| Control System | Number of controlled axes | Common configurations range from 4 to 12 axes; more complex wire forms may require additional independent axes. | Independent control of feed, coiling, pitch, cutting, and auxiliary tooling improves the machine’s ability to produce variable-pitch and shaped springs. | Match the required axes to the most complex part in the production schedule, not only to the current standard spring. | High |
| Control System | Programming and data storage | Look for graphical parameter entry, recipe storage, revision control, and the ability to back up programs through a standard data connection. | Clear programming reduces setup errors and makes repeat orders easier to reproduce. | Ask for a live demonstration of creating, editing, saving, backing up, and restoring a spring program. | High |
| Control System | Motion synchronization | Servo-driven axes should provide coordinated electronic motion with adjustable speed and acceleration profiles. | Synchronized motion supports consistent pitch, diameter, end geometry, and cut-off timing at production speed. | Run a sample program containing different pitches, coils, and end treatments rather than testing only a simple compression spring. | High |
| Control System | Operator interface | A color touch interface with alarms, parameter guidance, access levels, and multilingual support is generally preferable. | Good interface design shortens training time and helps operators identify setup or maintenance problems quickly. | Check whether common adjustments can be made without editing low-level motion parameters. | Medium |
| Control System | Quality monitoring | Useful functions include real-time fault alarms, production counters, cycle-time records, and trend monitoring for critical dimensions. | Process information helps detect tool wear, material variation, and drift before a large batch becomes nonconforming. | Confirm which process values are recorded, how long they are retained, and whether data can be exported for quality documentation. | High |
| Wire Capability | Wire diameter range | Select a range that covers the intended material and diameter mix; many general-purpose machines are configured for small- to medium-diameter wire. | Wire diameter affects required feed force, tooling strength, cutter capacity, spring index, and achievable production speed. | Compare the actual minimum and maximum diameters for your materials, including coated, stainless, or high-carbon wire where applicable. | High |
| Tooling | Tool-change method | Quick-change holders, repeatable tool locations, and clearly documented setup references reduce changeover time. | Tooling changes can consume significant production time when many spring families are manufactured in small batches. | Measure a complete changeover using a representative job and include calibration, trial pieces, and first-article approval. | High |
| Tooling | Tool material and wear resistance | Cutters, coiling points, guides, and pitch tools should be selected for the wire material, hardness, surface finish, and production volume. | Tool wear can change spring dimensions, increase burrs, and create unplanned interruptions. | Request expected wear indicators, recommended replacement intervals, sharpening procedures, and critical spare-part lead times. | High |
| Tooling | Tool adjustment range | Verify the available adjustment for coiling points, guides, cutters, pitch tools, and end-forming attachments. | A wide adjustment range allows one machine platform to support more spring geometries without custom mechanical modifications. | Compare the tooling layout against drawings for the largest, smallest, longest, and most complex parts. | High |
| Automation | Automatic wire straightening and feeding | Look for controlled straightening, stable feed tension, anti-slip rollers, and overload detection. | Consistent wire presentation is essential for repeatable diameter, pitch, and end position. | Test the machine with the actual wire sizes and surface conditions used in production. | High |
| Automation | Automatic cut-off and end forming | Available functions may include programmable cut-off, closed or open ends, reduced ends, hooks, loops, and special bends. | Integrated forming reduces secondary operations, handling, and the risk of dimensional variation between processes. | Confirm that the required end geometry can be produced in one setup and inspect cut quality on finished samples. | High |
| Automation | In-process inspection | Options may include laser measurement, camera inspection, force checks, length checks, and automatic rejection of out-of-tolerance parts. | Automated inspection reduces dependence on manual sampling and supports stable production of safety-critical components. | Define the critical-to-quality dimensions, measurement tolerance, inspection frequency, and reject-handling method. | Medium |
| Automation | Material handling and collection | Consider controlled part discharge, conveyors, collection bins, separators, and automatic counting. | Careful handling prevents tangling, surface damage, and mixed lots while reducing operator intervention. | Check whether finished parts can be collected without damaging hooks, coils, coatings, or formed ends. | Medium |
| Performance | Production speed versus usable output | Evaluate parts per minute under real operating conditions rather than relying only on an unloaded maximum cycle rate. | Setup time, inspection, material loading, tool wear, and rejects determine effective capacity. | Calculate output using a representative job, including changeover, trial pieces, downtime, and quality losses. | High |
| Performance | Dimensional repeatability | Require documented repeatability data for length, outside diameter, pitch, end angle, and other critical dimensions. | Repeatability is more useful than headline speed when springs must meet tight functional or assembly requirements. | Run multiple batches after a setup change and compare measurements using the same inspection method used in your facility. | High |
| Maintenance | Access and preventive maintenance | Prioritize accessible lubrication points, guarded service areas, diagnostic messages, and documented maintenance intervals. | Simple maintenance improves uptime and reduces the risk of premature wear in feed, tooling, and motion components. | Request the maintenance schedule, lubrication specifications, service access requirements, and recommended spare-parts list. | Medium |
| Safety | Guarding and safety functions | Verify fixed guards, interlocked access doors, emergency stops, safe restart behavior, and protection from wire and tooling hazards. | High-speed wire and moving forming tools can create serious mechanical hazards if access is not controlled. | Review the machine risk assessment and confirm compliance with the safety requirements applicable to the installation location. | High |
| Integration | Connectivity and production reporting | Useful options include standard industrial network communication, remote diagnostics, recipe transfer, and production-data export. | Connectivity supports traceability, maintenance planning, and integration with manufacturing or quality systems. | Confirm supported protocols, cybersecurity controls, data ownership, and whether connectivity requires additional hardware or software. | Medium |
| Total Cost | Lifecycle cost | Include machine price, tooling, installation, training, energy, consumables, maintenance, software, inspection equipment, and downtime. | The lowest purchase price may not provide the lowest cost per acceptable spring over the machine’s operating life. | Compare cost per good part and expected payback using realistic utilization, labor, scrap, maintenance, and changeover assumptions. | High |