Industrial Pressure Gauges with Acid Leak Detection Technology

In the chemical manufacturing and processing world, the instrumentation and tools used in the industry need to be of the highest quality and withstand harsh operating conditions. These instruments, which are often directly exposed to chemical processes, must endure exposure to extreme temperatures, corrosive substances, and other aggressive conditions. One of the vital instruments in the chemical industry is the industrial pressure gauge, a device used to measure and monitor the pressure of fluids and gases in pipelines, vessels, and other industrial systems. Given the significance of accurate pressure measurement, integrating acid leak detection (ALD) technology into these pressure gauges has become increasingly important. Acid leak detection assemblies offer a valuable tool for industry professionals, providing a visual indication of changes in process media, as they utilize a special coating that changes color when exposed to compounds with pH levels of ≤3.0.

Need for Acid Leak Detection in Pressure Gauges

Industrial pressure gauges are vital for monitoring and controlling processes in various industries, particularly the chemical industry, where accurate pressure readings ensure product quality, safety, and compliance with regulations. As many chemical processes involve acidic substances, a leak of corrosive acids can have serious consequences. Not only can it damage equipment and result in costly downtime, but it can also pose serious safety risks to workers and the environment.

Acid leak detection technology plays an essential role in mitigating these risks. By incorporating this technology into industrial pressure gauges, it is possible to quickly detect leaks of acidic compounds and take appropriate action to prevent damage and ensure safety.

How ALD Technology Works in Pressure Gauges

The ALD technology is a special coating applied to parts of the pressure gauge that might come in contact with the process media in the event of a leak. This coating changes color when exposed to compounds with pH levels of ≤3.0, making it an effective tool for detecting acidic leaks.

The color change in the coating is usually irreversible, which allows for easy identification of leaks even after the fact. Once the gauge shows evidence of a color change, it indicates that an acid leak has occurred, and maintenance personnel can take appropriate measures to address the issue.

Pressure gauges equipped with ALD technology are installed in critical areas of chemical plants, refineries, and other industrial facilities with a high potential for acid leaks. 

They monitor pressure in pipelines, tanks, reactors, and other equipment where corrosive substances are processed or stored.

Advantages of ALD Technology in Pressure Gauges

• Early Detection: ALD technology allows for the early detection of acid leaks, preventing further damage to equipment and reducing the risk of accidents.
• Visual Indication: The color change clearly indicates a leak, making it easier for operators to identify the issue and take corrective action.
• Enhanced Safety: By detecting leaks early, ALD technology helps to improve the safety of workers and the environment.
• Cost Savings: Early detection of acid leaks can reduce downtime and repair costs, leading to cost savings for the facility.

Conclusion

Incorporating acid leak detection technology into industrial pressure gauges is an effective way to enhance the safety and efficiency of chemical processes. The ALD technology visually indicates changes in process media, helping operators quickly identify and address leaks of acidic compounds. This technology not only improves the facility's overall safety but also reduces the risk of costly equipment damage and downtime.

Mead O'Brien

https://meadobrien.com

(800) 874-9655

Understanding Differential Pressure Measurement: Differential Pressure Gauge Example

This video (courtesy of Ashcroft) does an outstanding job illustrating the concepts of differential pressure and flow measurement using the differential pressure method.

Engineered restriction devices are often inserted into a closed pipe system to create a differential pressure for the purposes of measuring fluid flow rate. These restrictions can come in the form of an orifice plates, Venturi, wedge, and other designs.

To measure the differential pressure, taps must be installed on both sides of the plate.  The upstream side will always produce the greater pressure, and is referred to as the high side. Conversely, the downstream pressure will always be the lesser value, due to the obstruction.

A differential pressure gauge's range is based on the maximum difference that can be expected as a result of the restriction. The gauge's dial will display the differential pressure in units of pressure measurement, like psi or bar.  By applying the linear square root relationship between flow rate and pressure, the gauge style can be scaled in a specified rate of flow, such as gallons per minute. A dual scale dial can also be created to display both the flow rate and the differential pressure.

Another important consideration is the maximum line pressure, also referred to as the static pressure. The higher the static pressure, the more robust the gauge must be to contain it. That's why it's crucial to ensure that the gauge carries a static pressure rating that exceeds the highest pressure in the line.

For more information about differential pressure gauges, transmitters, and flow measurement, contact Mead O'Brien at (800) 892-2769 or visit their web site at https://meadobrien.com.

Five Important Criteria in Applying Pressure Gauges

Process pressure gauge.
(Ashcroft)

Pressure gauges are installed in countless industrial and commercial applications around the world. From hygienic pharmaceutical process lines, to the most unpleasant and hostile areas in chemical, power, and food processing plants.

While there are millions of possible combinations of shapes, sizes, options and materials, pressure gauges all share the five  following application criteria, required for safe use and long product life.

Diaphragm seal.
(Ashcroft)

1 - Process Media Properties: Media that is corrosive, sludgy, or that can solidify is a potential problem for pressure gauges. In non-corrosive, non-clogging media applications, a direct connection without intermediate protection can be applied. For process media that could potentially clog or chemically affect the gauge's wetted parts, a diaphragm seal should be used.

2 - Process Media Temperature: Very hot media, such as steam or hot water, can elevate the gauge's internal temperature leading to failure or an unsafe condition. For high temperature applications, the use of a "pigtail siphon" or diaphragm seal is recommended. Siphons act as a heat sink and lower the exposure temperature. Diaphragm seals isolate the gauge from the higher temperatures.

Pigtail siphon.

3 - Ambient Operating Temperature and Environment: It is important to know the ambient environmental rating for any process instrument. Elevated ambient temperatures, moisture, vibration, and corrosive atmospheres can all affect accuracy, calibration, and safety. Choose the proper housing and mechanism materials if oxidizing or reducing atmospheres exist, and consider the addition of ancillary devices, such as remote diaphragm seals to physically relocate the gauge away from the hostile area.

Snubber

4 - Severe Pressure Fluctuations: In applications where dramatic line pulsations or strong over-pressure conditions are a possibility, the use of pressure restrictors, snubbers, or liquid-filled gauges will extend the service life of the pressure gauge.

5 - Mounting: Pressure gauges are standardly available with bottom (radial) and back connections. NPT (National Pipe Thread Taper) threaded connections are generally the standard. Many other process connections are available though, such as straight threads, metric threads, and specialized fittings. Make sure you know how the gauge is being connected. When mounting, pressure gauges should be almost always be mounted upright.

For more information about pressure gauges, contact Mead O'Brien by visiting https://meadobrien.com or by calling (800) 892-2769.

Ashcroft Materials Compatibility and Corrosion Guide

Ashcroft products.

Below is a very good materials compatibility and corrosion guide courtesy of Ashcroft.

The reference is intended to serve solely as a general guide in the recommendation of materials for corrosive services and must be regarded as indicative only and not as any guarantee for a specific service.  There are many conditions which cannot be covered by a simple tabulation such as this, which is based on uncontaminated chemicals, not mixtures.

Many of the chemicals listed are dangerous or toxic.  No material recommendation should be made when there is insufficient information, a high degree of risk, or an extremely dangerous chemical.  The end user is responsible for testing materials in his own application, or for securing the services of a qualified engineer to recommend materials.

The end user is responsible for the choice of product(s) in his own application, based upon his own determination of the materials, chemical, and corrosion factors involved. THIS GUIDE AND ITS CONTENT ARE PROVIDED ON AN “AS IS" BASIS WITHOUT WARRANTY OF ANY KIND.

You can refer to the embedded document below, or you can download your Ashcroft Corrosion Guide PDF from this link.

Ashcroft Corrosion Guide from Mead O'Brien, Inc.

Dampening the Effects of Vibration on Industrial Pressure Gauges

Vibration must be considered
when applying pressure gauges.

Pressure gauges rely on precise and responsive mechanisms to display changes in system pressure as rotational needle movement. By their very nature, these mechanisms are responsive to pulsations within the pressurized system and vibrations that may be evident in the connected piping and structures. The effect of vibration and pulsation is seen as an indicating pointer oscillating rapidly, making a definitive or even useful reading impossible. One solution, applied traditionally, was to fill the gauge with a viscous liquid that would dampen the rapid oscillation of the indicating needle.

While a liquid filled gauge does solve the oscillation problem, it does have a drawback. The liquid in the gauge presents its own set of operational issues requiring consideration in any application.

Provision should be made to check and maintain the liquid level in the gauge
A liquid filled gauge is an additional source of potential leakage in a facility

Ashcroft, a globally recognized manufacturer of gauges for commercial, industrial, and laboratory use, offers a different solution that provides the deflection dampening of a liquid gauge without liquid fill. Available on many of their gauges, the "Plus" option enables stable gauge face display in a dry gauge.

The video below provides a side by side demonstration of a liquid filled and a Plus gauge, so you can see the performance of both types. Share your process gauge requirements and challenges with instrumentation experts, combining your process knowledge with their product application expertise to develop effective solutions.