Abstract:
Described is a coupling seal that includes a polymeric body having a bore extending from a first end to an internal sealing surface and a fluid channel extending from the internal sealing surface to a second end. The bore is configured to receive a tube having a fluid channel so that an endface of the tube engages the internal sealing surface. The second end of the polymeric body is configured to contact a sealing surface of a coupling body that has a fluid channel extending from the sealing surface. A fluidic seal occurs when the coupling seal is compressed between the endface and the sealing surface. A void between an outer surface of the polymeric body and an inner surface of the coupling body receives the deformation of the coupling seal while under compression to thereby prevent the fluid channel of the tube from being crushed or obstructed.
Abstract:
Described are a method and system for diluting a sample in a liquid chromatography system. A sample flowing at a first flow rate is combined for a predetermined time with a diluent flowing at a second flow rate to generate a volume of diluted sample. The diluted sample has a dilution ratio determined according to the two flow rates. A portion of the volume is loaded into a sample loop of an injection valve and subsequently injected into a mobile phase flowing to a chromatography column. The method eliminates the need to have a technician available to perform dilutions or to transfer the sample to a remote location for dilution. Advantageously, manufacturing or processing downtime to perform the dilution is not required and the amount of sample flowing to waste is reduced.
Abstract:
A check valve comprises a valve seat element along a fluid path that is formed of a polymeric material and comprises a hole that extends from an input end of the valve seat element to an output end of the valve seat element. The valve seat element includes an inner taper that transitions the input end to the output end, the valve seat element including a sealing surface along the inner taper. A poppet body is formed of a polymeric material and configured to engage the internal tapered sealing surface of the valve seat element. The poppet body moves between a first position at which the poppet body sealingly engages the tapered sealing surface of the valve seat element and a second position at which the poppet body is separate from the inner taper of the valve seat member.
Abstract:
Described is a mobile phase fitting having reduced corrosion and erosion. The fitting includes a coupling body, compression screw, compression member and gasket. The coupling body has a threaded bore at one end, a tapered cavity, a narrow bore and a fluid channel. The compression screw has an axial bore to receive a tube and a threaded outer surface in engagement with the threaded bore of the coupling body. The compression member is disposed in the tapered cavity and has an axial opening to pass the tube and a tapered surface to engage a surface of the tapered cavity. The gasket is disposed in the narrow bore and has one surface in contact with the first internal surface and has a parallel surface to receive an end face of the tube. Mobile phase flows along a path that includes the tube, an opening in the gasket and the fluid channel.