Oxygen Tank Pressure

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Oxygen Tank Pressure

For many reasons, patients that require additional oxygen use storage tanks with compressed oxygen to supplement their normal air intake.  The size and subsequent capacity of the tank may vary but the full pressure is typically about 2,000 psi and can go as high as 3,000 psi. With this pressure level in the tank, a regulator converts the supplied pressure to a lower, and much safer, level for the user. With newer aluminum and other materials instead of steel to avoid magnetism problems in situations such Magnetic resonance Imaging (MRI) tests, the pressure level is lower. Minimum pressure in tanks is around 300 psi with delivery systems operating at pressure below 400 psi. In contrast, the storage and delivery system of liquid oxygen in a hospital, pressures are usually around 50.0–55.1 psi. The amount of oxygen present inside the cylinder is measured by the pressure at the outlet nozzle.

PV/T = constant

where P is pressure in the cylinder,

V is the volume of the cylinder,

and T is the temperature

Applied Home Healthcare Equipment

Image courtesy of Applied Home Healthcare Equipment.

Normal clean air contains 19% to 21% oxygen. In contrast, a supply of 60% oxygen with 40% nitrogen is considered acceptable for most clinical purposes but usually high much higher content is available.

Portable oxygen cylinders often have flow and pressure gauges. They provide easy, on sight measurements for a user. However, remote monitoring can use microelectromechanical systems (MEMS) pressure sensors to provide an electrical signal that can be transmitted to one or more receivers.  With this information displayed remotely, a variety of healthcare givers can access and use the information.

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Safe Operating Pressures for Welding

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Safe Operating Pressures for Welding

Creating, cutting or repairing metal objects can involve welding. One type of welding uses an oxy-acetylene mixture of gases. Instead of air, pure oxygen is used to increase the temperature of the flame. The gases are stored separately in tanks and to monitor the gases, a pressure gage is installed on both the oxygen and the acetylene tanks. Before starting, each tank should read zero psi. To start the flame, the valve of the acetylene tank is rotated about a quarter of a turn to apply pressure to the regulator. Then the acetylene pressure is increased to 7 psi. Next, the oxygen gas valve is fully opened and then its regulator is adjusted to 40 psi. To start the flame, the acetylene valve on the torch is turned about ½ of a turn and an arc striker is used to ignite the acetylene. Then, the oxygen valve on the torch is opened to achieve a neutral flame or one without a hissing sound and where the flame goes from orange to blue. For safety, the acetylene is turned off at the torch and then the oxygen.  Similarly, at the tanks the acetylene is turned off first and then the oxygen. After purging the torch to make sure any gas residue is removed, the regulators are backed out and the final step is to check and make sure both tanks show zero pressure.

Acetylene tank welding torch

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Correct Pressures for Medical Procedures

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Correct Pressures for Medical Procedures

Gas control, medical control systems, air compressors and vacuum pumps are all possible equipment used in a medical or even a veterinary office. In all of these systems, monitoring and controlling the pressure is necessary to achieve the proper, efficient and safe values.

Patton's Medical gas control panel for nitrogenThe Patton’s Medical gas control panel for nitrogen clearly shows the supply (95 psi) and outlet (82 psi) pressures.

While gages are commonly used so medical personnel can easily observe the pressures during a procedure, microelectromechanical systems (MEMS) sensors could easily be installed behind the panel and then communicate the data to a local or remote monitoring station. With digital data, warnings can be implemented and archived data can be used to show that proper levels of critical elements, such as oxygen, were maintained during an operation.

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Pressure and Gas Chromatography

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Pressure and Gas Chromatography

Gas chromatography uses stationary and mobile phases for separating and analyzing mixtures according to “Chromatography Composition Measurement,” in The Measurement, Instrumentation, and Sensors Handbook. To perform the necessary steps, the typical gas chromatograph has several different aspects. It starts with a pressure regulated carrier gas supply. The carrier gas pressures are typically 34 to 69 kPa (5 to 10 psig) to 138 to 340 kPa (20 to 50 psig) at gas flow rates of 1 mL min-1 or less. If the data system monitors and records the supplied pressures, pressure sensors would also be used.

To measure this range of pressures, All Sensors SPM 401 Series of media isolated sensors would provide a good solution since process control and monitoring systems are target applications.

Gas Chromatograph

The components of a gas chromatograph include regulating gas pressure.  Source: http://faculty.uml.edu/david_ryan/84.314/Instrumental%20Lecture%2016.pdf

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