JAW-1000 Computer-Controlled Manhole Cover Compression Testing Machine

System Components

A．Main Machine Frame

Consists of upper/lower crossheads, columns, hydraulic assembly, working platform, load cell, and residual deformation measuring device. It adopts a dual-space portal frame structure formed by the crossheads and columns. Compression testing is performed via vertical movement of the cylinder.

· Crossheads:

· Fabricated using welded No. 45 alloy steel, precision-machined via CNC to ensure dimensional and geometric accuracy for coaxial alignment and parallelism. Finished with sandblasting, primer, and top-coat treatment.

· Columns:

· Made of surface-hardened chrome-plated alloy steel shafts, CNC machined to ensure overall rigidity and reduce external influences on testing precision.

· Hydraulic Assembly:

· The cylinder uses high-performance seals with wear-resistant cylinder and piston materials. High-pressure flexible hoses ensure precise motion with no leakage.

· Load Cell:

· Self-developed spoke-type pressure load cell optimized for compression testing; features minimal drift, high sensitivity, imported strain gauges, and nickel plating.

· Residual Deformation Gauge:

· Uses digital grating ruler with 0.01 mm resolution for highly accurate measurement of specimen deformation.

B．Hydraulic Power Source

The high-pressure section utilizes a state-of-the-art intelligent servo hydraulic system, including a branded motor, Italian Marzocchi pump, digital servo valve, follower valve, and directional control valve, ensuring reliable operation.

C．Fixtures & Accessories

Includes a set of rigid pads specifically designed for manhole cover testing.

D．Electrical Measurement & Control System

· Stable and reliable operation with overload, overcurrent, overspeed, overvoltage, and limit protection.

· Integrated 32-bit high-speed ARM processor for data acquisition, PID computation, communication, and closed-loop control.

· Supports remote firmware upgrade and custom functions.

Input Channels:

· One high-precision 24-bit A/D conversion channel, 50 Hz sampling, effective resolution 1/500,000, digital gain adjustment, multi-point sensor calibration.

· One quadrature encoder digital input and 10M/Bit optocoupled input for differential cable encoder.

· Eight digital input ports configurable for limits, emergency stop, or external control.

Output Channels:

· One PWM output (50 Hz base frequency configurable)

· One PWM-H high-level output with adjustable dither frequency and amplitude (50–1000 Hz, 5–40% Vpp)

· Eight DO outputs (24V, 1A), directly driving relays or solenoid valves.

Communication Interfaces:

· USB 2.0 for high-speed PC/laptop connection, industrial-grade EMI protection, compatible with all Windows OS

· Wi-Fi (802.11 b/g/n) for direct tablet connectivity (e.g., Windows 10)

· Industrial Ethernet (10/100 Mbps)

· Industrial RS485 (MODBUS and HMI support)

Data Storage:

Test control parameters are automatically saved in the controller and remain unaffected by PC changes.

Other Features:

· Manual or automatic fast return to starting position after testing

· True physical zeroing, gain adjustment, automatic range switching, calibration, and storage for test force—no analog circuits

· Electrical circuits comply with international and national testing machine standards, with strong anti-interference capability ensuring accuracy

· Built-in networking for data storage, transmission, printing, and LAN/Internet connectivity

E. Operation Software

· The control and measurement software features a beautiful interface, powerful functions, and easy operation, fully supporting multi-language switching under Windows XP/7/8/10/11 operating systems.

· The software records in real time and dynamically displays test curves such as force-time and displacement-time, supports multi-graph display, and allows switching between views at any time.

· It uses human-machine interaction to analyze and calculate mechanical performance indicators of tested materials. At the end of the test, it can automatically calculate elastic modulus, yield strength, non-proportional elongation stress, etc. (analysis data vary depending on test method). On the basis of automatic analysis, manual correction of analysis results is also supported to improve accuracy.

· The software can realize multi-axis control: one set of software can coordinate multi-axis loading.

· A standard database manages test data, automatically saves test data and curves, and provides network data interfaces.

· The software provides users with multiple report printing interfaces and templates; users can also edit and print reports in Excel format, and batch printing of reports is supported.

· The software allows setting test force over-range protection measures, ensuring a safe test environment for users.