This extrusion customer produces friction material for use in automatic braking assemblies for consumer products such as washing machines and lawn mowers. This is basic profile extrusion of a proprietary heavily filled mineral/fiber material. The equipment is a Bonnot extruder with a 4” interrupted-flight screw designed to process high load materials.
Standard protection for the feed screw has been complete weld encapsulation of Colmonoy 56, nickel-based hard facing. Typical batch size is about 360 lbs. and after 150 batches (3 to 4 months production) the C56 protection has severe erosion. Flight outside diameter is also reduced and output rate becomes uneconomical and the screw is removed and rebuilt.
A rebuilt screw was coated with XC1000 to a total thickness of .010” (0.25 mm) and installed in early June 2006.
The customer was extremely pleased with the improvement to screw life and process reliability. At six months of operation the coated screw has nearly twice the life of previous screws ability. with no indication of wear. The estimated savings compared to the previous C-56 screws is $8,000 to $10,000 annually.
A visit in November 2006 provided the following information:
|Batches||Total Output||Wear Condition|
|Previous C56 Screw||150||54,000 lbs||Severe root erosion, OD reduction|
|XC 1000 Screw||184||66,240 lbs||No discernable wear, coating intact|