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Tire retreading
- Cushion gum extruder (CTC)
- Retread systems for earth mover tires
- Buffing systems
- Baldwin BSEL150 endless belt strip extrusion line for OTR tire repairs
Cushion gum extruder (CTC)
The VMI-AZ Extrusion CTC (Cushion-To-Casing) system uses an extruder to directly extrude hot cushion gum onto the buffed casing surface, thus directly replacing the process of wrapping calandered sheet cushion gum around the buffed casing. Single size extruder feed strip is drawn into the extruder feed section, heated up by being plastisized in the mixing section of the extruder and then forced through the 420 mm wide CTC extrusion head directly onto the buffed casing.
Since the CTC skive filling action is an automatic process, it is far more reliable than the skive filling operation as performed by an operator with a hand held extruder. Cushion gum width is adjusted by moveable slides, which change the die opening width of the extrusion head. Specially shaped quick-change side-dies are also available so that cushion gum can be partially extruded on the casing shoulder in order to accomodate pre-cured tread with sings or contour sides.
The VMI-AZ Extrusion CTC system comes in two models, i.e.: The extruder builder CTC-SB I and the extruder builder CTC-SB V.
The main features of the extruder builder CTC-SB I are:
- Optimized for big shops
- 80 – 160 tires per 8-hour shift (cushion gumming and pre-cure tread building)
- PLC controlled, with touch screen HMI
- Automatic stretching of tread for precise splice matching
- Saves labor costs by automatic skive filling
- Saves cushion gum costs by using just one size of feed strip
- Saves cement spraying costs with correctly formulated cushion gum
- Increases product quality
The picture shows an extruder builder CTC-SB I.
The main features of the extruder builder CTC-SB V are:
- Optimized for small to big shops
- Up to 140 tires per shift
- PLC control operation, with touch-screen HMI
- Saves labor costs by automatic skive filling
- Saves cushion gum costs by using just one size of feed strip
- Saves cement spraying costs with correctly formulated cushion gum
- Increases product quality
- Discounted versions available without stitching unit and laser arm, for cushion gum application only
- Start saving costs today!
The picture shows an extruder builder CTC-SB V.
Retread systems for earth mover tires
VMI-AZ is one of the market leaders for retread systems for truck and passenger tires. Based on this experience a new system has been developed to enable retreading of earth mover tires. Main components of this system are the base constructor and the strip builder.
The base constructor consists of three PIN-Extruders attached to a special retread extrusion head that supplies rubber to the tire carcass. This set-up smears rubber onto the tire carcass while the carcass is rotating. The so called cushion to casing technology is already well known from VMI-AZ retread machinery.
The picture shows the VMI-AZ base constructor for retreading of earth mover tires.
If the base is built-up by the base constructor the tire can be moved to the strip builder position. At the strip builder a hot extruded rubber strip is supplied to the tire carcass for building-up the new tread. To ensure high precision the Shark® extruder gear pump system is used for extruding the strip.
The picture shows the VMI-AZ strip builder for retreading of earth mover tires.
Buffing systems
The picture shows the buffing machine for bus/truck, super-single and aircraft tires.
Fully automatic tire buffing systems are available for passenger, light truck and truck/bus tires in a bead range from 15” – 24”, including super single tires up to 495/45R22.5. This system comes fully computerized, however, a semi-automatic version (template controlled) is also available.
OTR tires, from 22” – 63’’, can be buffed in the new generation buffing machine. The modular design allows the end-user’s to chose from a manual, a semi-automatic, or a fully automatic version.
There is a special execution for aircraft tires, of which the software can handle “Flat-spot” and is free programmable (R1 – R4) for aircraft tires from 15” – 25” and 60” o.d.
For all machines manual (hand-) buffing are available optionally.
Baldwin BSEL150 endless belt strip extrusion line for OTR tire repairs
One of the components that is used for repairing and retreading of large OTR tires is steel cord strip. The strip is cut to length in order to replace areas in the tire that have incurred broken steel cables during the intensive use in mines.
The Baldwin belt strip extrusion line produces an endless belt strip from rubber compound and steel cords and automatically winds the produced strip onto reels ready for further use in the OTR repair shop.
The complete line consists of a dual position creel and organizer unit, an optional infrared cord heating unit, a cold-feed pin type extruder with gear pump, a pull unit, a festooner and a wind-up system tailor made to customer's needs and a highly advanced control system.
The picture shows steel cords which are pulled from the creel.
The picture shows the rubber compound added to the steel cords by a VMI-AZ gearpump extruder. Accurate control over the quality and dimensions of the produced strip is achieved by the patented VMI 3D Vision System.
The picture shows the produced strip is automatically wound onto reels.
For more information please see our brochures or contact us sales@vmi-group.com.