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Campro Precision Machinery manufactures a family of bridge mills with 8 sizes up to 204” x 122” travels. The machines offer the highest accuracies of any bridge mill on the market and can machine large parts efficiently with its rigid design.
WHAT IS A BRIDGE MILL?
A bridge mill is a vertical machining center with a fully supported, extended Y-axis. A bridge mill is constructed with a base/bed casting and a one-piece bridge structure that is bolted to the bed. Along the bridge structure is the Y-axis, and along the length of the bed is the X-axis.
WHAT MAKES A BRIDGE MILL DIFFERENT FROM A DOUBLE COLUMN MACHINING CENTER?
A double column machining center has the same design, but because it is much larger, the bridge structure is made up of three separate components—2 vertical columns and a horizontal cross beam.
HOW IS A BRIDGE MILL DIFFERENT THAN A GANTRY MILL?
A gantry mill is similar in construction, but the entire bridge (gantry) moves along the X-axis rather than the table moving, as with the bridge mill or double column.
HOW IS A BRIDGE MILL DIFFERENT THAN A VERTICAL MACHINING CENTER?
There are several types of vertical machining center construction—L-frame, C-frame, and bridge-style. The main difference between these machines and a bridge mill is that the Y-axis travel on a vertical machining center is limited due to the design.
WHAT ARE THE BENEFITS OF A BRIDGE MILL?
The extra travel provided by the bridge mill allows for the manufacturing of much larger, longer parts than on a vertical machining center, since machining on a vertical machining center is restricted by bed size—particularly the Y-axis. A bridge mill’s larger work envelope provides greater opportunities for manufacturers in the die/mold, aerospace, automotive, and other industries. Additionally, a bridge mill offers much easier access to the table and spindle for part loading / unloading as well as tool maintenance.
Above is an excerpt from a write up about Bridge Mills from our friends at Okuma.