Managing a baler’s lifeblood

Jun 01, 2023

Businesses can live and die on the efficiency of their balers. It’s often considered a recycling facility’s workhorse and can be subjected to strenuous conditions. This is why operators should treat their balers as if they are the most important part of the human body—the heart.

“The baler’s hydraulics are the lifeblood of the machine,” says Glenn Godwin, director of Engineering at Harris, headquartered in Cordele, Georgia. “Every time you extend and retract a hydraulic cylinder, you're potentially ingesting contamination from outside into the hydraulic system. This creates issues with both the short-term and long-term performance of the baler.”

Maintaining the hydraulic system begins with maintaining the fluid that’s pumped through it. Eric Farmer, director of Parts and Service at Harris, says the hydraulic fluid is the blood in the system because it flows through all the components that move the machine, and the most common issues are direct results of contamination in the hydraulic system.

External contamination in the fluid is the primary way hydraulic systems can fail. Dust, debris and dirt can get in from the outside at different points, such as the system’s breathers in the tank or by settling on the cylinder rods as they move, Godwin says. The machine also can be at risk if the tank is exposed by leaving the lid on the top of the reservoir open, for example. If a worker opens the lid on the reservoir or forgets to put a seal back in or to bolt it down, dust and debris will be pulled into the hydraulic system.

In addition to external contamination, internal components break down and wear over time, creating contamination within the system.

Farmer says this contamination, if left unchecked, causes premature wear on the system and eventually leads to failures. Dirty oil can cause valves to not function properly and not direct oil flow properly, and a failure such as a stuck relief valve could over pressurize the system causing issues like pump failures and cylinder failures.

“Being a major component of the equipment, if a main cylinder fails, a crane will be required to remove it, and then it will have to be shipped back to the manufacturer and rebuilt,” Farmer says.

Godwin adds that primary indicators of system failure include slower and/or erratic performance. Another indication of a cylinder issue is a change in bale weight. If bales have been averaging 1,500 pounds, for example, and begin to weigh less when baling the same material, the cylinder could be beginning to fail.

Balers typically have analog gauges and human machine interface (HMI) that monitor the system’s hydraulic pressure. Godwin says if an operator is in the process of bailing and the system pressure cannot be achieved, that is another clear indicator of an issue with the hydraulic system.

While balers are workhorses, Farmer says treating them as such isn’t always a good thing. Operators who overfeed the baler run the risk of increased issues, longer downtime and more expensive fixes. Properly feeding the baler is a balancing act that needs to be considered to ensure the machine runs efficiently without failure.

Another important thing to consider is the environment the machine is being used in. Farmer says problems in a hydraulic system most frequently are caused by a lack of cleanliness from poor housekeeping practices. It is important to clean the oil cooler, keeping the top of the tank clean to help with the ingress of dirt. Operators also should clean around the cylinders, removing any material because they can build up behind a ram and contribute to the system’s contamination.

The cost of replacing or fixing the hydraulic system depends on what is broken. Farmer says a valve could take 30 minutes to replace and cost a couple hundred dollars, but replacing a cylinder potentially could take more than a day because it could require renting a crane to remove it. If the operator wants that cylinder rebuilt, the baler could be down as long as two weeks. As far as cost, Farmer says a replacement cylinder or rebuilding the existing one could be thousands of dollars.

“You’ve got to do preventative maintenance,” Farmer says. “We have daily, weekly, monthly, semiannual and annual maintenance schedules for our machines. It should be followed very close to get the most out of your machine.”

Operators should check the condition of the hydraulic oil every 250 hours of operation. Evaluating the results of that analysis can give you indications as to what's going on in the system.

When reviewing the oil sample results, operators should note the type and degree of contamination. If the oil sampling contains metal, it indicates an impending failure of a pump or cylinder. Understanding oil sampling trends is critical to understanding the condition of the equipment.

“Extreme environments require extreme monitoring and filtration,” Godwin says. “Oil filters should be changed when the visual indicators show that they are dirty. Air breathers should be changed on an hourly schedule based on how dusty and dirty the environment is. All ingression points on the reservoir should always be sealed to prevent dirt and debris from finding its way into the system.”

In addition to oil sampling, another important maintenance task is to log the time between filter changes. If the oil filters become clogged more often over time, this could be an indication of external contamination getting into the oil or an internal breakdown of hydraulic components.

Temperature also plays an important role in maintaining a baler because it impacts how well the machine’s hydraulic fluid moves in and out of the system. If the machine is in temperatures below 50 degrees, the fluid will be too cold to work effectively. If the machine is in a hot environment, it could overheat, damaging the oil, or stop working altogether.

“Our balers will shut down before they overheat,” Godwin says. “If they didn’t, the wear properties of the oil would deteriorate, and the lubrication and functionality would be compromised.”

Godwin and Farmer agree that facilities using balers should have spare parts on hand to avoid downtime or costly repairs. This also prevents high costs of expedited work orders and parts. Pumps, valves, transducers, filters and breathers are components that are necessary to have on hand to avoid excessive downtime in the event of failure, they say.

“I try to look at those critical spares that are going to take your machine out of operation if not replaced,” Farmer says. “They’re also simple, relatively inexpensive things to keep on the shelves.”

Farmer says If maintained properly, operators will get multiple years of service from their balers. Proper maintenance and scheduled cylinder rebuilds will allow balers to last decades.