NEW MULTI-FEED HONING LOWERS PART COST

Sunnen's (St. Louis, MO) new patented multi-feed honing technology gives users a revolutionary choice of tool-feed modes to achieve the shortest cycle times, lowest part cost, and longest abrasive life. Multi-feed combines Sunnen's new controlled-force tool-feed with its controlled-rate feed system. The two different tool-feed modes allow the user to select the better option to suit the workpiece geometry, material and tool type/size. Multi-feed technology will be demonstrated at IMTS, and is available as an option on new machines in Sunnen's SV-1000 and SV-500 Series, as well as a retrofit for existing machines in these series.

Controlled-force honing, a new feature in multi-feed, works like cruise control to ensure the optimum cutting load on the honing abrasive throughout a cycle, irrespective of the incoming part's hardness, geometry or size variation. Depending on the application, controlled-force honing cuts cycle times by as much as 50 percent, lengthens abrasive life for lower consumable cost, and allows finer control of surface finish parameters than ever before possible. Controlled-force technology eliminates glazing of the abrasive, due to too little force, and maintains a steady, free-cutting, self-dressing condition for maximum metal removal in the shortest possible cycle time.

"In our development work, we found that more durable abrasives could often be used, resulting in more parts per set of abrasives and lower cost per part," said Dennis Westhoff, Sunnen's global business development manager. Controlled-force is an ideal choice for applications using segmented diamond or superabrasive honing tools, or where incoming workpieces have slight variations in hole diameters, hardness and geometry.

"An established honing process can be thrown off balance because of incoming part variations caused by upstream machining, heat treating or plating," Westhoff explains. "Controlled-force honing always maintains optimum feed force on the honing abrasive under these conditions to eliminate wasteful 'air cutting,' glazing or tool damage. The beauty is that if conditions allow, for example with a batch of parts requiring less stock removal, the honing cycle will be shortened significantly and automatically."

Controlled-force's ability to control the cutting load within a very fine range also allows much tighter control of final surface finish parameters. "We have been able to cut the variation of final surface finish measurement by half or more," Westhoff added. Controlled-force honing works with MMT, PH and new KRQ tools. Controlled-force honing is an enhancement of Sunnen's controlled-rate system for tool wear compensation, which is already capable of adjusting tool size in increments as fine as 0.1 µm (0.000010 in). Controlled-rate tool feeding is typically used with plated-diamond CGT honing tools, which use a sleeve of abrasive for full contact with the bore surface. CGT tools are frequently used on cast iron and powder metal workpieces, segmented bores, or parts with multiple lands, ports, keyways or crossholes in the bore. Sunnen's machine control provides up to five feed expansion profiles that can be used during a cycle for rapid part touch, cutting, sizing, finishing and spark-out.

Custom bore profiles for diesel cylinder liners are among the new capabilities introduced on the SV-500 Series vertical CNC honing system. The patented machine is ideal for profile machining of diesel cylinder-liner bores to manufacturer's specs, while eliminating the "flattening" of the crosshatch angle at stroke-reversal points, sometimes required for MilSpec parts. Bore profile display and tool-control technology allow the operator to easily achieve the desired bore shape, surface crosshatch angle, or near-elimination of crosshatch. Available with a stroke length up to 1524 mm (60 in), the SV-500 Series' 15 kW (20 hp) spindle is ideal for bores up to 300 mm (12 in) diameter or larger, depending on the application. Its powerful spindle permits high stock removal rates on exotic materials, such as titanium and compacted-graphite iron. Standard spindle speed is 0-300 rpm, with options of 0-600 rpm and 0-1200 rpm, and a maximum stroke rate of 27.4 m/min (90 ft/min). Capable of using legacy tooling from GH-210 and SV-3/SV-4 machines, it is also ideal for low to mid-volume machining of oil and gas industry components, such as gas compressors, liner hangers, telemetry units, valves, pump liners and similar parts.

An electromechanical design, the SV-500 delivers servo-accurate performance that remains consistent over time, eliminating the drift inherent to hydraulic machines. Its patented servo-stroking system brings a new level of automation and simplicity to honing complex parts, such as those with interrupted, tandem, blind or geometrically flawed bores. New capabilities include custom bore profiles, automatic geometry correction, and auto-dwell for bore straightness, ideal for blind bores. Vertical spindle orientation produces superior results with interrupted bores, where the weight of the tool and drive shaft on a horizontal hone increases the potential for washout around ports.

Equipped with the fastest, most precise linear tool feed on the market, the SV-500 Series can be configured as a single-spindle, manually loaded machine or a fully automated multi-spindle system. Sunnen system-engineers each SV-500 machine as an optimized processing package, complete with custom guarding, custom risers and fixturing, tooling, abrasives, gaging and coolants, as required by the application. The versatile platform is available with a malleable-iron base or T-slot table just above floor level, or with various workholding and table options at waist height. Part indexing options include in-line shuttles for transfer lines, as well as 2- and 32-position rotary tables or (fourth axis) servo-index table with infinite positioning. The open-base design allows easy pass-through of large parts and makes the machine highly adaptable for parallel manufacturing in a lean environment. Stainless steel guarding all around is maintenance free.

To realize highest unmanned processing efficiencies, the SV-500 can be equipped for in-process air gaging with Sunnen's PH hone head ? or with post-process air gaging. PH tools are designed to produce optimum straightness and roundness with multiple stone configurations. They are available with conventional, diamond or CBN metal-bond abrasives, specifically engineered for a given application. A plug gauge shutoff is also available for processes that do not require the feedback or precision of air gauging. Setup is fast and easy, all handled from the front of the machine without raising a cover. An intuitive interface and advanced PC-based control simplify the honing process to allow anyone with multi-axis experience to run the machine like an expert. The SV-500 Series provides great cost, size and flexibility advantages over hydraulic honing systems of comparable capacities. Vertical design conserves shop floor space.

——————————————————————

www.sunnen.com