461 results about "Leak rate" patented technology

A method of processing information in a tire pressure monitoring system includes the steps of: establishing a reference temperature; determining a pressure warning threshold at the reference temperature; measuring gauge pressure and gauge temperature within a tire cavity; correcting the gauge pressure to a filtered pressure value at the reference temperature using the Ideal Gas Law; and comparing the filtered pressure value against the pressure warning threshold to determine the necessity for a warning signal. In an advanced form of the invention, the method includes determining a pressure leak rate; predicting the time interval that the filtered pressure value will cross the pressure warning threshold at the leak rate and generating progressive warnings to the driver over the time interval. Fuzzy logic is used to quantify the probability of a warning state for each data point, allow for measurement error; and report the state of maximum probability to minimize the occurrence of false warning. A warning utility function is derived based upon a combination of the filtered pressure and leak rate.

A method and apparatus for testing a blowout preventer (BOP) wherein a pressurization unit applies fluid to an isolated portion of the throughbore of the BOP. A signal that is representative of the actual pressure in the isolated portion of the throughbore over successive time points and a pre-determined non-deterministic finite state automaton are used to predict the pressure in the isolated portion of the throughbore as a function of time relative to a pre-determined acceptable leak rate and the time at which stability is achieved. In one embodiment stability is achieved when successive predicted pressures are within a predetermined difference over a predetermined interval of time. Visual indications are provided to depict the progress of testing.

One or more components of a wellbore drilling assembly utilize a modular construction to facilitate assembly, disassembly, repair and/or maintenance of a wellbore drilling assembly and/or to extend the overall operating capabilities of the drilling assembly. In one embodiment, a modular construction is used for an APD Device, a motor driving the modular APD Device, a comminution device, and an annular seal. Individual modules can be configure have different operating set points, operating parameters and characteristics (e.g., rotational speeds, flow rates, pressure differentials, etc.) and/or different responses to given environmental factors or conditions (e.g., pressure, temperature, wellbore fluid chemistry, etc.). In one embodiment, the high-pressure seals used in conjunction with the APD Device and/or motor is a hydrodynamic seal that provides a selected leak or flow rates. Optionally, the seal is modular to provide different degrees of leak rates and/or different functional characteristics.

The invention discloses a device and a method for detecting the leak rate of an O type rubber sealing ring used for spaceflight, which belong to the technical field of the detection of spaceflight components. The device comprises gas storage equipment, an inflation valve, a first pre-pumping valve, a second pre-pumping valve, a leak detection tooling, a leak marking valve, a standard leak, a vacuum gauge, a deflation valve, a leak detection valve, a leak detector, a forestage angle valve, a prepump, a molecular pump, an ultrahigh vacuum gate valve and a vacuum booster pump. The method comprises the following steps of: firstly, pumping the pressure of a detection chamber and a dummy module below the air pressure of 10Pa, then pumping the detection chamber to a lower pressure by the molecular pump, forming a pressure difference between the detection chamber of the leak detection tooling and the dummy module and afterwards introducing high-purity gas with a standard atmosphere pressure into the dummy module. If a leak exists in a rubber sealing ring to be detected, the high-purity gas can enter the detection chamber by the sealing ring under the action of the pressure difference, and the leak rate of the sealing ring can be accurately calculated by the magnitude of the change of the output indication of the leak detector. The invention has the advantages of high detection sensitivity, high detection efficiency, reliable result and the like.

The invention discloses a metal-glass sealing process, which comprises the following steps: according to the expansion coefficient of a metal upper cover being greater than the expansion coefficient of glass and the expansion coefficient of the glass being less than or equal to the thermal expansion coefficient of a metal mandril, selecting sealing glass powder; pressurizing the selected glass powder into a glass blank by a mould, and dewaxing and forming the glass blank in a furnace; respectively putting a metal material and the glass blank into a deoiling solution for treatment, and washing and drying the metal material and the glass blank after the deoiling; and assembling the metal upper cover, the metal mandril and the formed glass blank in a graphite mould, and sintering the assembled graphite mould in a sintering furnace. The metal and glass products sealed by the metal-glass sealing process have good sealing strength, good leakproofness with the leak rate less than 10 <-10>m <3>. Pa/s, and good leakproofness at a high temperature, and can solve the problems of fluid leakage, poor consistency and the like of consumer products. The metal-glass sealing process has strong operability and good consistency of the prepared products, and meets the requirement of mass production.

A distributed flow control system and method for GPRS networks to control and regulate data flow between multiple sources and a single destination within a GPRS network. The present system and method ensures the departing traffic from all of the sources conforms to the peak and average rate requirements that have been set forth by the BSS/PCU. A leaky bucket flow control mechanism is used at each respective one of the multiple sources for controlling flow of data from each respective source to the single destination. A maximum bucket size of a leaky bucket and a bucket leak rate are defined for each leaky bucket flow control mechanism. A multiplier (L) is estimated and determined for each respective source based on recent data arrival behaviors of the multiple sources. When a frame of the data is sent from the respective source to the single destination, a number of bytes equal to the size of the transmitted frame times the multiplier L is added to the leaky bucket.

A test device for measuring chemical emissions to the atmosphere from a leaking component that includes a housing containing an air mover for drawing ambient air directly into the housing. The air mover is capable of operating at a high flow rate and a low flow rate. A detector for detecting the presence of a chemical emission is positioned within the housing as well as a calculator for measuring the concentration of the chemical emission. Air is drawn directly into a housing at a low flow rate in a survey mode and once a leak is detected air is drawn directly into the housing at a high flow rate in a quantification mode. During the quantification mode the calculator determines a leak rate from the leaking component or alternatively indicates that the calculated leak rate is unreliable.

The invention discloses a device for detecting the leak rate of a sealing ring. The device for detecting the leak rate of the sealing ring comprises a ring flange, a flange which is connected with the ring flange in a sealing way, and an inner sealing groove and an outer sealing groove which are arranged between the ring flange and a flange cover, wherein a sealing ring to be detected is arranged in the inner sealing groove, and a standard sealing ring is arranged in the outer sealing groove; an annular leak detection groove and a gas cavity are arranged at a contact part of the ring flange and the flange cover, and the annular leak detection groove is arranged between the outer sealing groove and the inner sealing groove and is communicated with an external leak detection pipe without leakage; and the gas cavity is arranged at the center of the flange and is communicated with a cylinder arranged outside the flange without leakage. The device has the advantages of compact structure, small volume, and convenience and quickness in heating, and the problem that the traditional detection device is difficultly applied to the detection of the leak rate of the sealing ring in high-pressure and high-temperature environments can be solved.

A density sensor for monitoring a rate of leakage from the case of electrical switchgear filled with dielectric gas under pressure, the sensor comprising a fixing support mounted from the outside in the thickness of the case and communicating with the dielectric gas. A radiator is placed around the fixing support of the density sensor, thereby enabling a measurement artifact that is due to the exposure of the case and of the sensor to solar radiation to be transformed in such a manner that any risk of untimely crossing of a low density threshold is eliminated.

The invention provides an atmosphere accumulation leak detection system which comprises a collector, a leak detector, an atmosphere reference gas source, a probe gas sampling system and a leak rate calibration system. The invention also provides an atmosphere accumulation leak detection method. The leak detection system and the leak detection method are suitable for the total leak rate detection of large-size workpieces of the aerospace industry, ships, vehicles, the nuclear industry, and the like, and meanwhile, the leak detection system and the leak detection method are also suitable for smaller workpieces having sealing requirements of other industries. The detection method belongs to the range of non-contact nondestructive detection, cannot do any damage to detected pieces and completely conforms to national relative standards of nondestructive detection.

PCT No. PCT/GB96/02571 Sec. 371 Date May 12, 1998 Sec. 102(e) Date May 12, 1998 PCT Filed Oct. 17, 1996 PCT Pub. No. WO97/14944 PCT Pub. Date Apr. 24, 1997A method and apparatus for testing a fluid conduit system for leaks. The apparatus is connected to an isolated section of a domestic fuel gas system which is suspected of leaking. The apparatus determines over recorded time periods the pressure drop in the system as a result of the actual gas leak and subsequently the pressure drop in the system as a result of an actual leak plus the leakage through an introduced artificial and calibrated orifice provided by the apparatus. The data is used in an equation for calculating the actual leakage rate from the system. This method avoids the need to repressurize the system between pressure drop measurements or having to know or assume the volume of the system being tested.

The invention discloses a method and a device for detecting cloth flaws based on adaptive orthogonal wavelet transform. Manual eye detection and an original automatic flaw detecting method in which wavelet transform is carried out after a wavelet basis is manually selected are replaced. The defects of traditional manual eye detection, such as low detection speed, low efficiency, false detection and high detection leaking rate are overcome. The problem of the original flaw detecting method based on wavelet transform that the detection precision is low as the wavelet basis is not optimized is solved. The optimal wavelet basis matched with a cloth texture is selected by an improved quantum rotating gate quantum genetic algorithm, the quantum rotating angle is regulated by a dynamic strategy, fine adaptive search is realized, the variety is enriched through introducing mutation operation, and the optimization capability of the algorithnm is improved through combining chaotic search. The flaw detecting method has the advantages of high speed, high accuracy, simplicity in operation and high efficiency and has great application prospects.

Methods and apparatus are provided for detecting leaks in a MEMS sensor package, and in particular, a MEMS sensor package that includes an oscillating structure or element that has a Quality (Q) value. The method and apparatus may include measuring the Q value of the MEMS sensor at a first time, applying a pressure to the outside of the MEMS sensor package, and measuring the Q value of the MEMS sensor at a second time after pressure has been applied for a period of time. A change in the measured Q values between the first time and the second time may be determined, which may then be correlated to a leak rate for the particular MEMS sensor package. In some cases, a leak rate of 2×10⁻¹³ He atm.cc/s or less may be detected.

A leak rate measuring method measures a leak rate of a vacuum apparatus including a vacuum chamber in which an object is accommodated to be processed, a first gas exhaust pump connected to the vacuum chamber via a first valve serving as a conductance variable valve, and a second valve connected to a downstream side of the first gas exhaust pump in a gas flowing direction. In the leak rate measuring method, there is provided a circulating path branched from a gas exhaust path between the first gas exhaust pump and the second valve and connected to the vacuum pump to communicate therewith. The pressure inside the vacuum chamber is monitored by circulating a gas into the vacuum chamber through the circulating path with first gas exhaust pump under the condition that the first valve is set at a predetermined conductance and the second valve is closed.

Disclosed herein are various implementations of systems and methods for improving the process and accuracy of converting acoustical signals to leak rates through a structure, such as a closed valve or coupling, using filtering techniques and modal analysis. These systems and methods may be useful for verifying the accuracy of the conventional approaches and inventive processes and systems for improving leak rate quantification using acoustic emissions. For example, a testing apparatus for simulating a leak through a structure and methods for correlating an acoustical signal with a leak rate are disclosed. The information gathered from the testing apparatus and/or correlation methods may be used in the field to determine more accurately the leak rate of a fluid or gas through the structure.

A fast acting and low leak rate vent for an impact landing bag in which a vent hole is covered by a gas barrier assembly having a flexible membrane and a low gas permeability layer. A flap assembly positioned around the gas barrier assembly includes flaps that are movable between an open position in which the membrane is exposed and a closed position in which the flaps cover and reinforce the gas barrier assembly. An externally actuated flow initiator is associated with a fastening element that retains the flaps in the closed position. Upon landing, the flow initiator is activated to sever the fastening element and release the flaps and the low gas permeability layer. Thereafter, the internal pressure within the landing bag under landing forces causes the membrane to burst, releasing a flow of gas from within the landing bag to attenuate impact.