This inexpensive test can give crane owners a heads-up before gearbox issues become severe
Janne Kuumola, Project Manager
If you could put on a pair of magic glasses and see inside your crane’s sealed gear case to check for wear, would you do it? Most maintenance professionals would quickly answer yes. Then, the prudent ones would ask, “wait–how much will this cost?”
Good news, prudent managers. The answer is, not much. But the benefit of knowing what’s going on inside your crane’s gearbox can add up to thousands, or hundreds of thousands of dollars saved in terms of downtime, or in the worst case, accidents avoided.
So, what real-world tool will give you this information? Not a pair of magic glasses, but rather, an in-depth analysis of the oil currently inside your gear case.
Global crane technology leader Konecranes offers Oil Analysis as a supplement to its service agreements. When combined with routine inspections and preventive maintenance, the cost of doing an Oil Analysis is very low. But the list of benefits customers can expect from the information it reveals is substantial.
What does an Oil Analysis reveal?
First, an Oil Analysis will tell you what kind of oil is residing in your gear case, and whether it conforms to the manufacturer’s recommendation for your crane. If the crane is old or if there are no records of previous maintenance, the analysis will note if the oil inside is of the correct type and viscosity grade for your crane, and for the ambient conditions of the facility and geographic location. For example, viscosity requirements for cranes in cold climates can be substantially different from those operating in hot climates. In general, synthetic oil is suitable for a wider range of ambient temperatures than mineral oil with the same viscosity grade.
Next, the Oil Analysis will reveal whether the oil is clean and doing its job to lubricate the gears, or if the oil has become degraded or contaminated. Oil ages in use and gradually loses its performance, so lifting gears that require cost-intensive oils to operate need to have oil changes performed at the right time to protect machinery. On the other hand, changing oil too often without knowing its condition can waste time and money. During the oil change, the gear reducer needs to be flushed before filling with new oil, especially if the oil type is changed.
Lastly, and most importantly, the Oil Analysis identifies any wear metals suspended in the oil as contaminants–a clear indication of gear wear. The degree of contamination also gives clues to the severity of the problem–often long before any outward symptoms (such as unusual noises) are present. It must be noted that during the startup and running-in period, the generation of metal particles is higher, as seen in the results of the analysis before the first oil change, typically after about 300 hours of use. Over the remaining lifetime of your crane, Oil Analysis gives your maintenance team an opportunity to head a developing problem off at the pass months before it can cause unplanned downtime or something as catastrophic as a load drop.
How it works
It only takes a few minutes to pull an oil sample, even from a sealed gear case. A small tube is inserted into the opening where the oil is added, or through the plate or cover used for inspection access. Conducted during mandatory inspection or routine preventive maintenance, the test is performed with no loss of time and at minimal cost.
If warranted, a Safety Notification is delivered to the customer before the equipment is returned to operation that notes any urgent problems. Typically after seven days, a detailed, but easy-to-interpret color-coded report is made available online, accessed through the yourKONECRANES customer portal or delivered as a pdf. Results in the green range indicate that oil condition is satisfactory. Yellow coding indicates caution, while a red code flags a serious problem. The report provides detail on current fluid condition (viscosity, appearance), additives, contamination and wear metals found, presented side-by-side with results from the previous test.
About 25 percent of the results generated by the samples recommend an oil change because of poor oil quality. Only about five percent of the samples call for a more detailed inspection with an endoscope to evaluate possible reasons for poor oil quality relating to a high content of wearing metals.
What benefits can you expect from an Oil Analysis?
- It can help determine if an oil change is needed for equipment with an unknown previous oil change history
- It can help identify oil quality issues between scheduled oil changes
- It can provide early warning of hidden defects
- It can aid in planning maintenance actions to avoid unscheduled downtime
- It can help increase efficiency, availability, performance, productivity and safety of your crane systems and hoists
In the final analysis, Konecranes Oil Analysis operates as an inexpensive backchannel that reveals secrets your gearbox may be hiding. With this information, you can plan with our experts the optimal time for oil replacement, gearbox repairs, overhauls or the future modernization needs of your equipment.