Custom designed rotary sampling valve helps manufacturer of an oceanographic water sampler solve a difficult fluid transfer problem
Bio-Chem Valve/Omnifit has helped the manufacturer of an oceanographic water sampler solve a difficult fluid transfer problem by providing a custom-designed rotary sampling valve.
The client required a 50-way sampling valve with low torque, capable of operating to depths of 250 metres below the ocean surface.
The valve had to be resistant to exposure to seawater for periods of over three months at a time and operate over a wide range of temperatures and pressures.
As the overall design of the sampling instrument had already been finalised, the valve had to fit within a restricted space of 126mm diameter by 45mm height.
Omnifit experimented with several different approaches before presenting a design proposal to the customer.
Prototypes were manufactured for field testing, and once the final design was approved Omnifit set up a system at its manufacturing facility to meet the client's specific delivery requirements.
The solution was a two-tier valve designed to meet the space constraints of the instrument.
The rotor and body of the valve were manufactured from PVC, with the same coefficient of expansion to accommodate the wide variations in operating temperatures.
A novel sealing mechanism between the rotor and the body was developed utilising O-rings in the port and rotor to reduce the torque of the valve to below 4Nm.
Each of the ports has a bore of 1.5mm and is colour coded to make it easy to connect the correct tubing to the sampling bags.
Bio-Chem Valve/Omnifit specialises in the design and manufacturer of inert fluidic components for instrument manufacturers.
Its range of customised products includes bottle caps, manual and electric valves, fittings, tubing sets and chromatography columns.
