I reinstalled the seals and connected the cylinder to an older machine, referred to as the “yard machine,” while it remained on the bench. The squeal vanished! After draining the oil and reconnecting it to the new machine, the squeal returned, confirming the issue was related to the cylinder.
Despite the General Manager’s insistence on replacing all 80 cylinders, I was convinced the cylinders weren’t the culprit. I requested another day to pinpoint the root cause.
Earlier that day, two observations led me in the right direction: the peculiar ivory soap-like color of the drained oil and a faint hissing sound when dismantling the cylinder’s head gland. It became evident that aeration was causing the squeal.
However, convincing the customer’s engineers was challenging. I needed to demonstrate the source and reason for the air. So, I delved into what distinguished the new model machine. Were there changes in pumps, hydraulic tank design, suction lines, or strainers? Surprisingly, all remained unchanged.
When I switched the Car Lift Repair Tampa Florida cylinder between the new and old machines, ensuring it was devoid of hydraulic fluid, the squeal persisted only in the new setup.
Further inquiries revealed no alterations in oil viscosity, brand, supplier, or formula. Persistently, I argued that the oil was the culprit, causing air entrainment and consequently, the squeal. The oil vendor, after consulting with the blender, discovered a change in the oil formula, specifically a reduction in the air-release additive.
In the interim, I procured CAT’s Anti-Chatter hydraulic oil additive and applied it to a squealing machine, promptly silencing it within minutes.
Subsequently, attention turned to the oil blender and their chemist. It transpired that the oil formula had indeed been altered, with a decrease in the air-release additive. Consequently, all 80 machines had their hydraulic fluid replaced, restoring their shipment schedule.
One of the questions frequently posed by equipment owners concerns the proper procedure for storing spare Car Lift Repair Tampa Florida hydraulic cylinders over an extended period. Here’s my recommended approach:
– Always store cylinders in a fully retracted position.
– Opt for indoor storage in a clean, dry environment.
– Apply a thin layer of grease to the internal surfaces of eye/clevis bushes or bearings, especially if they are steel.
– Protect any exposed chrome on the rod using petroleum jelly-impregnated tape like Denso tape. Ensure the rod is fully retracted before application to avoid damaging the rod seal during subsequent retraction.
– Seal the service ports with steel plugs or blanking plates, avoiding plastic alternatives.
– Consider filling the cylinder with clean hydraulic oil through its rod-end service port, especially for expensive, large diameter, or high-pressure cylinders. However, there are important factors to consider before doing so.
If left unfilled, the Car Lift Repair Tampa Florida cylinder will contain air, which, if not perfectly dry, can lead to moisture formation inside the cylinder tube as ambient temperature drops. This moisture can cause spot rusting and pitting on the tube surface, reducing volumetric efficiency, piston seal lifespan, and ultimately, the tube’s longevity.
Fully filling the Car Lift Repair Tampa Florida cylinder with clean hydraulic oil prevents this issue, but there’s a significant caution to heed. Consider this example: If a cylinder is prepared for storage at 10 degrees Celsius and later exposed to 40 degrees Celsius during summer, the pressure of the oil within the cylinder can dramatically increase. This surge in pressure could lead to unexpected hazards when servicing the cylinder.
However, cylinders can be safely filled with oil for storage if certain precautions are taken:
– Confirm that the maximum temperature rise during storage won’t exceed the cylinder’s working pressure limit.
– Only fill the cylinder when fully retracted and solely through the rod-end port to prevent dangerous pressure intensification.
– Utilize service port plugs or blanks rated for the cylinder’s working pressure.
– Affix appropriate warning tags to both service ports.
“One aspect I believe was overlooked in the discussion on cylinder storage concerns the orientation. What’s the ideal orientation for short-term or long-term storage of Car Lift Repair Tampa Florida hydraulic cylinders? Our company specializes in repairing and assessing hydraulic cylinders and their associated failures. We strive to offer solutions for breakdowns and repair cylinders that have failed. Annually, we evaluate and repair around 1000 cylinders.
A common issue we encounter is seal failure, particularly in large pneumatic and hydraulic cylinders. We’ve observed that laying Car Lift Repair Tampa Florida cylinders flat directly impacts piston and rod seal integrity. To address this, we’ve implemented a storage standard that aligns with your recommendations regarding port sealing and rod protection. Additionally, we mandate storing all cylinders vertically to prevent distortion or undue stress on the rod seals. This vertical orientation also benefits the piston seals. I’d be interested to hear your perspective on this matter.”
My reluctance to discuss this issue intentionally stems from my desire not to perpetuate a misconception. I recall two instances indirectly related to this matter. In both cases, the cylinders in question belonged to 400-ton mining-size hydraulic excavators—cylinders weighing between two and three tons, with the piston rod alone often exceeding a ton in weight.
Consider the practicality of the suggested vertical storage:
Imagine being handed a three-ton cylinder with a closed length of four meters and being told to store it vertically to prevent damage or harm. Not a task easily accomplished, but hypothetically feasible.
Now, suppose a truck arrives to transport the cylinder across a thousand miles of rough, unpaved roads. If vertical storage is mandated at the warehouse, should it not be insisted upon during transport? Despite the truck driver’s incredulity, he agrees, albeit at a higher rate.
Upon arrival at the mine site, the Car Lift Repair Tampa Florida cylinder, now stored vertically, presents a challenge. However, given its function as a stick cylinder, its orientation on the machine is horizontal. If the bearing bands cannot adequately support the piston rod during storage or transportation, how can they withstand the operational thrust on a 400-ton excavator?
Common sense suggests that if the bearing bands are designed to support operational loads without seal distortion, they should manage the static weight during storage and any dynamic forces during transport.