Problem prevention

As production ramps up and recyclers struggle to keep up, it’s easy to let details such as preventive maintenance slide. However, recyclers who ignore this critical area could be setting themselves up for extended downtime in the future, as it could take as long as two weeks to rebuild a busted hydraulic cylinder, according to Mike McChrystal, president of OBC Inc. In addition to the associated production delays, such an issue could set a recycler back as much as $30,000 in repair costs alone.

McChrystal says he has seen a number of baler maintenance sins in the last 20 years, though he says most of them are related to poor housekeeping and general maintenance. McChrystal established Cleveland-based OBC Inc. as Ohio Baler Corp. in 2001, though his experience with baling equipment dates back to 1994.

OBC Inc. is a distributor of and service and support provider for baling equipment manufactured by Harris, Cordele, Ga., and Waste Processing Equipment, Rainsville, Ala. In addition to selling and servicing new balers from these manufacturers, OBC also reconditions and resells a range of used baling equipment.

In the Q&A that follows, McChrystal shares some of the common problems that can arise if operators shirk common preventive maintenance tasks or ask too much of their balers.
 

Recycling Today (RT): What are the most common preventive maintenance tasks that baler operators overlook?

Mike McChrystal (MM): Typically, it’s housekeeping items—cleaning behind the rams, cleaning sensors, changing breather filters, blowing dust/debris out of the oil cooler and shear knife adjustment.
 

RT: If preventive maintenance is ignored, what are the likely results?

MM: Different items will cause different scenarios. Improper knife adjustment will cause expedited floor liner wear as well as cylinder leaks. Not changing filters or oil in the recommended time frame (or based on physical inspection) can cause contaminants to damage pumps and valves, resulting in slow operation of the system. If the oil cooler isn’t cleaned properly, oil can overheat and burn up cylinder seals and pump cartridges or can destroy the viscosity of the oil itself.
 

RT: How common is it for recyclers to encounter problems with their baler’s hydraulics?

MM: It probably happens at least once or twice a year, on average.
 

RT: What can inadequate hydraulic system maintenance result in?

MM: In addition to the issues I mentioned earlier, pump and cylinder damage could result.
 

RT: If pump and cylinder damage results from improper hydraulic maintenance, what kind of repairs will be necessary? How much can recyclers expect to pay for such repairs and how much downtime will be required?

MM: You may have to replace or repair the pump and will be down a few hours for that.

If the cylinder needs to be rebuilt, you will probably be down for one to two weeks and spend $5,000 to more than $30,000.
 

RT: How common is it for recyclers to put too much stress on their balers? How can recyclers be sure to avoid this?

MM: This happens quite often.

To avoid it, operators should check pressures and feed the baler evenly, wait for the system to decompress before switching direction and keep the [shear] blades sharp and adjusted.
 

RT: How can operators know if they are putting too much stress on their baler’s cylinder or chamber?

MM: Too much stress can cause structural breaks in the baler or overheating of the hydraulic system.

When knives are not adjusted properly, shear jams can occur, causing knife bolts to snap, oil to overheat and potential structural damage.
 

RT: How can an operator tell that the blade is ready for replacement?

MM: It will have a rounded edge to the point where it cannot be sharpened with a grinder.

Also, if there is over a 0.02-inch gap that cannot be adjusted any closer, blades should be rotated or changed.
 

RT: What are some common mismatches you see between an application or material and baler style?

MM: In order to bale certain materials, either a specific type of baler is needed or certain options need to be available for use on the baler. I’ve seen pretty much every mismatch imaginable—probably the most common is companies trying to bale a slick coated material in a single-ram system with not enough ram face PSI (pounds per square inch of pressure) and chamber tension. Bales can come out and fall apart upon handling or loading on a trailer.
 

RT: What rules of thumb can recyclers use to match their applications to the right baler style?

MM: They can ensure the baler has a big enough hopper for the size of the material they are going to put through it, enough power to shear through the material they are processing and enough speed for the production they need.
 

RT: How can poor housekeeping or operating a dusty and dirty baler affect the baler’s performance?

MM: Sensors will give inaccurate readings, and excessive dust can cause a decrease in the effectiveness of the oil cooler.

For a two-ram baler, dusty and dirty operations can cause issues with the wire tier.
 

RT: What can result from inaccurate sensor readings?

MM: Overheating or overpressuring the baler’s hydraulic system and producing undersized or oversized bales.

A customer of ours recently had the sensors on the bale door travel rod malfunction. This caused the baler’s eject ram to extend into the bale door, resulting in extensive damage to the machine.
 

RT: How often should operators check the shearing blade gap distance and why is that important?

MM: The knives should be checked biweekly; this will prevent premature wear on the liners as well as damage to the frame and cylinder seals.
 

RT: What qualifications or skills should a baler maintenance person possess?

MM: Maintenance personnel need to have a good understanding of the electrical and hydraulic operations of the baler; someone who can read electrical and hydraulic schematics [also is important].

For two-ram balers, it’s important to understand the wire tier and keep it clean and lubricated.

We are happy to talk through potential troubleshooting ideas over the phone when issues arise. When there is a good maintenance person in front of the baler who we can talk to and who understands how everything works, we have much higher success correcting the issue and reducing downtime without incurring the expense of a service visit.
 

RT: What are some basic interview questions recyclers can ask of potential maintenance personnel to determine that they understand the basics of maintaining and repairing a baler?

MM: First, they should be able to understand electrical and hydraulic schematics and how each system works. Changing and adjusting the blades are key; they need to understand and have the ability to do so.

Mike McChrystal is president of OBC Inc., Cleveland. More information on OBC is available at www.obcbaling.com.