ECRS

Draglines

Rack Gear on Bucyrus Model 1570W Dragline

survey of damages
This rack gear segment was found to be cracked in the roots of three adjacent teeth. The worst of these cracks extended almost completely across the width of the gear along the root of the tooth, thru the 4 ½” thickness of the rim, and down the inside wall 10”. This crack severed over 50% of the cross sectional area of the gear rim. The cracking in the roots of the two adjacent teeth was similar to the worst crack but to a lesser degree. The total cracking at these three locations was found to be approximately 58”.

repair & reinforcement procedures performed
All three cracks were repaired over their entire lengths utilizing metalock® and metalace repair components. This restored some of the lost strength across the crack planes. In addition to the crack repair, reinforcing plates were mounted to the back side of the gear to provide additional strength.

Cracked Center Pintle

survey of damages
The pintle of this dragline was found to be cracked circumferentially around a line immediately above the tub of the dragline. The cracking extended approximately 1/3rd around the circumference of the pintle and completely thru the 7” wall thickness.

repair procedures performed
A series of masterlocks, metalocks® and metalace were incorporated into the repair design for the pintle. The masterlocks had gussets for added strength and were installed every 8 inches along the entire length of the cracking. Metalocks® and metalace were installed along the remainder of the cracking.