PDF Series Pre-fill Valve | PDF-80-20 | PDF-100-20 | PDF-125 | PDF-150 | Hydraulic Surge Valve for Press Machine

PDF Series Stacked Hydraulic Pre-fill Valves (Full Oil Surge Valves)

Product Overview: The PDF series Pre-fill Valves (also known as Full Oil Surge Valves) are indispensable components for large-scale hydraulic machinery, particularly fast-acting presses, injection molding machines, and four-column hydraulic presses. Their primary function is to draw a massive volume of fluid from the oil tank into the main cylinder during the fast-downward (free fall) stroke. Furthermore, they perform a controlled pre-decompression (unloading) before the return stroke begins, preventing violent hydraulic shocks and vibrations. The PDF series features a stacked design, offering a compact structure that significantly enhances the response speed and overall efficiency of hydraulic systems.

Featured models include: PDF-80-20, PDF-100-20, PDF-125-20, and PDF-150-20.

Key Technical Advantages:

• High-Capacity Flow Design: Specially engineered for massive filling rates, minimizing suction resistance and preventing vacuum formation (cavitation) in the main cylinder during high-speed strokes.

• Superior Decompression Characteristics: The built-in pilot decompression logic ensures an extremely smooth pressure release when transitioning from high-pressure to low-pressure, extending the service life of seals and piping.

• High-Pressure Reliability: Constructed from high-strength cast iron or forged steel, with rated operating pressures reaching 25-31.5 MPa.

• Simplified Installation: The classic 20 series design supports standardized stacked mounting, reducing piping space requirements and simplifying maintenance routines.

Detailed Specifications & Parameters:

• Featured Model Matrix:

  • PDF-80-20: Nominal Diameter 80 mm, suitable for medium-to-large presses.

  • PDF-100-20: Nominal Diameter 100 mm, the preferred choice for high-flow filling.

  • PDF-125-20: Nominal Diameter 125 mm, meets the demands of heavy-duty pressing equipment.

  • PDF-150-20: Nominal Diameter 150 mm, ultra-high flow filling capacity.

• Core Technical Specs:

  • Max Operating Pressure: 25 MPa / 31.5 MPa.

  • Control Type: Hydraulic Pilot Operated.

  • Construction Type: Stacked / Manifold Type.

  • Sealing Material: Equipped with high-performance, wear-resistant, and anti-extrusion seals.