Survival of the Fittest

Various market factors and economic conditions have made retrofitting existing machine tools a very viable option for the large metalworking department at an OEM, as well as the job shop sector of moldmakers, tool and die, and contract part manufacturers alike. Today’s business climate has combined with economic factors involved in the manufacture of control packages to create an ideal atmosphere for retrofit.

For example, we have long been involved in the upgrade of giant gantry mills for aerospace production. But today, it’s just as likely to find our Retrofit Solution Partners outfitting a 3-axis mill or even a basic lathe with a new entry-level or mid-range CNC, motor and drive package. And the best news of all for the job shop is that this work can now be done at a price point comparable to the cost of just the CNC a decade ago, owing to economies of scale in the manufacture of these control packages.

The typical tipping point on a retrofit job is 60 percent of the price of a new machine. However, many machines have outdated controls, although they still perform adequately in the shop or production department. The challenge, when doing an onsite machine evaluation, is to determine whether a retrofit will make an appreciable difference in the performance of the machine, as other factors in the mechanics of the iron might make a retrofit impractical. Today’s control technology is evolving at a very rapid rate, making some equipment that went out of production just ten years ago less than optimum in contributing to maximum machine tool performance. Running machine tools with 20-year-old technology today will not keep a shop as competitive as it needs to be.

Having worked with machine tools for decades, I have had my share of experiences with “old iron” in the field. A lot of people think their old iron is just impossible to keep running, even with a retrofit, but quite often old equipment can actually be made to run better than it did when it was new. This is achieved through faster control processors, improved motor and drive technology, even more accurate and responsive encoders and other machine status sensing devices. You cannot, however, fix a broken leg with a bandage, so the machine evaluation needs to be very comprehensive.

At the end of the day, both the large OEM production department and the job shop alike need to have regular assessments done on their prototype and production machine tools to determine if a retrofit might be in order. The savings can be substantial compared to new machines because it’s not just a matter of the dollars saved at the outset, it’s also the long-term production improvements that inevitably lead to even greater profit for the job shop or OEM. For this reason, selecting an experienced retrofit service supplier with a proven track record is important in order to match the capabilities required to the specific needs for each job.

For example, we currently have 17 Retrofit Solution Partner companies under contract in the U.S. that have undergone a meticulous process of evaluation by the manufacturer, who provides the equipment for installation and then backs it with a full warranty. These partner firms for our Machine Tool Business must have a demonstrated ability to work on CNC, PLC, servo motor, digital drive and all accompanying peripheral products, plus have a proficiency in the development of software packages related to PLC and CNC applications. Every Solution Partner commits to a battery of training sessions and is required to keep at least two Siemens-trained engineers on staff at all times.

These Solution Partners are not geographic specific because some have proven expertise in the field working on particular types or brands of machine tools. The selection process for the appropriate partner takes many factors into consideration. We have partners who specialize in 5-axis work, others who have expertise in a certain industry and still others who have their greatest strength in a particular area of the country. Depending on the job specifics and the logistic costs involved, much effort is placed into matching the right partner to the customer’s needs.

Tom Curfiss is the retrofit business development manager for Siemens Industry, Inc., 4620 Forest Avenue, Cincinnati, OH 45212, 513-841-3100, [email protected], www.usa.siemens.com/cnc. 

EVALUATE MACHINE TOOL CAPABILITY AND CONDITION IN LESS THAN THREE HOURS
Ideal for pre-purchase equipment inspection or a run of critical parts, the new ProCheck machinery evaluation from Fives Global Services (Hebron, KY) covers eight critical areas, from axis kinematics and positioning to bearing vibration and coolant condition. ProCheck provides a detailed report on the condition and capability of machine tools and other major plant equipment prior to purchasing or using systems for critical manufacturing. “Predictive maintenance inspections with this service helps avert unscheduled downtime and reduce scrap by ensuring machine tool capability before running critical parts,” explains Gary Finney, the vice president and general manager of Fives Global Services. “A ProCheck inspection takes less than three hours and includes a detailed report, all for $600 per machine.”

A ProCheck inspection for machine tools begins with a 3-axis ballbar test that evaluates 11 areas including circularity, squareness, backlash, axis reversal spikes and straightness. Other tests include:

• Measurement of spindle clamping force and runout.
• Ultrasonic scanning of critical plant/machine systems for bearing vibration/noise, air leaks, pump cavitation, and electrical anomalies.
• Infrared thermographic inspection of bearings, motors, pumps and electrical systems.
• Refractometer testing of coolant condition, concentration and pH level, as well as measurement of tramp oils.
• Ground loop and current leakage testing of electrical systems.

According to Mel Gay, the manager of technology solutions at Fives, the ProCheck package of services is unique in its scope and low cost. “A ballbar check alone can cost $1000 from an outside contractor, but ProCheck includes inspection of multiple machine systems, with a variety of appropriate tools, by a person trained in using those tools,” he said. “As a builder of large machining systems, we have a unique background in managing the ‘health’ of complex equipment, and this offers that capability to the industry for a nominal cost.”

Fives Global Services, 2200 Litton Lane, Hebron, KY 41048, 859-534-4600, www.fivesgroup.com.

MEASURE AND INTERPRET SPINDLE OPERATING DATA FOR EARLY DETECTION OF PROBLEMS
The Spindle Assessment Kit from SKF USA, Inc. (Lansdale, PA) provides an easy way to measure and interpret key spindle operating data to help shops detect developing problems before they can escalate.  Designed for use after a spindle is assembled and installed in a machine tool, the kit can help OEMs or quality control staff to validate performance indicators, including vibration, thermal behavior, running accuracy, and natural frequency, among others. The kit also can detect spindle unbalance conditions and assist in understanding resonance frequency, which is essential to cutting quality. It ultimately delivers cost-effective condition monitoring technology to help avoid spindle downtime and increase machine tool uptime.

The Spindle Assessment Kit includes three programs: spindle test module, balancing module (for fine tuning) and RUCD (Run Up Coast Down) module (to test resonance frequency). The spindle test module provides nine condition tests: imbalance and balancing (vibration), bearing condition (vibration), mechanical condition (vibration), resonance frequency, speed accuracy, belt tension, tool nose run out, EM distance, and clamp force.

The complete kit consists of a portable Microlog Analyzer, acceleration sensor, laser tachometer, dial gauge with gauge stand, belt tension gauge, and a spindle-specific software package preconfigured to convert measured data into intuitive green-amber-red (“traffic light”) color-coded results. The user-friendly kit provides step-by-step instructions and features lightweight ergonomic design, extended battery life, easy operation function keys, and rugged and water-resistant design. Automatic analysis of spindle condition will indicate possible faults, imbalance, and bearing defects, among other operating problems.

This kit expands an extensive portfolio of SKF spindle services (from repairs and remanufacturing to upgrades) for optimized machine tool maintenance strategies.

SKF USA Inc., 890 Forty Foot Road, PO Box 352, Lansdale, PA 19446, 888-753-3477, www.skfusa.com.

EXTENSIVE LINE OF NEW SPINDLES
Gilman Precision, Inc. (Grafton, WI) is proud to announce a newly designed catalog displaying their extensive line of spindles. Last updated in 2005, the company has greatly improved the ease of spindle selection, along with combining all previous spindle catalogs, creating a one-stop resource. “We are in the process of upgrading our current catalogs and idea bulletins. We have a lot to offer when it comes to our products and services, so it’s crucial that they are presented in the best possible fashion,” said Douglas Biggs, the vice president of sales and marketing at Gilman.

The new catalog discusses spindle systems and selections, products features, ordering instructions, and an in-depth look at spindle quality. The products included are eight different series of belt-driven spindles, Mech-Tronix integrally motorized spindles, and standard spindle accessories. “We took our time on this. We want our catalog to present clear and precise information to the customer,” said Chris Hetzer, the chief executive officer of Gilman Precision. “This is especially important for our online version of the catalog — easy navigation and organized material. This catalog also provides a great starting point for those customers desiring a custom spindle.” Available in print and electronically, contact the company today for a specially mailed spindle product catalog at 800-445-6267 or visit them online.

Gilman Precision, 1230 Cheyenne Avenue, Grafton, WI 53024, 262-377-2434, Fax: 262-377-9438, www.gilmanprecison.com.