ZTH Series Four-Station Spring Fatigue Testing Machine by SINOTEST
| Brand | SINOTEST |
|---|---|
| Origin | Jilin, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | ZTH Series |
| Pricing | Available Upon Request |
Overview
The ZTH Series Four-Station Spring Fatigue Testing Machine is an electromechanically driven, multi-axis fatigue test system engineered for high-reliability cyclic loading of automotive suspension springs under controlled amplitude and frequency conditions. It operates on the principle of mechanical resonance excitation via a centrally located eccentric linkage mechanism, which converts rotary motion from a servo motor into precise sinusoidal vertical displacement across four independent test stations. The cruciform (cross-shaped) station layout—featuring two pairs of diametrically opposed spring fixtures—enables symmetrical load application and energy recovery during the unloading phase, significantly improving mechanical efficiency and reducing net power consumption compared to single-station configurations. Designed specifically to meet OEM and Tier-1 supplier requirements for durability validation, this system supports accelerated life testing in accordance with ISO 10243, SAE J1507, and GB/T 25916 (Chinese national standard for automotive coil spring fatigue testing).
Key Features
- Four independent test stations arranged in a rigid cruciform frame, enabling concurrent fatigue evaluation of up to four identical or matched springs.
- Eccentric linkage mechanism at the geometric center allows continuous, tool-free adjustment of stroke amplitude (typically 1–20 mm range, configurable per application), ensuring compliance with diverse OEM specification envelopes.
- Bi-directional energy recovery architecture: opposing spring pairs operate in counter-phase, allowing elastic energy stored during compression to assist in tension recovery—reducing effective motor torque demand by up to 35% versus conventional unidirectional setups.
- Integrated load cell and displacement transducer at each station provide real-time force-displacement hysteresis monitoring, supporting stiffness degradation tracking and cycle-by-cycle parameter logging.
- Heavy-duty cast-iron base and reinforced steel crosshead ensure minimal frame deflection (< 2 µm under maximum rated load), preserving test repeatability and alignment integrity over extended duty cycles.
- IP54-rated electrical cabinet with industrial-grade PLC control, emergency stop circuitry compliant with ISO 13850, and dual-channel safety relays for motion interlock.
Sample Compatibility & Compliance
The ZTH machine accommodates cylindrical coil springs with free heights ranging from 100 mm to 600 mm and wire diameters from 4 mm to 22 mm. Fixtures support both seated and non-seated configurations with adjustable preload clamps and parallelism compensation plates. All mechanical interfaces comply with DIN 2092 (spring design standards) and ASTM E466 (standard practice for conducting force-controlled constant amplitude axial fatigue tests). System documentation includes full traceability of calibration certificates for load cells (ISO/IEC 17025 accredited) and displacement sensors (NIST-traceable). The machine meets CE machinery directive 2006/42/EC and is designed for integration into GLP-compliant laboratory environments with optional audit trail and electronic signature modules.
Software & Data Management
Control and data acquisition are managed via SINOTEST’s proprietary TestMaster-Fatigue software platform, running on a Windows-based industrial PC with real-time Windows OS extension (IntervalZero RTX64). The software provides synchronized control of all four stations—including independent frequency tuning (0.5–15 Hz range), programmable waveform profiles (sine, trapezoidal, custom harmonic superposition), and automatic termination criteria (e.g., stiffness drop >12%, cycle count, or force deviation >±5% of nominal). Raw data streams (force, displacement, temperature, cycle count) are logged at ≥1 kHz sampling rate and exported in ASTM E1437-compliant .tdms or .csv formats. Optional FDA 21 CFR Part 11 compliance package includes role-based user authentication, electronic signatures, immutable audit trails, and encrypted database storage.
Applications
- Durability validation of front/rear suspension coil springs for passenger vehicles, commercial trucks, and off-road platforms.
- Comparative fatigue performance assessment of alternative spring materials (e.g., chrome-silicon vs. patented low-alloy steels) under variable temperature and humidity conditions.
- Verification of spring design modifications—such as pitch variation, end configuration, or shot-peening intensity—against target service life (e.g., 200,000–500,000 cycles).
- Root cause analysis of field failures through correlation of lab-induced crack initiation sites (via post-test micro-CT scanning) with measured hysteresis loop evolution.
- Supporting APQP Stage 3 (Production Part Approval Process) submissions with statistically valid Weibull-based life distribution modeling.
FAQ
What is the maximum allowable test frequency per station?
The system supports a nominal operating frequency range of 0.5 Hz to 15 Hz, with stability and thermal management optimized for continuous operation at 10 Hz for ≥72 hours.
Can the machine perform progressive amplitude testing (e.g., stepwise increase in stroke)?
Yes—TestMaster-Fatigue software supports multi-step amplitude ramping protocols, including linear, logarithmic, or user-defined step sequences with dwell time and pass/fail logic per step.
Is third-party calibration certification included with delivery?
Each unit ships with factory calibration reports for all transducers; optional ISO/IEC 17025-accredited field calibration services are available upon request.
Does the system support remote monitoring and diagnostics?
Standard Ethernet/IP connectivity enables OPC UA-based integration with MES or SCADA systems; remote desktop access for troubleshooting is supported under IT-approved secure tunneling protocols.
What maintenance intervals are recommended for the eccentric linkage mechanism?
Lubrication of the eccentric bearing assembly is required every 500 operational hours; full inspection and backlash verification are scheduled at 2,000-hour intervals per preventive maintenance manual.
