Maintenance and repair of hydraulic systems

Hydraulic systems have many benefits, but leaks and plenty of maintenance requirements stop many businesses from using them for their applications. Luckily, proper hydraulic maintenance can prevent most of your problems, including leaks, as well as maximize hydraulic system uptime. After all, hydraulic maintenance requirements are not that complicated if you have a detailed preventive maintenance program on hand. In this article, learn about hydraulic fluid maintenance, preventive maintenance task lists, and how to measure the success of your hydraulic maintenance program.

Most Important Questions to Ask Yourself Before You Start

Now before we dive in any further into the hydraulic maintenance best practices, start from asking yourself a few simple questions:

1. What is my hydraulic system workload?
2. Is my hydraulic system operating at maximum flow and pressure higher than 70%?
3. What are the system operating conditions? Is my equipment located in a relatively hot and dirty environment?
4. What are the equipment manufacturers’ requirements when it comes to preventive maintenance for each piece of hydraulic equipment?
5. What are the requirements of hydraulic system components’ manufacturers when it comes to hydraulic fluid contamination and ISO particulate?
6. What are the requirements of filter manufacturers?
7. Is the previous maintenance history available? If yes, what is the history?

Three Types of Hydraulic Maintenance Explained

There are three main types of hydraulic maintenance: reactive maintenance (RM), preventive maintenance (PM) and predictive maintenance (PdM).

Reactive maintenance stands for breakdown maintenance and involves the repairs that are done to fix the equipment that is already broken.

Preventive maintenance is regular maintenance that is performed on the equipment to prevent it from breaking down. Preventive Maintenance is implemented through a Preventive Maintenance Program.

Predictive Maintenance or condition-based maintenance uses sensor devices to collect information about the system and components and prompts the personnel to perform maintenance at the exact moment when it’s needed. Due to high costs and technical requirements, it is still new to the market and not used very often.

Preventive Maintenance Program

The Preventive Maintenance Program is defined by the operating conditions and manufacturer requirements for each individual component and for the system as a whole. To start, you should write down or update the procedures for each preventive maintenance tasks. We recommend having a written copy of the Preventive Maintenance Program even if you own a small business and do not have a maintenance technician on staff. It is vital that all maintenance employees know, understand, and follow the maintenance procedures explicitly created for your business.

Hydraulic Fluid Maintenance Best Practices

Since the hydraulic system uses hydraulic fluid to power hydraulic machinery, you should pay extra attention to hydraulic fluid maintenance and care. Hydraulic fluid performs many functions, including minimizing wear and tear, reducing friction, removing heat, protecting the system from rust and deposits, removing debris, and dirt from the system.

The most common problems that cause hydraulic fluid going bad are system overheating, system contamination, and dirty operating environment. Therefore, to take care of the hydraulic fluid, you should take the following actions:

1. Prevent the hydraulic system from overheating. Hydraulic fluid gets hot while being pushed through the pumps, tubing, and relief valves. If the system’s temperature is too low, the condensation starts in the reservoir, which can cause pump cavitation. On the contrary, if the temperature is too high, oxidation that causes varnish and sludge deposits occurs. Most hydraulic systems run in the 110-150°F range with mobile hydraulic systems running up to 250°F. If you use a water-based hydraulic fluid, don’t let the temperature go below 140°F, so the water does not evaporate from the fluid. Perform regular checks of the oil cooler and outside the reservoir to prevent overheating.
2. Keep the System Clean. Prevent contamination of the system by dirt, water, metal debris from entering the system by keeping the reservoir cover, drain lines, and breather fill openings always clean.
3. Keep the Fluid Clean. Test oil regularly for contaminants. Store hydraulic fluid in the designated containers in the clean environment, clean the fill cap before adding hydraulic fluid. Change and check fluid filters on a regular basis. Filter oil added to the system through portable filters to achieve better results.