Autogenous 1200-inch Mill Trunnion Repair — Oct 06, 2010 Supplied information continued: Over time the ground product eroded a section of trunnion from the back side resulting in stress fatigue cracks. Read Full Case Study
Paper Mill Suction Roll Repair — Oct 06, 2010 After dye penetrant testing, approximately 15” of crack revealed. Read Full Case Study
Propeller Blade Hub Repair — Oct 06, 2010 Inspection using mag particle reveals the cracked area of approx. 18 inches Read Full Case Study
Hoist Drum Repair — Oct 15, 2010 Continual operation of hoist drum on a open pit operation resulted in cracking that threatened strength of the unit. Read Full Case Study
60 Ton Crane Bearing Housing Repair — Oct 15, 2010 Bearing housing for a 60 ton crane was mismachined, while the unit performed adequately for years, cracking appeared. Read Full Case Study
Hydraulic Cylinder Repair — Oct 15, 2010 Combination of poor casting and overloading this 2,500 ton capacity cylinder resulted in a crack. Read Full Case Study
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Blade Hub Repair

Ore Carrier Suffering from Ice Damage Ready to Headout in Just Days

The Problem

With hub removed from the ship's propeller shaft, close-up view displays areas of the cracks in the hub.

The Fix

Crew stitches up over 150" of crack on the hub.

The Results

Hub being installed onto the tail shaft. Estimates in replacing the heat-fitted hub ran to approximately $250,000 and nearly six months of lead time Five days of stitching at 10% of the estimated replacement cost brought the hub back into service. This type of repair for hub securing these enormous seven foot blades had never been attempted before. As proof of the strength of the repair, the ship set out on Lake Superior later in early spring. This time the ice sheared off the propeller blades. After ballasting the tanks, an inspection revealed the hub was as good as new. New blades were replaced.