Case Study Of Greenco Cable Cylinder Returned Under Warranty For Evaluation
What at first appeared to be a cable tensioning issue, turned out to be an alignment issue in the application!
Greenco issued a return authorization for a rodless cable cylinder which was under warranty, and was reportedly leaking air at the cable seal. Upon receipt of the cable cylinder, the first thing we noticed is that the nylon jacket on the cables was noticeably worn down one side. Our initial thoughts were that the customer might not have tensioned the cables properly after installation, and that the lack of tension might have caused the cables to rub against the pilot washers, wearing out one side of the coating on the cables. This would result in a leak at the cable seal because the cable seal would not be able to seal against the severely damaged cable coating. Upon disassembly we did find that the cable seals were very loose fitting over the severely worn cables. This all seemed consistent with the hypothesis that the customer might not have tensioned the cables properly after installation.
However, it was then that we noticed that one of the sheaves (pulleys) had been severely damaged on one side. The thrust washer had completely worn into the side of the sheave, creating a counter-bore where there normally was not one. That was when we realized that the issue could be due to the application itself. It could be that the cylinder is installed in such a way that the trolley is constantly pulled to one side, away from the center-line of the cylinder. This would explain why the cable & sheave are both wearing out prematurely on one side.
We went ahead and replaced the cables under warranty, as a customer consideration, even though we suspected that the application was the cause. We also replaced the worn sheave under warranty as customer consideration. We then returned the worn sheave to the customer with the repaired cable cylinder, so that they could see what had happened. The evaluation provided to the customer alerted them to our findings, and we recommended that the end user should ensure that the trolley is not being pulled to one side in the application. Just in case the cables were not tensioned properly, in addition to the suspected pulling issue, we also recommended that the end user should properly tension the cables after unit is securely mounted. We provided them with page 6 of the Greenco catalog for the cable tensioning specifications. The customer made the recommended changes to their cable cylinder application and they are now running smoothly!
What Is A Trac-Trol® Guided Cylinder?
The Trac-Trol® is a guided cylinder, unlike the Cable-Trol® which is unguided. The trolley on the Trac-Trol® incorporates four linear bearings which ride on two guide rods. The trolley itself is therefore guided and supported by the guide rods. For longer stroke lengths, optional rod supports can be incorporated to maintain maximum load capacity regardless of stroke length. Those guided cylinder models are called supported Trac-Trols® because they include the rod supports. Unsupported Trac-Trols do not include the rod supports, but have the advantage that the bearings in the trolley completely encircle the guide rods. The bearings in the trolley of a supported guided cylinder do not completely encircle the guide rods, because they have to be able to pass over the rod supports. For both supported and unsupported models, load weights can be mounted directly to the Trac-Trol trolley without any other guides or supports. The load weights can even be above or off to the side of the trolley, provided the appropriate guided cylinder size is chosen based on the load weight.
Benefits to our Trac-Trol Guided Cylinder:
- Strokes up to 24 feet
- Supported or unsupported guided cylinder arrangements are both available
- Two bearing options: Re-circulating ball bearings on hardened ground shafts are standard, self-lubricating or thermoplastic bearings on stainless steel shafts are optional
- Internal adjustable cushions are standard, external shock absorbers are optional
What Applications Use Cable Cylinders?
You name it, Greenco cable cylinders are in it! Cable cylinders can be used in a variety of applications from loading production lines at tire manufacturers, door making machinery and opening/closing doors at major theme parks. Our Cable-Trol® cable cylinders can also be designed for wash down applications such as moving sprayers within car washes and milk processing plants. We offer a variety of accessories and options including reed switches, low friction seals, cable wipers and different mounting options to fit your needs. If you are looking for quality cable cylinders that can stand the test of time and are competitively priced, then rely on Greenco cable cylinders. For more information on our products see Cable-Trol Cable Cylinders.
Greenco "Launches" Innovation
We recently had a request for a Cable-Trol which would be capable of launching an unmanned aircraft! The unit had to have 40 feet of stroke, and had to be designed for maximum speeds, in the range of 60 miles per hour. We were able to meet the unusually long stroke length by splicing two tubes together, and were able to achieve the high speed requirements by including a special array of oversized ports. The motion picture industry also uses high speed Cable-Trols in order to launch special effects into the air at high speed! If you are living life in the "fast lane", you should consider using high speed Greenco Cable-Trol. Don't worry, if you prefer slower speeds, the Cable-Trols can do that as well. At Greenco, we welcome all special requests!