Best practices for fluid system maintenance and troubleshooting

Keeping valves and other fluid system components in peak working condition helps ensure efficient plant turnarounds

Fluid system insights

• There are several best practices to improve the installation and use of valves and other fluid system components within manufacturing facilities.
• Proper maintenance of fluid systems will reduce maintenance and improve overall operation of valves and similar components.

Facilities undergo turnarounds and shutdowns for any number of reasons. Plants may decide to perform maintenance, upgrade systems or renew existing systems. On occasion, facilities might decide to overhaul an entire plant at once. In any of these instances, teams should take time to plan and consider how to manage industrial fluid systems to minimize downtime and improve the facility’s overall performance.

Maintaining the critical components of a fluid system, including valves, regulators and other significant parts will make it easier to keep the turnaround running as efficiently and effectively as possible. While detailed and thorough plans allow technicians to troubleshoot components and keep them in peak working order, the key to good maintenance starts with how the system is installed.

Properly installing fluid system components

Poorly installed system components pose safety concerns for visitors, employees and the environment. Inadequate testing for proper pressurization can also have negative consequences for long-term system performance. Installation problems frequently result from undertrained technicians who lack full understanding of how fluid systems should operate.

Often when fluid system components fail prematurely, the cause can be linked to improper installation, especially of valves. Proper valve assembly within a system is critical to ongoing reliability. When installed correctly by properly trained technicians, valves and other components should require minimal ongoing maintenance over their life cycles.

Apply the following best practices to improve the installation of valves and other fluid system components within a plant:

• Plant operators have many options when it comes to choosing industrial fittings, valves, regulators and other fluid system components and choosing the right one for specific applications can feel like a nearly impossible task. Working with a reputable supplier to guide the process of selecting the exact components to fit the job can offer operators peace of mind.

• Identify the best material for individual components. This requires careful examination, as the ideal choice depends on what each component is carrying. For example, ensure components for a hydrogen system meet the necessary requirements to address the challenges of containing the very small molecules of this common process gas.

• After finalizing material and component selections, follow the manufacturer’s installation instructions carefully. Additionally, read the instruction manuals and take advantage of all supplier training. Before installation occurs, understand how to assemble and disassemble the systems, including proper tightening protocols. To help in this regard, technicians should use a gap inspection tool to guarantee fittings are tightened appropriately (see Figure 1).

• Train technicians extensively for maintenance activity, making use of all the opportunities and resources provided by trusted suppliers. The first step to a system’s smooth operation is recognizing problems early and fixing them efficiently.

• Do not ignore the operating parameters of a system when maintenance becomes necessary. For example, valves should never be installed to operate outside of their specified temperature and pressure ratings, where operating conditions could damage them.

• Provide maintenance technicians with ample space to complete their work. With the hands-on nature of maintenance and repair activity, ensuring easy accessibility is crucial (see Figure 2).

  

• Place valves and other components in areas where their performance and longevity will not be affected by unnecessary vibration. Technicians should deploy adequate supports for the tubing and piping to ensure they remain in place (see Figure 3).

• Check that all components allow fluids to flow in the same direction to prevent backups and leaks.

• Make sure all installations are secured and tight to eliminate costly and time-consuming leaks. A hydraulic fitting leaking six drops of fluid per minute, where each drop is 0.05 milliliters, adds up to half a liter per day, approximately 15 liters per month or approximately 180 liters per year. Assuming the cost of hydraulic fluid is $15 per gallon (or approximately $4/liter), this leak costs more than $700 per year in lost fluid.

  

• Keep contaminants away from your fluid system components by installing filters at critical points during the process. Filters will prevent particulates from interfering with the proper component operation. Specifically, contaminants can damage valve seats and otherwise prevent end products from matching end-user standards.

• Incorporate integrated gas panels within fluid systems to ensure easier accessibility for servicing. These panels feature front-facing primary components, making it significantly less difficult to change filters and perform other maintenance activities.

• Finally, make sure all fluid system components — especially valves — are safe. If a component is worn or damaged, take steps to determine whether it is repairable or should be replaced. Follow the manufacturer’s recommendations to help determine which actions are most appropriate. If there is any question, make sure to replace the valve to keep plant employees safe.

Thinking through these considerations thoroughly before putting a system into operation will help to make the system more reliable over its lifespan and require less maintenance to keep in proper working order.

Fixing fluid system component problems before they start

Establishing preventive maintenance schedules will keep components operating at peak performance throughout the overhaul. Further, regular maintenance will reduce unnecessary troubleshooting over the life of the system.

Industrial fluid systems are like fingerprints in that no two are exactly alike. Thus, the preventive maintenance schedule for one system may be radically different from the plan for another. Different factors could affect component longevity, including pressure, temperature, the fluid it carries and how many times it cycles on and off over time. It may be beneficial to consult the component supplier for its suggestions on any preventive maintenance guidelines.

In the case of overall component health, system parameters are less important. Preventive maintenance schedules should be designed to keep systems operating leak-free. Technicians may be able to detect leaks on their own by using their senses of sight and smell, but just because they do not notice anything concrete does not mean the system is free of leaks. To ensure a leak-tight system, technicians may have to deploy ultrasonic leak-detection equipment (see Figure 4) or liquid leak detectors (see Figure 5). It is important to catch leaks as early as possible to prevent them from becoming more dangerous over time.

Valves in industrial fluid systems may leak for various reasons, including because of unreliable metal-to-metal seals, system contaminants, poor installation and incorrect tubing choices. That’s why technicians should be familiar with best practices for detecting valve leaks and determining how to correct them:

Test the valve. Verify its operation and determine the nature of the leak. There are two main forms of valve leakage:

• A seat leak, where the leak is contained inside the valve, but fluid passes through the seal and the valve is unable to stop the flow.

• A shell leak, where fluid leaks outside of the valve into the atmosphere, often through the stem or body of the valve.

Inspect the valve. Examine all internal components, including the seats, O-rings and stem tips for wear or damage.

Repair the valve. Worn components like seats, packing and stems can often be replaced without the need to replace the valve entirely, based on the results of your inspection. In some instances, you may need to overhaul the valve, which involves replacing all internal wear components. Check with the valve supplier for available seal kits to make repairs.

Maintain the valve. Adjust your preventive maintenance or procedures once you gain a better understanding of how valve wear occurs in any given application. You can use tags to offer technicians quick, easy visual indicators of what individual valves do and how often they may need to be inspected.

Using tags to facilitate valve maintenance

Valves that feature tags with necessary technical information on them for reference make work much easier for technicians performing preventive maintenance.

Minimally, effective tags should have the part number, date of manufacture and trace identification order on them, allowing for easy ordering of new parts as necessary. Ideally, the tag would also contain information on the system media, operating pressures and temperatures. The type of tag used and the information included are unique to each situation and may be supplied by the component vendor.

Continued fluid system component operation

Components can frequently be repaired instead of replaced, but if the damage is significant enough, facility operators should not hesitate to replace them. Valves undergo significant stresses that may necessitate replacement instead of repair:

• Heavy corrosion may deteriorate the valve body, compromising its pressure-retaining capabilities and creating a safety risk.

• Major contamination that cannot be cleaned may ruin the valve’s performance.

• Overtightening a valve at its end connections can cause damage, rendering it unusable for reinstallation.

Though damage is the most common reason to replace a component, other reasons exist and should be considered. One factor is whether the cost of a new valve or other component, including the necessary installation labor, is within the budget. Another consideration is the potential downtime of taking a system out of production. In the case of a turnaround, that consideration may be less important than making sure the system is optimized.

A well-functioning industrial fluid system includes the proper components for an application, assembled carefully to ensure they operate leak free, efficiently and effectively throughout the plant. The more information technicians have about how to troubleshoot and maintain these components over time, the more efficient and profitable the plant may be.

This is especially true during the extensive work required for a turnaround, where the smallest mistake can cost thousands of dollars in delays and downtime. Working closely with an experienced component supplier who can guide the process will help ensure the industrial fluid system will remain operational during the plant’s transition.