An apparatus includes a sensor body and a sensor configured to measure differential pressure. The apparatus also includes first and second coplanar pressure inputs in or on the sensor body, where the pressure inputs are configured to provide multiple input pressures to the sensor. Each pressure input includes a barrier diaphragm configured to move in response to pressure and an overload diaphragm configured to limit movement of the barrier diaphragm. First and second fill fluid may be configured to convey the pressures from the barrier diaphragms of the pressure inputs to the sensor as first and second input pressures. Passages may be configured to transport the fill fluid between (i) gaps between the barrier diaphragms and the overload diaphragms of the pressure inputs and (ii) the sensor and gaps between the overload diaphragms and the sensor body.

An apparatus includes a sensor body, a sensor configured to measure differential pressure, and first and second pressure inputs in or on the sensor body. The pressure inputs are configured to provide multiple input pressures to the sensor. Each pressure input includes a barrier diaphragm configured to move in response to pressure and an overload diaphragm configured to limit movement of the barrier diaphragm. The overload diaphragm is also configured to exert a preload force against the sensor body. The overload diaphragm of each pressure input may include multiple convolutions. Bases of the convolutions may be configured to provide the preload force, and tops of the convolutions may be separated from the sensor body by gaps. Tops of the convolutions that are non-adjacent may be configured to provide the preload force, and tops of the convolutions between the non-adjacent convolutions may be separated from the sensor body by gaps.

An apparatus includes a header containing a sensor configured to measure pressure and a sensor body connected to the header, where the sensor body and the header form a pressure vessel configured to receive an input pressure. The header is connected to the sensor body such that the input pressure received on an inner surface of the header is substantially equal to the input pressure received on an outer surface of the header. A lowest connection point of the header to the sensor body may be located at or above a highest point at which the input pressure extends into the header. A lower portion of the header may be unconnected to the sensor body and extend into an interior volume of the sensor body. The header may include a vent configured to expose the sensor to atmospheric pressure or a lower-pressure input pressure.

An apparatus includes a sensor body and a sensor configured to measure pressure. The apparatus also includes at least one pressure input in or on the sensor body, where the at least one pressure input is configured to provide at least one input pressure to the sensor. The apparatus further includes multiple fluid passages configured to convey the at least one input pressure from the at least one pressure input to the sensor using a fill fluid. The multiple fluid passages are configured to both (i) transport the fill fluid and (ii) absorb thermal energy in a flame created by the sensor before the flame exits the sensor body. The fluid passages can include long and narrow straight passages, long and narrow curved or helical passages, and turns or bends. The fluid passages can have small cross-sections relative to their lengths.

A tool for inserting a flame arrestor assembly into a process control device having a first passageway of a first depth and a second passageway of a second depth different from the first depth. The tool includes a head portion having a first diameter, and a tip portion having a second diameter less than the first diameter. The tip portion has a first portion, a second portion, and a third portion, the first and second portions being separated by a first notch, and the second and third portions being separated by a second notch. The first notch is arranged to indicate when the flame arrestor assembly is fully inserted into the first passageway, and the second notch is arranged to indicate when the flame arrestor assembly is fully inserted into the second passageway.

The state of a flame in a gas turbine engine combustor is acoustically monitored using a dynamic pressure sensor within the combustor. A spectral pattern of a dynamic pressure sensor output signal from the sensor is compared with a characteristic frequency pattern that includes information about an acoustic pattern of the flame and information about acoustic signal canceling due to reflections within the combustor. The spectral pattern may also be compared with a characteristic frequency pattern including information about a flame-out condition in the combustor.

A pressure transducer comprises a process module having a cylindrical main part made of a first material, wherein a pressure-sensitive process diaphragm and an axially disposed through-hole are provided in the main part, and a measuring module having a cylindrical base which is manufactured from a second material that differs from the first material. The base has a pressure sensor and a pin-like-portion, wherein the pin-like portion-projects into the through-hole such that an end portion of the pin-like portion is flush with the end portion of the main part facing the medium. The end portion of the pin-like portion is connected to the end portion of the main part facing the medium, wherein the pin-like portion tapers in the direction of the end portion of the pin-like portion.

The state of a flame in a subject combustor of a gas turbine engine is acoustically monitored using a dynamic pressure sensor within the subject combustor and one or more additional sensors in nearby combustors. Dynamic pressure sensor output signals from the sensors are cross correlated to identify acoustic oscillations generated by a flame in the subject combustor and received by the sensors. The cross correlation may be constrained by a maximum time delay between correlated components of the signals, based on physical characteristics.

The flame status of a group of gas turbine combustors is acoustically monitored using dynamic pressure sensors within the combustor. Dynamic pressure sensor output signals are received from the sensors and processed to determine flame status. The signals are processed both by performing a correlation analysis within each combustor and by applying a wavelet-based flame detection algorithm to each output signal. A flame is determined to be present based on the correlation analysis and the wavelet-based flame detection algorithm. The wavelet-based flame detection algorithm is chosen based on whether the gas turbine combustors are in an ignition phase or a monitoring phase.

A system for mounting a differential pressure indication device for indicating a presence of a directional differential pressure between a first space and a second space separated from the first space by a barrier is provided. The system may include a base configured to be mounted against the barrier, where the base includes a receptacle configured to removably receive the pressure indication device. The system may include at least one mounting fastener configured to removably secure the differential pressure indication device within the receptacle. The system may include a pitch adjuster configured to secure the base to the barrier, where movement of the pitch adjuster is configured to adjust a spacing between a portion of the base and the barrier to adjust the orientation of the base with respect to pitch.