The world’s first 4-meter linear motor ballscrew grinder
The GS:TE 4-Meter has a grind length of 4-meters and swings over 350mm.
The machine has a cast polymer base with moving wheel head design and no mechanical drives on the principal axes. The wheel in feed (X-axis) and work traverse slide (Z-axis) are driven by linear motors. The work head (C-axis) is driven by a torque motor integral with the spindle and boasts a better than 10 arc seconds index accuracy.
This massive machine for grinding ball screws (and nuts with the internal attachment) operates with no ball screws–truly a “mother” machine tool.”
A recent runoff for a customer consisted of grinding a 790 mm ISO Class 0 (lead error of less than +/- 7microns in the length) ball screw as well as a 3.5 meter ISO Class 1 ball screw (lead error of less than +/- 32 microns in the length) both ground in one setup without removing either screw for lead inspection during the grind.
Other GS:TE 4-Meter Thread Grinder features include:
- Two-axis, behind-the-wheel dresser
- Headstock mounted dresser with outboard bearing support for crushing or form roll dressing
- Power helix
- Internal grinding capability
- On-machine inspection via Renishaw probe
- Drake PartSmart™ software programs for customer parts
The worktable is equipped with a precision tailstock with manual adjustment for product lengths from 25mm to full travel length. A pneumatic powered quill with male, carbide-tipped, Morse taper center is provided. Tailstock position feedback provides the operator with indications of work piece thermal growth during the grind process via a positioning sensor.
The machine is equipped with 6 manual 3-point steady rests for centering and supporting long parts during the grind cycle. The Fanuc control is equipped with steady-rest compensation software for CNC taper correction. Additional steady rests are available as well as hydraulic, self centering, follow-down steady rests. Standard rest jaws are provided for 20-100mm diameter work.
Diamond Roll Truing.
A 2-Axis (W- and Y-axes) electric motorized rotary diamond dressing unit is mounted in the wheel head behind the wheel or on the work head depending on the machine configuration required. Wheel forms are generated by simultaneous CNC contouring on W- and Y-axes or by plunging with a form roll. One diamond contouring roll included. Optional Acoustical Emissions Monitoring (AEM) is available.
|Work Piece Range:|
|Work Length Between Centers (Max)||4200 mm|
|Grind Length Maximum||4000 mm|
|Thread Diameter Maximum||300 mm|
|Work Diameter Swing (Max)||440 mm|
|Work Piece Weight (Max)||400 kg|
|Programmable Lead||0 to 999 mm|
|Lead Angle Range||±40°|
|Programmable Thread Starts||999|
|Contour Dress Thread Forms||60º, 55º, Acme, Trapezoid, Buttress, Gothic Arch, Radius, ISO, DIN, Whitworth, API, Others.|
|Dressing Methods||Diamond contour or form roll, single or multi-rib|
|Form Width x Depth||25 mm x 18 mm|
|Wheel Spindle Power||22 kW|
|Wheel Peripheral Speed (vc is constant)||50 m/s new wheel|
|Wheel Spindle Bearing Construction||Hydrostatic/2000 RPM max|
|Standard Grinding Wheel Range:|
|Outside Diameter||(Spent Wheel) 500 mm (400 mm)|
|Width||12 to 70 mm|
|Number of CNC Axes||6 (includes helix)|
|Work Head Motor (C-axis)||Fanuc Torque Motor|
|Work Head Speed||Up to 200 rpm|
|Work Head Positioning Encoder||±2 arc seconds|
|Work Spindle Thru Hole Diameter||150mm|
|Work and Wheel Axes (X, Z)||Fanuc Linear Motors|
|Dresser Cross and Feed (Y,W)||Fanuc Servo & Ball Screws|
|Linear Axes Position Feedback||0.05 micron Heidenhain Scales|
|Wheel Head Angle (A-axis)||Fanuc Servo & Gear Set|
|Linear Ways||Rails and Recirculating Roller Cars|
|Base Construction||Cast Polymer|
|Total Electrical Requirements||52 kVA|
|Overall||7.4m W x 2.4m D x 2.4m H|
|Work Holding Height||1.4 m above floor|
|Coolant Discharge Height||0.35 m above floor|
|Machine Color||RAL 9003 Signal White or specify|
|Guards||Stainless Steel, LEXAN|
|Minimum Grind Coolant Requirements:|
|Grind||80 lpm @ 7 bar|
|Bed Wash||50 lpm @ 1-2 bar|
|Total Flow||130 lpm|
|Diamond Dressing Rolls:|
|Diameter||114 to 125 mm|
|Width||Up to 32 mm|