An abradable seal includes an outer ring arrangement and an energiser for urging said outer ring arrangement against an opposing surface, wherein an outermost surface of said outer ring arrangement defines a sealing surface of said abradable seal; wherein said outer ring arrangement is configured such that after a first period of operation said sealing surface suddenly transitions from having a relatively large surface area to having a relatively small surface area, so as to cause a sudden increase in internal leakage across the seal at said transition.

The present application provides a gas density relay with sealing performance self-checking function and an implementation method therefor. The gas density relay includes a gas density relay body, a sealing performance detector and an intelligent control unit; the sealing performance detector is communicated with a gas path of the gas density relay body or a sealed cavity in the gas density relay body to obtain gas leakage information of the gas density relay body; the intelligent control unit is connected with the sealing performance detector, receives and/or calculates the data and/or information monitored by the sealing performance detector, and performs diagnosis to obtain the current sealing performance of the gas density relay body; or, the intelligent control unit uploads the received data and/or information to a background, and the background performs diagnosis to obtain the current sealing performance of the gas density relay body. The gas density relay is used to monitor the gas density of gas insulated or arc extinguishing electrical equipment, and the gas leakage performance of the gas density relay can also be monitored on line, which reduces operation and maintenance costs and ensures safe operation of a power grid.

Device for testing sealing of at least a part of a double-door sealed transfer system between two closed volumes, the system including a first flange and a and a second flange capable of being rigidly connected to one another, and a first door and a second door normally sealing openings respectively defined by the first and the second flanges, the device including a casing including a cavity provided with an opening, mechanical connection to a flange so that the cavity is closed by the flange and the door and an inflatable joint which, in the inflated state, is in contact with the flange and ensures a sealing allowing to verify the sealing between the flange and the door.

An actuator system includes a piston-cylinder arrangement including a piston that is movable with respect to a cylinder. A first flow path is in fluid communication with the piston-cylinder arrangement and a second flow path is in fluid communication with the piston-cylinder arrangement. A control system is operable to fluidly connect the first flow path to a source of high-pressure fluid and to connect the second flow path to a drain to move the piston in a first direction. A pressure sensor is fluidly connected to the first flow path and is operable to measure sufficient pressure data during the movement of the piston to generate a pressure versus time curve. The control system is operable to compare the generated pressure versus time curve to a known standard pressure versus time curve stored in the control system to determine the condition of the piston-cylinder arrangement.

An actuator system includes a piston-cylinder arrangement including a piston that is movable with respect to a cylinder. A first flow path is in fluid communication with the piston-cylinder arrangement and a second flow path is in fluid communication with the piston-cylinder arrangement. A control system is operable to fluidly connect the first flow path to a source of high-pressure fluid and to connect the second flow path to a drain to move the piston in a first direction. A pressure sensor is fluidly connected to the first flow path and is operable to measure sufficient pressure data during the movement of the piston to generate a pressure versus time curve. The control system is operable to compare the generated pressure versus time curve to a known standard pressure versus time curve stored in the control system to determine the condition of the piston-cylinder arrangement.

The present disclosure relates to techniques for detecting leaks in a pump. A compressed fluid, such as compressed CO.sub.2, is provided through a first channel formed within a pump head. The compressed fluid within the first channel is in contact with at least a portion of a pump piston, and the first channel is substantially sealed using a fluid seal positioned around a portion of the pump piston. A wash fluid is pumped into a second channel formed within a wash seal housing associated with the pump head using a fluid pump. The wash fluid within the second channel surrounds a portion of the pump piston and is separated from the first channel by the fluid seal. A flow rate of fluid exiting the wash seal housing via the second channel is measured, and the existence of a leak is determined based on the measured flow rate.

A multi-seal sealing assembly with sensors includes a housing, a first sensor and a second sensor. The housing can receive multiple seals and can mount to a surface of a tool. The multiple seals are configured to seal against fluid flow between the surface of the tool and the housing. Multiple sensors corresponding to the multiple seals are mounted to the housing adjacent respective seals and between the housing and the surface of the tool. The sensors sense a flow parameter at different levels responsive to an absence or a presence of fluid flow past the seals.

A method is provided for testing an annular seal within a gas turbine engine. During this method, a vacuum is applied to a first volume through a conduit. The annular seal is between the first volume and a second volume. A vacuum pressure is measured within the conduit while the vacuum is applied. The measured vacuum pressure is compared to a threshold vacuum pressure. A difference between the measured vacuum pressure and the threshold vacuum pressure is indicative of leakage across the annular seal from the second volume to the first volume.

A pressure-adjustable auxiliary control system for high-pressure gas sealing detection includes: a high-pressure chamber environment monitoring unit configured to construct high-pressure test gas sealing environment and to test sealing performance of a sealing member; a first gas pipeline divided into two branches, of which one branch is connected to the high-pressure chamber environment monitoring unit as a first gas replacement path; a second gas pipeline which is connected to a test gas pressurization path together with the other branch of the first gas pipeline, where a first booster pump processing unit and a second booster pump processing unit are sequentially arranged in the test gas pressurization path for pressurizing the test gas, and are connected to the high-pressure chamber environment monitoring unit; a system air control module configured for control of respective air control valves; and a booster pump air control module and a driving air source preprocessing unit.

The method for testing the integrity of a seal of a cavity in an engine includes providing a sealed test tank external to the cavity, the test tank having an internal volume that is particularly selected, as described herein. A pressure differential is generated between the test tank and the cavity, by creating an initial test pressure within the test tank that is different than an ambient pressure inside the cavity. Gas flow between the test tank and the cavity is then permitted, and a change in pressure within the test tank is measured, as is a test time required for the pressure inside the test tank to reach a reference pressure. The measured test time is compared with a predetermined reference time, and the integrity of the seal may be confirmed when the test time is greater than or equal to the reference time.