| Applicable Wire Diameter |
Fine-wire machines: approximately 0.20–1.00 mm Medium-wire machines: approximately 0.80–3.00 mm Heavy-wire machines: approximately 2.00–6.00 mm |
The machine must cover the complete production range without excessive tooling changes or unstable feeding. |
Request a written wire-diameter range, material compatibility list, and test results using the buyer’s actual wire. |
15% |
| Coil Outside Diameter |
Small precision coils: approximately 3–30 mm General-purpose coils: approximately 10–80 mm Large coils: approximately 30–150 mm |
Maximum and minimum coil diameter affect the forming head, guide system, tooling design, and machine stability. |
Compare the stated diameter range with approved sample drawings, including minimum diameter, maximum diameter, pitch, and free length. |
10% |
| Production Speed |
Fine-wire applications: approximately 30–150 coils/min Medium-wire applications: approximately 15–80 coils/min Heavy-wire applications: approximately 5–30 coils/min |
Rated speed alone can be misleading; usable output must include setup time, inspection, scrap, and stoppages. |
Ask for a factory acceptance test showing sustained output, scrap rate, changeover time, and the exact product configuration. |
15% |
| Forming and Control Capability |
Servo-driven feeding and forming, programmable pitch, adjustable turns, automatic cut-off, and recipe storage are common requirements for flexible production. |
Independent control of feeding, forming, pitch, and cutting improves repeatability across different coil designs. |
Review the machine layout, servo-axis list, control sequence, available recipes, and demonstration of at least three different coil specifications. |
15% |
| Dimensional Accuracy |
A practical target is repeatability within the tolerance stated on the approved product drawing. Common controlled dimensions include coil diameter, pitch, free length, and end geometry. |
Accuracy must be judged against the product tolerance rather than a general marketing claim. |
Require a measurement report based on a statistically meaningful sample, with calibrated instruments and clearly defined inspection points. |
15% |
| Material Compatibility |
The machine should be evaluated with the actual material, such as carbon steel, stainless steel, copper alloy, or other specified wire types. |
Different materials have different hardness, elasticity, surface finish, and springback behavior, which can change forming performance. |
Send production wire samples and request trial coils, process parameters, surface inspection, and a record of wire breakage or scratching. |
10% |
| Automation and In-Line Inspection |
Useful options include automatic wire feeding, straightening, cut-to-length, coil collection, vision inspection, and fault alarms. |
Higher automation can reduce labor requirements and improve consistency, but only when the added systems are properly integrated. |
Confirm the complete process flow, sensor list, rejection method, data-recording capability, and manual intervention points. |
8% |
| Electrical and Safety Compliance |
The machine should have documented risk controls, emergency stops, guarding, electrical drawings, and applicable conformity documentation. IEC 60204-1 is a commonly referenced machinery electrical-safety standard. |
Safety documentation supports installation, operator training, export clearance, and long-term maintenance. |
Request the risk assessment, electrical schematic, safety-circuit description, user manual, and applicable conformity certificates before purchase. |
7% |
| Tooling Changeover |
A well-designed production setup should provide documented changeover procedures, repeatable tooling positions, and stored parameter recipes. |
Short and predictable changeovers are important when producing multiple coil sizes or small batches. |
Measure the complete changeover from the last good part to the first approved part, including tooling adjustment and parameter verification. |
5% |
| Service, Spare Parts, and Warranty |
A clear warranty period, remote troubleshooting process, spare-parts list, maintenance schedule, and response-time commitment should be provided in writing. |
After-sales support directly affects uptime, especially for customized machines and export installations. |
Check the service agreement, spare-parts pricing, software-support policy, training scope, installation method, and escalation process. |
10% |
| Total Cost of Ownership |
Evaluate purchase price together with tooling, freight, installation, training, energy use, consumables, spare parts, maintenance, and expected scrap. |
The lowest initial quotation may have a higher long-term cost if output, accuracy, or service availability is inadequate. |
Request a five-year cost model and compare quotations using the same product samples, output target, tooling scope, and acceptance criteria. |
10% |
| Factory Verification |
The supplier should be able to demonstrate a functioning machine, documented quality procedures, traceable assembly, and completed trials for comparable applications. |
Factory verification reduces the risk of purchasing an unproven design or relying only on catalogue specifications. |
Arrange a live video or on-site audit covering assembly, testing, quality control, machine records, and production of the buyer’s own samples. |
10% |