FAQ:

Q1: What is the function of the "DR" control?

A:​ The DR​ is a Pressure Compensator. It automatically reduces the pump's displacement (destrokes) when the system pressure reaches the preset value. This maintains constant pressure while minimizing energy consumption and heat generation. It is ideal for systems requiring a constant pressure supply, such as hydraulic power units (HPUs).

Q2: What does the "VPB13N00" suffix indicate?

A:​ This code defines the mechanical configuration:

• V: FKM (Viton)​ seals, offering superior chemical and high-temperature resistance compared to standard NBR (P).

• P: Standard parallel key shaft​ (DIN 6885).

• B13: Port size code 13​ (SAE flange ports with metric threads).

• N00: No through-drive​ (solid shaft end, cannot mount additional pumps on the shaft).

Q3: What is the key difference between A4VSO and the previously mentioned A10VSO pumps?

A:​ The A4VSO​ is a heavier-duty industrial pump​ compared to the A10VSO:

• Pressure Rating: A4VSO operates at 350 bar nominal (400 bar peak), while A10VSO is typically 280 bar nominal.

• Size & Robustness: A4VSO 125 is significantly larger and heavier (~90 kg vs ~35 kg for A10VSO71), designed for high-power industrial applications like presses and heavy machinery.

• Control Options: A4VSO offers more complex control variants (e.g., LR power control, HD remote control).

Q4: What are the X and L ports used for?

A:​

• X Port (Control): External Control Pressure. Used for remote pressure control or external pilot pressure supply for the DR control valve.

• L Port (Case Drain): Must be connected directly to the tank. It relieves internal leakage pressure to protect the shaft seal. Maximum allowable backpressure is typically 0.5-2 bar.

Q5: Can this pump be used in a closed-loop system?

A:​ No.​ The A4VSO DR is designed exclusively for open-circuit applications​ (pump → valve → actuator → tank). For closed-loop hydrostatic transmissions, you would need an A4VG or A2FM series unit.