STC-MTV Five-Axis Mill-Turn Machining Centers

July 01, 2020
STC-MTV Five-Axis Mill-Turn Machining Centers for Hard Metal Machining

With 70 HP all-steel geared head spindles offering torque ratings up to 1,200 ft lbs., plus 200 bar/3,000 psi high pressure coolant for integrated turning, Starrag’s new STC-MTV five-axis mill-turn machining centers are specifically targeted for hard metal machining of a wide range of workpieces. In the aerospace engine industry specifically for casings and gearboxes and in the energy industry for oil and gas applications.

The two new machines, models MTV 1000 and MTV 1250 offering 8,000 rpm/700 ft lbs. of torque and 4,500 rpm/1,200 ft lbs. plus 200 bar/3,000 psi high pressure coolant for integrated turning, are joining the STC-MTV family of horizontal machining centers.

These new MTV models promise unrivalled and highly effective single set-up milling, boring, drilling and tapping, as well as turning of materials such as Ti6AL4V and Ti5553 titanium alloys, nickel-based super alloys and high alloy steels, providing superior surface finishes on even complex and thin-wall parts.

Workpieces weighing up to 11,000 lbs. can be processed on the MTV 1250 (up to 6,613 lbs. on the MTV 1000) within the machines’ X, Y and Z axes travels of 67 x 82 x 74 inches (MTV 1000) and 86 x 82 x 74 inches (MTV 1250), and both machines offer rapid traverse rates of 1,770 inches/min. Additionally, component diameters of up to 74 inches and 94 inches on the MTV 1000 and MTV 1250 can be accommodated.

High metal removal rates are guaranteed with the best-in-class, all-geared A axis spindle drive, where the compact 1D-head with minimal distance between the spindle nose and A axis enables the use of very short tools and large bearings. This provides ultimate levels of stability and rigidity compared to conventional motor spindles. 

The virtually wear-free steel worm wheel boasts high stiffness and excellent damping. Indeed, a specially coated damping disk in the 1D-head, combined with optimal parameter settings from the Siemens 840D CNC, makes heavy roughing possible, semi-finishing and finishing in 5-axis operation.  

Integrated high-pressure coolant permits highly efficient one-hit turning and the machines’ 30 HP angular automatic milling head enables easy access to internal surfaces and features, thus further optimizing single set-up operation. The angle head is loaded automatically from the tool magazine and tools can also be automatically changed into/out of the head.

The C axis CNC rotary table offers 500/400 rpm with torque ratings of 2,950/4,425 ft lbs. on the MTV 1000 and MTV 1250,.

As is widespread practice throughout the Starrag range, STC-MTV machines can be used stand-alone or integrated into a cell or flexible manufacturing system and, if required, with other Starrag machines and utilize central tool handling and pallet transport/storage. They can also be integrated with additional processes such as co-ordinate measuring, part marking, deburring and washing.

Related Glossary Terms

  • alloy steels

    alloy steels

    Steel containing specified quantities of alloying elements (other than carbon and the commonly accepted amounts of manganese, sulfur and phosphorus) added to cause changes in the metal’s mechanical and/or physical properties. Principal alloying elements are nickel, chromium, molybdenum and silicon. Some grades of alloy steels contain one or more of these elements: vanadium, boron, lead and copper.

  • alloys


    Substances having metallic properties and being composed of two or more chemical elements of which at least one is a metal.

  • boring


    Enlarging a hole that already has been drilled or cored. Generally, it is an operation of truing the previously drilled hole with a single-point, lathe-type tool. Boring is essentially internal turning, in that usually a single-point cutting tool forms the internal shape. Some tools are available with two cutting edges to balance cutting forces.

  • centers


    Cone-shaped pins that support a workpiece by one or two ends during machining. The centers fit into holes drilled in the workpiece ends. Centers that turn with the workpiece are called “live” centers; those that do not are called “dead” centers.

  • computer numerical control ( CNC)

    computer numerical control ( CNC)

    Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.

  • coolant


    Fluid that reduces temperature buildup at the tool/workpiece interface during machining. Normally takes the form of a liquid such as soluble or chemical mixtures (semisynthetic, synthetic) but can be pressurized air or other gas. Because of water’s ability to absorb great quantities of heat, it is widely used as a coolant and vehicle for various cutting compounds, with the water-to-compound ratio varying with the machining task. See cutting fluid; semisynthetic cutting fluid; soluble-oil cutting fluid; synthetic cutting fluid.

  • flexible manufacturing system ( FMS)

    flexible manufacturing system ( FMS)

    Automated manufacturing system designed to machine a variety of similar parts. System is designed to minimize production changeover time. Computers link machine tools with the workhandling system and peripherals. Also associated with machine tools grouped in cells for efficient production. See cell manufacturing.

  • gang cutting ( milling)

    gang cutting ( milling)

    Machining with several cutters mounted on a single arbor, generally for simultaneous cutting.

  • milling


    Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.

  • rapid traverse

    rapid traverse

    Movement on a CNC mill or lathe that is from point to point at full speed but, usually, without linear interpolation.

  • stiffness


    1. Ability of a material or part to resist elastic deflection. 2. The rate of stress with respect to strain; the greater the stress required to produce a given strain, the stiffer the material is said to be. See dynamic stiffness; static stiffness.

  • tapping


    Machining operation in which a tap, with teeth on its periphery, cuts internal threads in a predrilled hole having a smaller diameter than the tap diameter. Threads are formed by a combined rotary and axial-relative motion between tap and workpiece. See tap.

  • turning


    Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.