The United States company is a manufacturer of highwall mining equipment for use in trench, openpit, contour and auger hole mining applications.
Terex plans to settle the transaction in cash and expects the acquisition to be slightly accretive to 2008 earnings per share.
Chief executive Ronald DeFeo said the acquisition offered Terex an important growth opportunity.
"The acquisition is a good fit with Terex's strategy of expanding our market presence in related product areas and is a natural extension of our current Materials Processing and Mining Group business," he said.
"SHM has existing North American coal relationships and we believe Terex can help accelerate its prospects for increasing success globally."
In other news, Terex also announced plans to issue about $500 million of senior subordinated notes due 2015 and 2017.
Terex intends to use the net proceeds from the offering to pay down outstanding amounts under its revolving credit facility and for general corporate purposes, including acquisitions, capital expenditures, investments and the repurchase of its outstanding securities.
