A butterfly valve includes a purge gas flow path supplying a purge gas for preventing inflow of a control fluid into a magnetic fluid sealing portion from a flow path through an insertion hole. The purge gas flow path is provided with an opening and closing valve for opening and closing the purge gas flow path and a pressure gauge for measuring a pressure value in the purge gas flow path, in the stated order from the upstream side. The purge gas flow path is connected to a portion between the magnetic fluid sealing portion and the flow path of the butterfly valve on the downstream side of the pressure gauge, and communicates with the flow path through the insertion hole. The butterfly valve further includes a control device that controls at least the opening and closing valve. The control device is provided with a monitoring program for monitoring a pressure value.

A packing system is disclosed for use with a valve having a valve body that defines a flow passage therethrough. The packing system includes a bonnet configured for connection to the valve body, a stem bore extending through the bonnet to receive a stem of the valve that is movable within the stem bore to control flow through the flow passage, a first packing set arranged in the stem bore surrounding a first portion of the stem, a second packing set arranged in the stem bore surrounding a second portion of the stem that is spaced apart from the first packing set by a support ring to define an inter-packing volume within the stem bore, and a pressurized barrier lubricant reservoir in communication with the inter-packing volume via a bonnet port in the bonnet to pressurize barrier lubricant within the inter-packing volume to be at or above a process pressure.

A packing system is disclosed for use with a valve having a valve body that defines a flow passage therethrough. The packing system includes a bonnet configured for connection to the valve body, a stem bore extending through the bonnet to receive a stem of the valve that is movable within the stem bore to control flow through the flow passage, a first packing set arranged in the stem bore surrounding a first portion of the stem, a second packing set arranged in the stem bore surrounding a second portion of the stem that is spaced apart from the first packing set by a support ring to define an inter-packing volume within the stem bore, and a pressurized barrier lubricant reservoir in communication with the inter-packing volume via a bonnet port in the bonnet to pressurize barrier lubricant within the inter-packing volume to be at or above a process pressure.

Seal assemblies for use with fluid valves are described. An example apparatus includes a cage; a plug including a seal gland; and means for sealingly engaging an inner surface of the cage at least partially positioned in the seal gland and including a first portion and a second portion, in response to a fluid acting on the first portion in a first direction, the first portion to engage, outwardly urge, and splay the second portion to sealingly engage the cage, in response to the fluid acting in a second direction, the second portion to deter the fluid from acting on the first portion, the first direction opposite the second direction.

A packing system is disclosed for use with a valve having a valve body that defines a flow passage therethrough. The packing system includes a bonnet configured for connection to the valve body, a stem bore extending through the bonnet to receive a stem of the valve that is movable within the stem bore to control flow through the flow passage, a first packing set arranged in the stem bore surrounding a first portion of the stem, a second packing set arranged in the stem bore surrounding a second portion of the stem that is spaced apart from the first packing set by a support ring to define an inter-packing volume within the stem bore, and a pressurized barrier lubricant reservoir in communication with the inter-packing volume via a bonnet port in the bonnet to pressurize barrier lubricant within the inter-packing volume to be at or above a process pressure.

A gland repair tool is for repairing a gland seal in a high-pressure valve. The gland repair tool includes a tool body configured for attachment to an injection shutoff device fitted to a wall of the valve that is opposite the gland seal. A drill passage extends through the tool body and is configured to receive a drill bit for drilling a hole through the wall. A rotary seal creates a seal preventing the high-pressure medium from escaping the drill passage past the drill bit. A cooling circuit includes a cooling fluid inlet configured to convey a cooling fluid into the drill passage, a cooling fluid outlet configured to convey the cooling fluid out of the drill passage, and a one-way valve configured to prevent the cooling fluid from escaping the drill passage via the cooling fluid inlet. Corresponding assemblies and methods of operating the gland repair tool are provided.