Liquid gases are used across a broad range of industries. Liquid nitrogen is used in cryogenics. Argon is used in welding. The semiconductor industry uses many different liquid gases in the production of silicon wafers. These include silicon tetrafluoride, silicon tetrachloride, silane, disilane, and dichlorosilane, to name just a few.
Weighing Liquified Gases In Cylinder Scales
Gases are stored in their liquid form in high-pressure cylinders. The cylinders allow for a much larger amount of gas to be stored than if it was in its gaseous form. For both safety and general production considerations, it is extremely important to monitor the level of liquid remaining in a tank.
When filling a chlorine cylinder, for example, monitoring the liquid level can prevent the danger of overfilling. During production, monitoring the rate of gas use is important to ensure that all products are being made properly. Damage caused to products due to excessive or interrupting gas flow can cost a company tens of thousands of dollars. In addition, it is very useful to know how much gas is remaining in each cylinder. With that, the supply does not run out at an inconvenient time.
There are two ways of measuring the amount of gas remaining in a cylinder. Gas pressure can be measured by using a pressure transducer. But pressure transducers are useless when using liquid gas. As long as there is liquid in the gas container, the pressure in the container will remain the same as gas is released from the cylinder and more gas evaporates from the liquid form. Only once all of the liquid has been depleted will the pressure quickly decline. The drop gives little warning to the operator that the cylinder has to be replaced.
A much more useful method of measuring liquid levels in cylinders is by using an electronic weigh scale. When a cylinder with liquid gas in it is placed on one of these industrial scales and the known weight of the cylinder itself is subtracted from the measured weight, the total amount of gas in the cylinder can be determined. The remaining liquid level in the cylinder can be constantly monitored.
A Setpoint Controller allows alerts to be programmed into the cylinder scale at several liquid levels to warn operators when a tank is nearing empty and has to be refilled or replaced. An analog 4 to 20 ma output signal is commonly used to communicate with other processing equipment. These electronic signals can be used to open and close valves.
Today, it is becoming more common to find a digital RS-232 signal, or a USB interface used with cylinder scales. In addition, the digital scale can be connected via Ethernet to a local access network, allowing monitoring of the cylinder liquid level from any computer on the network and even opening up the possibility of viewing liquid level data from the internet. Modbus provides easy interfacing with a PLC.
Due to the heavy weight of cylinders, it is important for a cylinder scale to have a low profile to allow for easy loading and unloading of the cylinders. Some manufactured scales, such as those by Arlyn Scales, produce high-quality weighing systems that are just over 1 inch in height. They do this by creating a pocket within the body of the scale to fit the rugged, abuse-resistant stainless steel load cell..
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Common Industrial & Commercial Uses For Cylinder Scales
Liquified gases have widespread use throughout the manufacturing world. But there are some gases that are specific to certain industrial processes.
Measuring the Weight of CO2
Liquid carbon dioxide is used for the carbonation of beverages, pneumatic systems, filling fire extinguishers, welding, production of plastics and rubbers, and pharmaceutical processing. The most common cylinder sizes range from 5 lb capacity 5 ¼” diameter up to a 516 lb 26” diameter. Arlyn’s Cylinder Scales are suitable for cylinders from 30 lb to 150 lbs, and up to 400 lb and 14” diameter. Weighing CO2 in larger cylinders and tanks employ platform scales and floor scales..
Liquid Nitrogen Weighing Scales
Often employed in cryogenic work, this material is also used for food preservation, the formation of ammonia, and fertilizers. Nitrogen dewars are available in many sizes with 3 to 50 liters being the most popular. Platform scales are often the best choice for weighing these dewars. They have platform sizes starting at about 18” x 18”, and up to 48” x 48”.
Chlorine Cylinder Scales
Chlorine is ubiquitous in industries such as water treatment, paper production, pharmaceuticals, and plastic processing. It is often stored in larger tanks and weighed on higher capacity floor scales.
Peruse High-Quality Cylinder Scales From Arlyn For Accurate Cylinder Weights
Your cylinder scale weighing problems can be met with Arlyn Scales solutions. Peruse multiple sizes and capacity choices, system communication options, and corrosion-resistant construction, along with one to five-year warranties. They will provide the best alternatives. Our technical team is ready for your call.