mold shift

mold shift

[′mōld ‚shift]
(metallurgy)
The mismatch of mold halves at the parting line, resulting in a casting defect.
References in periodicals archive ?
The metal mold material in permanent mold eliminates the potential for mold shift, leading to a uniform shape and excellent dimensional properties.
To compete with its diecasting competitors in England, Europe and South Africa, Riverside must keep mold shift to 0.001 in.
"Disa promised mold shift of just 0.25 mm, and they met that promise."
Wescast Industries Inc., Brantford, Ontario, Canada, the world's largest manufacturer of exhaust manifolds for passenger cars and light trucks, was experiencing mold shift on their existing molding machines at its Wingham, Ontario, Canada facility.
The machine also features Detent Cylinders integrated onto a rigid platen that lock the drag flask in alignment with the platen, eliminating the possibility of mold shift; a new Autolock hydraulic pattern clamping system that eliminates the need to bolt down a pattern after pattern change and provides a tree "drop-in pattern change" that takes only seconds to complete; and an inverted hose tracking system that creates additional clearance for the removal and insertion of patterns during changes.
"In green sand casting, one big thing we look at is eliminating mold shift. You have to have better control over the squeezes and movements of the molds when you close them."
The machine also incorporates new technology in the squeeze station to reduce mold shift. The shift reduction is achieved because of the machine's rigid squeeze station, draw guides with linear shafting and precision bushings, a rigid cope flask with an eject system and draw pins with replaceable seats.
For WAFCO, one of the key decision makers for the new" system was zero mold shift. "In addition, we have experienced an increase in overall mold hardness and uniformity with less finishing," said Ziarnik.
Summit Indexing Mold Handlers promote gentle mold movement without mold shift through the use of Hydro Proportional Valves and oversize Shock Absorbers to decelerate moving molds.
One of the keys to the mold handling system is its ability during indexing to promote gentle mold movement without mold shift through the use of hydraulic shock absorbers and ultra high density polyurethane.
The system has allowed the foundry to achieve more than a 90 mold hardness consistently across the cope and drag, improving the casting finish, according to Grenier, who added that the foundry has seen no mold shift on the system, leading to the better quality finish necessary for the firefighting equipment castings it produces.