Which pressure gauges should be digital
The pressure gauge is probably one of the most important instruments in the factory tool belt. They are essential for safety and process reliability. However, their importance seems to be underestimated or even ignored.
A major manufacturer of analog pressure gauges found that in any given factory, 25 percent of pressure gauges were damaged, and another 40 percent required immediate corrective action.
This amazing statistic reflects two problems. First of all, we did not take the pressure gauge as seriously as it should be. Secondly, the analog pressure gauge is too easy to break.
Therefore, with this in mind, we want to discuss which damaged analog pressure gauges should be replaced with more accurate and durable digital pressure gauges.
We have proposed 3 basic categories that require digital pressure gauges:
During calibration and testing
Improve visibility and control
Ensure durability in harsh environments
Calibration and testing
During calibration and testing, accuracy has never been more important. Although a typical analog pressure gauge may provide moderate accuracy—the error range is only 1 percent —a digital pressure gauge can greatly improve accuracy. It is easy to find a digital meter with an error band of only 0.1 percent . That's 10 times better!
Here are some examples of our customers:
Infusion pump alarm calibration
An infusion pump usually injects fluid into your circulatory system by intravenous injection. You can also think of it as an IV pump. Their reliable operation is vital to the safety of patients and the responsibility of medical institutions.
The pump has a critical alarm called the "downstream obstruction alarm". When the IV tube is blocked, this alarm will notify the doctor and nurse. Alarms are based on pressure. When the pressure on the discharge side of the pump increases, an alarm will sound.
To make the alarm meet the specifications, use a pressure gauge to set the alarm. However, the accuracy must be 0.1 percent to ensure proper performance. Therefore, a digital pressure gauge is a must.
In fact, many infusion pumps are calibrated with our PG5, which has a pressure range of 30.0 psig and an error range of only ±0.03 psig, which is 0.1 percent of full scale.
Brake leak detection
In order to accurately detect leaks in the braking system, the sensor must be able to detect small changes in pressure over a relatively large range. This only applies to digital pressure gauges and requires very high resolution{{0}}resolutions of 0.01 and 0.001 are very common.
A famous motorcycle manufacturer uses our digital pressure gauge to monitor their brake lines. They are looking for pressure changes as low as 0.023 psi on a 20.00 psi gauge.
No need to explain
Regardless of the application, in fact, any reference meter-what you call a meter used to test, calibrate or monitor other important equipment-should be a digital pressure gauge.
When accuracy is imminent, it's hard to believe anything else. The digital pressure gauge can tell you exactly what the pressure is at any given point in time, without guessing the numbers or pointer positions. No need to explain.
Improve visibility and control
The visibility is lowest on analog meters. Checking for pressure requires the use of a clipboard, walking, climbing, or dodging to get to wherever the pressure gauge is. And control basically does not exist. Analog instruments are strictly used for monitoring.
On the other hand, digital meters can help you increase visibility and control. They are easier to read, eliminate guesswork about precise needle positions, can be read from a distance, and can provide output integrated with your SCADA system. Some even have basically independently controlled trip points for valves, pumps or alarms.
Sending a signal to SCADA allows you to modernize measurements at key locations while maintaining a local display for field operators. You no longer have to choose between a pressure gauge and a transmitter.
Here are some examples of our customers' increased visibility and control:
Vehicle and equipment lifts
We have some OEM customers using our digital meters as the display of their lifting equipment. This task was once done with analog meters, but digital meters are better.
The main reason is better visibility. Not only is the digital display easier to read, but our meter can also convert psi to almost anything else-such as weight.
One example comes from Tinker Air Force Base, where they use B-52 bombers. When the aging B-52 was shut down for maintenance, the crew used up to 38 jacks to lift the aircraft off the ground. They use our 4.5-inch diameter PG10 high-visibility digital pressure gauge on each jack to ensure even weight distribution.
Maintaining an even distribution of weight is essential to protect the old fuselage from structural damage. The B-52 has been discontinued since 1962, but through upgrades and careful maintenance, the existing fleet is expected to be in service until 2045.
Using a very accurate and very visible digital pressure gauge, maintenance personnel can carefully lift the aircraft for maintenance without shortening its life expectancy.
Pump control
Experienced pump consultants like the world-renowned Larry Bachus will tell you that proper pump control requires a pressure gauge. Although accuracy is less important for pump control, visibility and control are critical.
The advantage of digital pressure gauges is that the outputs and trip points they provide can be used to signal and issue an alarm to the SCADA system or shut down the pump. They also convert psi to head to help the operator compare the measurement with the pump curve.
Recently, a sugar factory in Central America invested in some PG7s for pump monitoring and control, and achieved great success. When the vibration increases, the digital format makes it easier to read the meter-this is common in any processing plant.
We even provide pressure gauges with cables between the sensor and the display, so you can remove the electronics from vibrations, heat, or the chaos of process connection points.
Digital pressure gauges provide many advantages for pump control, especially in hard-to-reach places, dirty environments, or high vibrations.
Consider the launcher
A good rule of thumb is that whenever you consider replacing an old analog meter with a transmitter, use a digital meter. The digital pressure gauge with output will provide the same benefits as the transmitter, plus the local display of the meter, the cost is about the same.
Whether in the control room or on the factory floor, you can use one device to solve visibility and control issues.
Durability in harsh environments
Our analog instrument counterparts have found that many instruments are in various states of disrepair. The problem may be a lack of understanding of how to use the meter correctly; it may be layoffs; or it may simply be a matter of instrument durability.
Of course, each factory's situation may be different. However, digital pressure gauges can help solve at least two of these potential causes.
It makes sense to replace analog instruments in harsh environments with digital instruments. There are no moving parts, and with better overpressure tolerance, the numbers are inherently more durable. This means that a leaner workforce can make it easier for them to serve.
Perhaps more importantly, the digital instrument does not have a long Bourdon tube that can block.
Filter monitoring
A good example of one of our customers is filter monitoring. Pressure gauges are usually used to monitor filters, whether for differential pressure measurement or to monitor the increase in upstream or suction pressure.
A customer monitors the upstream pressure in a tissue manufacturing plant. These filters remove pulp from waste ink used in the printing process. The filter will quickly become clogged, and if it is not replaced quickly, downstream equipment may be damaged.
The Bourdon tube is easily soiled by so much pulp in the ink, and the digital gauge is unaffected-no diaphragm seal is required. In addition, when the filter needs to be replaced, the meter will send a signal to the HMI control system to notify the personnel.
When should your meter be digital
Bottom line: When you need the accuracy, better visibility, control, or durability of a pressure gauge, use a digital pressure gauge. Doing so will reduce the number of disrepaired meters and improve the overall safety and reliability of the plant.
There are several options to dedicate your digital meter to your specific application. Contact us to learn more about how digital pressure gauges can provide you with better measurements.
