changes of a working fluid within a conduit. A first cavity is provided in fluid communication with the conduit. A second cavity is in fluid communication with a control fluid. A plunger is in communication with both the first cavity and the second cavity and is movable in response to pressure changes of the working fluid in the conduit. The plunger is re-centered. Re-centering the plunger includes the following steps. Position data representative of movement of the plunger is collected. The position data is analyzed with a control unit to determine an average position of the plunger which is offset relative to a center position. The average position of the plunger is compared, with a control unit, to the center position. A signal is relayed from the control unit to a control valve to urge the plunger toward the center position.

A pipe connecting assembly includes a valve body, a valve stem and a fitting pipe part. The valve body includes a first valve body part and a second valve body part. The valve body has a valve cavity. The first valve body part has a first cavity, and the second valve body part has a second cavity. The valve stem is at least partially located in the valve cavity. The valve body is provided with a valve port. The valve stem can move in the valve cavity to close or open the valve port, so that the first cavity is separated from or in communication with the second cavity. The pipe connecting assembly further includes an adhesive layer located between the fitting pipe part and the first valve body part. Such a structure is beneficial to improving the connection reliability of the pipe connecting assembly.

A pipe connecting assembly includes a valve body, a valve stem and a fitting pipe part. The valve body includes a first valve body part and a second valve body part. The valve body has a valve cavity. The first valve body part has a first cavity, and the second valve body part has a second cavity. The valve stem is at least partially located in the valve cavity. The valve body is provided with a valve port. The valve stem can move in the valve cavity to close or open the valve port, so that the first cavity is separated from or in communication with the second cavity. The pipe connecting assembly further includes an adhesive layer located between the fitting pipe part and the first valve body part. Such a structure is beneficial to improving the connection reliability of the pipe connecting assembly.

A helical strake pole system that includes a tubular pole having a longitudinal axis and threaded attachment points. The system further includes a helical strake fin disposed circumferentially around a portion of the tubular pole along the longitudinal axis. The system further includes couplers disposed on the tubular pole. The couplers are configured such that each coupler has a first portion with a slot configured to receive an upper portion of the helical strake fin and a second portion configured to removably coupled to a threaded attachment point of the tubular pole. In addition, each coupler is configured to position a portion of the helical strake fin substantially perpendicular to a surface of the tubular pole.