NASHVILLE, Tenn.—Technical advancements in non-destructive casing analysis (NDA) are making the processes faster and more affordable, heightening interest among retreaders. Despite price tags of $130,000 to $250,000 for the more technologically advanced holography- or shearography-based systems, the possibility of detecting potential zipper and other sidewall problems is leading major retreaders to consider adding such NDA processes to their manufacturing flow, according to a sampling of opinion from attendees at the recent International Tire and Rubber Association Expo in Nashville.
Goodyear, for one, has determined it needs to enhance its casing inspection procedures and is evaluating a non-destructive system this summer at several locations before making a final determination, according to ``J.B.'' Jaboor, director of retreading services for Goodyear.
Goodyear officials declined to say which type of NDA system it is evaluating, but once the decision is made to go ahead, the company will start outfitting its 68 company-owned plants and will recommend the choice to its 168 independent Goodyear Authorized Retreaders (GAR), Mr. Jaboor said.
Among the key capabilities an NDA system must have are the ability to detect potential sidewall defects and a complete cycle time of no more than two minutes, according to feedback from the GAR network, Mr. Jaboor said.
To date, Goodyear's casing evaluation process has consisted of visual and nail-hole inspections.
With the launch of its network of licensed retreaders last year, Michelin Retread Technologies Inc. made casing inspection a priority, requiring MRTI franchisees to use both X-ray and shearography in their casing examination procedures.
Other independent retreaders now have two possible sources for holographic or shearography-based NDA equipment.
Both Steinbichler Optotechnik GmbH and Marangoni Tread North America Inc. exhibited holographic inspection equipment designed for the retread plant environment.
Steinbichler—the German firm that supplies Michelin with its equipment—said it is setting up a North American service point in Ohio, on the premises of the Dutch tire machinery maker VMI Americas Inc.
Steinbichler will offer one machine equipped with automated loading and unloading ancillaries and one without, according to Mandred Adlhart, in charge of sales and marketing for the German firm.
The company shared booth space with German extruder maker A-Z Formen- und Maschinenbau GmbH, the principals of which will also act as agents for the Steinbichler line.
Marangoni also will offer its shearography machines in two versions—the fully automated ITT-S-2000 model for medium to large retreaders, and the semi-automated ITT-S-1000 model for medium-sized firms. Marangoni will offer a lease-to-buy option on its equipment, which starts at around $180,000.
The equipment divides a tire into eight segments, and the 2000 model allows the operator to examine a single segment individually or all eight at once on a video screen. The 1000 model does not allow individual segment inspection. Image resolution is from 2 to 5 square millimeters, Marangoni said.
Total cycle time for an inspection with the 2000 model is two to two and one-half minutes, floor to floor, and four minutes for the 1000 model, Marangoni said. It's also possible to archive inspection data for each casing, and provide a printout for rejected casings to send to the customer.