Abstract: A vacuum relief valve for a railroad tank car and methods for using the same to test the vacuum relief valve for leaks without requiring removal of the valve from the railroad tank car are described herein. According to one aspect of the invention, a vacuum relief valve described herein may be inspected for leaks without removing the vacuum relief valve from the railroad tank car by using two or more access openings located on the body of the vacuum relief valve. According to another aspect of the invention, a vacuum relief valve described herein may be inspected for leaks without removing the vacuum relief valve from the railroad tank car by using an opening to an interior cavity of the valve body that is revealed by rotating a cover from a closed position to an open position.

Abstract: A safety valve is outfit with sensors to monitor performance. The safety valve may include valve mechanics comprising a closure component moveable relative to a seat. The device may also have a pre-load unit coupled with the closure component. The pre-load unit may utilize a coiled compression spring to generate spring force to keep the closure component in contact with the seat. A strain gauge may be disposed on the compression spring to measure strain, for example, shear strain in the compression spring. Analysis of this data may predict set pressure (or “set point”). This prediction may, in turn, form a basis for an alert or other indicator that the safety valve requires maintenance or repair.

Abstract: A safety valve is outfit with sensors to monitor performance. The safety valve may include valve mechanics comprising a closure component moveable relative to a seat. The device may also have a pre-load unit coupled with the closure component. The pre-load unit may utilize a coiled compression spring to generate spring force to keep the closure component in contact with the seat. A strain gauge may be disposed on the compression spring to measure strain, for example, shear strain in the compression spring. Analysis of this data may predict set pressure (or “set point”). This prediction may, in turn, form a basis for an alert or other indicator that the safety valve requires maintenance or repair.

Abstract: Embodiments of a force generating element that can broaden the application of valves and, in particular, pilot-operated valves to include applications that have extreme operating temperatures. These improvements forgo use of o-rings (and like elastomeric devices) in lieu of more durable and robust seals (e.g., metal-to-metal contact). Rather, as discussed more below, the valves incorporate a force generating element that ensures contact between components to form appropriate seals that allow the cylinder to maintain pressure, despite dimensional changes in the structure of the valve.

Abstract: Techniques for monitoring operation of a relief valve containing an internal flow passage with a valve seat and valve plug disposed therein. The temperature of a fluid is sensed in the internal flow passage downstream of the seat. A valve temperature signal is generated representative of the temperature. The valve temperature signal is monitored to detect a rate of change in the temperature. The internal pressure of an inlet pressure line is sensed, connected to the internal flow passage upstream of the valve seat. A line pressure signal is generated representative of the internal pressure. The line pressure signal is compared against at least one expected line pressure value to determine a line pressure status. Operational status of the pressure relief valve is determined based at least in part on the detected rate of change of the fluid temperature and at least in part on the determined line pressure status.

Abstract: Embodiments of a force generating element that can broaden the application of valves and, in particular, pilot-operated valves to include applications that have extreme operating temperatures. These improvements forgo use of o-rings (and like elastomeric devices) in lieu of more durable and robust seals (e.g., metal-to-metal contact). Rather, as discussed more below, the valves incorporate a force generating element that ensures contact between components to form appropriate seals that allow the cylinder to maintain pressure, despite dimensional changes in the structure of the valve.

Abstract: Techniques for monitoring operation of a relief valve containing an internal flow passage with a valve seat and valve plug disposed therein. The temperature of a fluid is sensed in the internal flow passage downstream of the seat. A valve temperature signal is generated representative of the temperature. The valve temperature signal is monitored to detect a rate of change in the temperature. The internal pressure of an inlet pressure line is sensed, connected to the internal flow passage upstream of the valve seat. A line pressure signal is generated representative of the internal pressure. The line pressure signal is compared against at least one expected line pressure value to determine a line pressure status. Operational status of the pressure relief valve is determined based at least in part on the detected rate of change of the fluid temperature and at least in part on the determined line pressure status.

Abstract: Methods, systems, and programs for monitoring operation of one or more pressure relief valves, each relief valve containing an internal flow passage with a valve seat and valve plug disposed therein. The temperature of a fluid is sensed in the internal flow passage downstream of the valve seat. A valve temperature signal is generated representative of the temperature of the fluid downstream of the valve seat. The valve temperature signal is monitored to detect a rate of change in the temperature of the fluid downstream of the valve seat. The internal pressure of an inlet pressure line is sensed, connected to the internal flow passage upstream of the valve seat. A line pressure signal is generated representative of the internal pressure of the inlet pressure line. The line pressure signal is compared against at least one expected line pressure value to determine a line pressure status.

Abstract: Methods, systems, and programs for monitoring operation of one or more pressure relief valves, each relief valve containing an internal flow passage with a valve seat and valve plug disposed therein. The temperature of a fluid is sensed in the internal flow passage downstream of the valve seat. A valve temperature signal is generated representative of the temperature of the fluid downstream of the valve seat. The valve temperature signal is monitored to detect a rate of change in the temperature of the fluid downstream of the valve seat. The internal pressure of an inlet pressure line is sensed, connected to the internal flow passage upstream of the valve seat. A line pressure signal is generated representative of the internal pressure of the inlet pressure line. The line pressure signal is compared against at least one expected line pressure value to determine a line pressure status.

Abstract: An assembly and method for controlling the opening of a safety relief valve exposed to a system fluid pressure and containing a control fluid which controls the opening of the safety relief valve. The assembly includes a pilot valve connected to the safety relief valve and adapted to respond to a predetermined pressure of the system fluid for permitting flow of the control fluid. A regulator receives the control fluid and operates to reduce the pressure of the control fluid a predetermined amount. The safety relief valve opens in response to the reduction of the control fluid pressure, and the remaining control fluid pressure modulates the opening of the safety relief valve.