Sunnen has updated the SV-20 with a ball-screw servo stroking system and new PC control to create a workhorse honing system ready for anything from big engine blocks to oil field components.
The Sunnen SV-25 cylinder hone introduces a Siemens touchscreen PC control, with a host of other enhancements, to its predecessor SV-20 platform. New features include spindle reversal, automatic stroker-brake checks and automatic tool protection that verifies an unobstructed stroke before starting a cycle. Combined with Sunnen-made abrasives, tooling and coolants, the U.S.-built SV-25 is engineered to allow novice operators to produce ideal bore roundness and surface finish with just a few hours of training.
The variable-speed 5.5 HP (4.1 kW) spindle motor produces 50-600 RPM. A separate 3.4 HP (2.5 kW) servomotor produces up to 100 true vertical strokes per minute up to 20". The linear stroking drive maintains concentricity with the bore throughout the full stroke to produce a consistent diameter from top to bottom.
The system hones bores with inside diameters from 0.75 to 8" (19-200 mm). A 48" x 30" (1,219 mm x 760 mm) work envelope, front-loading design and weight capacity up to 1,325 lb. (600 kg) combine for versatility in processing a wide range of other large parts, such as compressor bodies and pumps. The SV-25 accepts engine blocks as large as the Cat 3126 in-line six and Ford 7.3 L V-8 (International 444) - even "mountain motors" with deck plates can be honed in one set-up on the optional rollover fixture.
According to Sunnen, the new spindle reversal feature duplicates the capabilities of machines used by OEM engine manufacturers. Reversal can be used anytime in the process, but is especially helpful during the finishing strokes. It requires programmable spindle control and a honing tool/abrasives that can be run in both directions. Reversal helps create a slightly rounder bore and aids in achieving the desired surface finish. It causes the honing stones to take out any less-than-round shape left after initial passes, while shaping up and dressing the stones themselves. Reversing the spindle, with abrasives or a brush, also aids in removing folded-over metal and cleaning out debris hiding in the valleys of the surface. On a more subtle level, reversing the tool applies force to the block from the opposite direction, allowing the workpiece to breathe.
The Siemens control ensures automatic, consistent bore-to-bore geometry and finish without constant adjustment by the operator. The 15" color touchscreen lets operators follow programmed honing "recipes" and monitor a real-time display of the full-bore cross section during the process. The control can store multiple honing programs, and a USB port allows offline storage. The control's programmable Auto-Dwell feature automatically corrects taper anywhere in the bore for unattended operation, while two-stage honing tools with diamond or CBN abrasives can complete roughing and finishing operations in one pass for high productivity.
Left/right positioning of the honing column on its 33" X-axis (838 mm) is accomplished with a machine-mounted hand wheel immediately below the control. The machine comes standard with a 55-gallon (208-liter) internal coolant system equipped with two standard canister filters.
The SV-25's rotary servo tool feed system can be used with two-stage hone heads to complete roughing and finishing without stone changes for faster processing times. The machine is compatible with all of Sunnen's past and current tooling for CK/CV/SV-series machines, including diamond abrasive hone heads and brushes, GHSS single-stage hone heads with CBN or diamond abrasives and brushes and GHTS hone heads for two-stage honing with CBN or diamond abrasives.
The SV-25 is available with a 400 V/50 Hz/3 Ph or 460 V/60 Hz/3 Ph electrical system. Options include a T-slot base, heavy-duty manual rollover cradle for engine blocks and a full-feature automation interface.
For more information contact:
Sunnen Products Company
7910 Manchester Rd.
St. Louis, MO 63143
800-325-3670 / 314-781-2100
sales@sunnen.com
www.sunnen.com