Waters Investments Limited

Waters Technologies Corporation

Waters Technologies Ireland Limited

Robert J Dumas

Steven J Ciavarini

Joseph A Luongo

Kurt D Joudrey

Kenneth R Plant

Gary W Bertone

Taylor J Castagna

Joshua A Shreve

Sylvain Gilles Cormier

William W Carson

Wade P Leveille

Michael R Jackson

Frank Rubino

Aaron Lebeau

Edwin H Denecke

Ryan M Hill

Richard Victor

David Lamborghini

Richard Earle

Robert Tacconi

Robert E Reynolds

Jeffrey Howard Stokes

John Carneiro

Frank A Rubino

Robert Q Tacconi

Disclosed is a pressure transducer including a body made of a material having a first coefficient of thermal expansion, a fluidic inlet and a fluidic cavity enclosed by the body in fluidic communication with the fluidic inlet. The pressure transducer further includes a strain gauge including a resistive element in operable contact with the body. At least a portion of the resistive element made of a material having a second coefficient of thermal expansion that is different from the first coefficient of thermal expansion of the body. Disclosed further is a pressure transducer including a filler body located in a fluidic cavity of the pressure transducer configured to reduce adiabatic thermal effects on a transducer body. Disclosed are systems and methods incorporating the pressure transducers described herein.

Adiabatic reducing pressure transducer, system and method

Techniques and apparatus for diagnostic processes for analytical instruments are described. In one embodiment, for example, an apparatus may include at least one memory, and logic coupled to the at least one memory. The logic may be configured to receive diagnostic information associated with at least one analytical instrument, and process the diagnostic information using a computational model to generate at least one diagnostic model for at least one diagnostic. Other embodiments are described.

Techniques for analytical instrument performance diagnostics

Adiabatic thermal pulse compensating pressure transducer and method

Systems and methods for pumping carbon dioxide in a chromatography system include an actuator that receives and compresses carbon dioxide at or above room temperature at a given pressure to put the carbon dioxide in or near supercritical form. This actuator can be a pre-pump disposed on the intake side of a pumping system. Alternatively, this actuator can be a primary actuator in the pumping system. The actuator includes an intake chamber that receives the carbon dioxide and a movable plunger extending into and closely received by the intake chamber. The plunger has a diameter and stroke length adapted to compress the carbon dioxide received by the intake chamber in sufficient volume at the given pressure to put the carbon dioxide in or near supercritical form at or above room temperature. A metered amount of the carbon dioxide in or near supercritical form can then be pumped.

Carbon dioxide liquid phase forming using high volume head displacement

The present disclosure relates to phase detection in multi-phase fluids where two fluid phases can be present in the fluid. Phase detection apparatus and methods are disclosed for determining the phase(s) (e.g., supercritical, liquid, and/or gas) of a fluid in a multi-phase fluid system, such as carbon dioxide based separation and chromatography system.

Phase detection in multi-phase fluids

Embodiments of the present invention feature a method and apparatus for detecting defects, such as, leaks, component failure and adverse performance. One embodiment of the present apparatus for pumping fluid comprises a pumping chamber having an inlet and an outlet powered by a motor. The motor operates in pumping mode upon receiving a pumping signal. The apparatus further comprises at least one inlet valve in fluid communication with the inlet of the pumping chamber. And, the apparatus comprises a switchable valve in fluid communication with the outlet of the pumping chamber. The switchable valve has a closed position and an open position, and assumes the closed position upon receiving a close signal. A pressure measuring device is in fluid communication with the pumping chamber, between said inlet valve and switchable valve. The pressure measuring device determines a minimal pressure and first threshold pressure at a first time and a second threshold pressure at a second time. The control means calculates the slope of a line representing the difference of said first threshold pressure signal and said second threshold pressure signal over time and comparing the slope with a threshold decay value. And, the control means compares the minimal pressure to a minimal acceptable value. Deviations from such values represent a defect in the pump.

Methods and apparatus for determining the presence or absence of a fluid leak

A thermal exchanger for a liquid chromatography system is provided. The tube-in-tube thermal exchanger comprises a first and a second sections of tubing, a first connector and a second connector. The first section of tubing carries sample solution from the packed chromatography column. The second tubing carries the sample solution from the detector out of the system, i.e., in an opposite direction to the direction of the first section of tubing. Both the first section of tubing and the second section of tubing connect to the first connector, which combines the two sections of tubing into a thermal exchange tubing. The thermal exchange tubing comprises the first section of tubing placed inside the second section of tubing such that waste fluid from the second tubing can optimally exchange thermal energy with fluid from the chromatography column. The thermal exchange tubing is configured into a plurality of coils. The number of coils in the thermal exchange tubing is specific to the chromatography application and is determined by various parameters including the composition of the sample solution, estimated temperature gradient, fluid flow rates and heat transfer coefficient. The thermal exchanger provides stabilized temperature fluid to a detector with minimal volume into the flow path between the chromatography column and the detector.

Tube-in-tube thermal exchanger for liquid chromatography systems

A serial, dual piston high pressure fluid pumping system that overcomes the difficulties of gas in the fluid stream without the need for added mechanical valves or fluid paths. A bubble detection and recovery mechanism monitors compression and decompression volumes of the serially configured dual pump head pump, and the overall system delivery pressure. Bubble detection is effected by sensing a ratio of compression to decompression volume and determining if the ratio exceeds an empirical threshold that suggests the ratio of gas-to-liquid content of eluent or fluid in the system is beyond the pump's ability to accurately meter a solvent mixture. The magnitude of the ratio of compression to decompression volume indicates that either the intake stroke has a bubble or that the eluent has a higher-than-normal, gas content. Once a bubble has been detected, recovery is effected by forcing the pump into a very high stroke volume to achieve a high compression ratio to expel a bubble, and automatically apportioning an optimal amount of piston travel necessary to keep gases compressed into the solution and maintain steady flow.

Bubble detection and recovery in a liquid pumping system

A serial, dual piston high pressure fluid pumping system that overcomes the difficulties of gas in the fluid stream without the need for added mechanical valves or fluid paths. A bubble detection and recovery mechanism monitors compression and decompression volumes of the serially configured dual pump head pump, and the overall system delivery pressure. Bubble detection is effected by sensing a ratio of compression to decompression volume and determining if the ratio exceeds an empirical threshold that suggests the ratio of gas-to-liquid content of eluent or fluid in the system is beyond the pump's ability to accurately meter a solvent mixture. The magnitude of the ratio of compression to decompression volume indicates that either the intake stroke has a bubble or that the eluent has a higher-than-normal gas content. Once a bubble has been detected, recovery is effected by forcing the pump into a very high stroke volume with the compression and decompression stroke limits constrained to obtain the largest delivery stroke compression ratio that will expel a bubble or solvent that has detrimental quantities of gas.

An improved gradient proportioning valve compensates for hydraulic inertia in a compact, reliably sealed valve assembly that is less susceptible to unswept volumes and gas permeation. A flat diaphragm is located within an accumulator volume integral to a valve manifold block. The compliance and damping of the diaphragm are optimized for the application's flow characteristics. Sealing of the diaphragm is provided by a sealing plug installed in the manifold block. The diaphragm has only one sealing joint. The sealing plug configuration allows for a more reliable clamping and sealing of the diaphragm which reduces and substantially eliminates the potential for leaks. Potential for unswept volumes is substantially eliminated by including the accumulator volume as a unitary part of the valve manifold. Air permeation into the fluid stream is substantially reduced by a reduction in surface area and exposed liquid volume in the accumulator, effected by including the accumulator volume as part of the valve manifold. Valve size is decreased by the elimination of the external tube accumulators and associate fittings. The valve that is more conducive to use and attainment of the benefits of in-line solvent degassing. More accurate delivery of the respective proportions of components of a liquid composition is achieved. Pump flow is positively impacted.

Gradient proportioning valve

A pump configured so that tools are not required to remove the pump head and disassemble the plunger. A single large hand operated knob or head nut facilitates tool-less pump head removal. The pump head is guided into position in a manifold and held in place by the hand knob. The manifold is designed to receive all the external fluidic connections made to the pump head. Fluid paths to the pump head have been replaced with miniature face seals which facilitate high pressure sealing between the pump head and manifold. Low pressure tubing seals reside in a seal wash chamber or housing and are not attached to the head, eliminating the need for tooling to disconnect them during pump head removal. A tool-less plunger mechanism includes a nutcap assembly having a plunger socket receiving a plunger assembly including a sapphire plunger fixed to a plunger holder ball accommodated by the socket. The plunger assembly is captured within the socket by a plurality of cams. The cams are spring loaded to rotate and collapse onto the plunger holder ball, pulling the plunger assembly tightly into the socket. A restricting cone is actuated to rotate the cams away from the plunger holder ball for release and removal of the plunger assembly.

Growing community of inventors

Upton, MA, United States of America

Robert J Dumas