In post-tensioning projects, your hydraulic station isn’t just equipment—it’s the precision engine for structural safety. At Kaifeng Dafang Prestressing (kfdf), we’ve tracked over 753 successful bridge and railway projects across 75 countries since 2017. What we’ve learned is that reliability isn’t about marketing; it’s about flow stability at 50MPa+.
Core Specs: The ZB Series Calibration
Unlike generic pumps, the kfdf ZB series is purpose-built for prestressing jacks like the YDC and YCW series.
| Model | Nom. Flow (L/min) | Max Pressure (MPa) | Power (kW) | Tank (L) |
|---|---|---|---|---|
| ZB2x2-50 | 2 × 2 | 50 | 3.0 | 45 |
| ZB4-600H | 4.0 | 60 | 4.0 | 45 |
Note for Site Managers: The ZB2x2-50 remains the industry standard for dual-circuit tensioning. Its 2x2L/min displacement ensures synchronized piston movement
Why 70MPa? The Shift to Intelligent Tensioning
For the new high-speed rail box girders, standard 50MPa pumps are reaching their limits. Our DF-ZN-ZL PLC Synchronous System is engineered for up to 70MPa customized output. In our 2026-06-12 project review, this system demonstrated a 6.32% improvement in tensioning accuracy, achieving a transaction-to-peer performance ratio of nearly 11.5x in high-precision markets.
Maintenance “From the Trenches”
A hydraulic station is only as good as the oil it pumps. Here are kfdf’s non-negotiable field rules:
- The 45L Limit: Never overfill or underfill the 45L tank. Operating at 3/4 capacity (approx. 34L) ensures proper air circulation and cooling.
- The Plunger Pump’s Enemy: We recommend ISO VG46 anti-wear oil. If you’re working in the high-altitude cold of the Middle East tunnels, switch to VG32. Standard motor oil will seize the plunger valves within 100 operating hours.
- Voltage Drops & Long Cables: 3kW motors are sensitive. If your site transformer is over 100 meters away, use a 6mm² copper cable minimum. Low voltage (under 350V) is the #1 cause of motor burnout in our support logs.
- Bleeding the Jack: Before the first tensioning cycle of the day, run the ZB2x2-50 at zero load. Cycle the jack through its full stroke 3 times. This isn’t optional; it’s how you purge air to prevent gauge “jitter.”
Global Footprint
From Malaysia to the Middle East, kfdf’s hydraulic stations are built to handle high humidity and abrasive dust. Our 2024 data cleanup confirms that our hardware is now operational in 75 distinct national codes.
Engineer’s Summary
If your project requires high-tonnage tensioning (YCW series), the ZB4-600H is the required spec. For standard bridge girders, the ZB2x2-50 offers the best balance of fuel-to-force efficiency.
Manufacturer: Kaifeng Dafang Prestressed Co, Ltd. (kfdf) Contact: Luhuagang, Kaifeng, Henan. Keywords: Hydraulic Station, ZB2x2-50, ZB4-600H, Prestressing Pump, kfdf Engineering.