Large Sand Casting Value Engineered with Drastically Improved Price and Durability

Objective
Redesign an existing weld-fabricated turret secondary machining to improve durability and longevity and significantly reduce costs.

Considerations
This turret, used to maneuver powerful mowing attachments affixed to a heavy, rugged arm, is already in use on a large number of tractors. Since the dimensions and configuration had to remain the same, we were asked to review the manufacturing processes used to create the part and suggest production techniques and materials that could increase its useful life while reducing costs.

Solution
The original turret was welded together from several different pieces. The mowing arm is designed to tackle a wide variety of challenging conditions, and these welded areas made the part weaker than it could have been.

1. We evaluated all of the possible manufacturing processes, choosing sand casting to reduce both time and complexity in manufacturing. Casting provided the turret with the benefits of full penetration welding without the time and cost that process requires.
2. Instead of steel, we fabricated the part from 80-55-06 ductile iron to increase strength and reduce the risk of porosity and inclusions created during the cooling process.
3. The sand-cast turret was heat treated to increase hardness, and machined to match the configuration of the existing part, facing off the bearing race and drilling a bolt circle, which was then drilled and tapped.

Results
Before value engineering, the turret was a costly weak link in the machine. The strength of the new turret, the result of molding ductile iron instead of welding steel, has dramatically decreased costs by moving the weak link back to its intended point - an inexpensive pin. Additional benefits were reduction of final unit cost by 60% and lead times by 4 weeks.

CONTACT:

Cypress Industries
214.550.1226
info@cypressindustries.com