2520VQ21A14-86AA22R Vickers Double Vane Pump 67.5 cc

Product Overview

The 2520VQ21A14-86AA22R is a Vickers by Danfoss VQ Series double fixed-displacement intravane vane pump designed for high-flow industrial hydraulic applications.

Danfoss’s official VQ documentation covers 2520VQ, 3520VQ, 4520VQ and 4535VQ double-pump configurations and provides detailed displacement, pressure, speed, shaft, port-orientation and installation data.

For the exact 2520VQ21A14-86AA22R, Danfoss PowerSource confirms:

• 2520VQ: 2520VQ double pump
• 21: 21 USgpm shaft-end section
• A: SAE 4-bolt flange inlet and outlet connections
• 14: 14 USgpm cover-end section
• 86: heavy-duty straight keyed shaft with 1/4-in square key
• AA: Outlet 1 opposite the inlet; Outlet 2 135° counterclockwise from the inlet
• 22: Design 22
• R: Clockwise rotation viewed from shaft end.

The official displacement table specifies 67.5 cm³/rev for the 2520VQ21 section and 45.9 cm³/rev for the 2520VQ14 section.

Importantly, the two sections do not share exactly the same operating limits. The 21-GPM shaft-end section is rated to 210 bar and 2500 r/min, while the 14-GPM cover-end section is rated to 140 bar and 2700 r/min.

Therefore, pressure, speed, flow and input-torque calculations must be performed separately for each section.

Technical Specifications

Primary Model: 2520VQ21A14-86AA22R

• Brand: Vickers by Danfoss
• Series: VQ Series
• Model: 2520VQ21A14-86AA22R
• Pump Type: Double fixed-displacement intravane vane pump
• Frame Size: 2520VQ
• Shaft-End Displacement Code: 21
• Shaft-End Geometric Displacement: 67.5 cm³/rev
• Shaft-End Maximum Working Pressure: 210 bar (3000 psi)
• Shaft-End Maximum Speed: 2500 r/min
• Cover-End Displacement Code: 14
• Cover-End Geometric Displacement: 45.9 cm³/rev
• Cover-End Maximum Working Pressure: 140 bar (2000 psi)
• Cover-End Maximum Speed: 2700 r/min
• Combined Geometric Displacement: 113.4 cm³/rev
• Control Method: Fixed displacement
• Mounting: Flange mount
• Port Connection: A — SAE 4-bolt flange
• Shaft: 86 — heavy-duty straight keyed
• Key: 1/4-in square key
• Port Orientation: AA — Outlet 1 opposite inlet; Outlet 2 135° CCW from inlet
• Design: 22
• Rotation: R — clockwise
• Height: 146.05 mm
• Length: 336.30 mm
• Width: 174.75 mm
• Approximate Weight: 20.5 kg.

Theoretical Flow Reference

Using the published geometric displacements:

• Shaft-end section at 2500 r/min: approximately 168.75 L/min
• Cover-end section at 2700 r/min: approximately 123.93 L/min
• Combined theoretical flow at a common 2500 r/min: approximately 283.5 L/min

These are geometric theoretical values before volumetric losses and should not be treated as guaranteed delivered flow.

Related Model: 3520VQ35A11 1AD20

The second supplied model is also a Vickers by Danfoss VQ Series double pump. Danfoss PowerSource directly lists 3520VQ35A11 1AD20 as a 3520VQ double pump.

The official model-code system defines:

• 3520VQ: 3520VQ double pump
• 35: Shaft-end 35 USgpm capacity
• A: SAE flange port configuration
• 11: Cover-end 11 USgpm capacity
• 1: Straight keyed shaft
• AD: Outlet 1 opposite inlet; Outlet 2 135° clockwise from inlet
• 20: Design 20
• No L suffix: Right-hand / clockwise rotation.

The official displacement table specifies:

• 3520VQ35: 112.8 cm³/rev
• 3520VQ11: 36.4 cm³/rev.

3520VQ35A11 1AD20 Specifications

• Model: 3520VQ35A11 1AD20
• Pump Type: Double fixed-displacement intravane vane pump
• Shaft-End Geometric Displacement: 112.8 cm³/rev
• Shaft-End Maximum Working Pressure: 210 bar
• Shaft-End Maximum Speed: 2400 r/min
• Cover-End Geometric Displacement: 36.4 cm³/rev
• Cover-End Maximum Working Pressure: 210 bar
• Cover-End Maximum Speed: 2500 r/min
• Combined Geometric Displacement: 149.2 cm³/rev
• Shaft: 1 — straight keyed
• Port Orientation: AD — Outlet 1 opposite inlet; Outlet 2 135° CW from inlet
• Rotation: Right-hand / clockwise
• Design: 20
• Height: 162.81 mm
• Length: 349.76 mm
• Width: 212.85 mm
• Approximate 3520VQ double-pump weight: 34.0 kg.

An important engineering distinction is that the 35-GPM shaft-end section is limited to 2400 r/min, not 2500 r/min, while the 11-GPM cover-end section is rated at 2500 r/min.

Key Technical Advantages

1. Double Intravane Architecture

The VQ Series uses intravane pump technology and integrates two pump sections into one mechanical package.

This allows two hydraulic outputs to be driven from a common input shaft, making the architecture useful for multi-circuit industrial hydraulic systems.

2. Different Sections for Different Hydraulic Duties

For 2520VQ21A14-86AA22R:

P1 = 67.5 cm³/rev
P2 = 45.9 cm³/rev

Their operating envelopes are different:

P1: 210 bar / 2500 r/min
P2: 140 bar / 2700 r/min.

This allows the two sections to be allocated according to the pressure and flow requirements of separate hydraulic circuits.

3. High-Flow Industrial Capacity

For 3520VQ35A11 1AD20:

P1 = 112.8 cm³/rev
P2 = 36.4 cm³/rev

At their respective maximum speeds, theoretical geometric flows are approximately:

• P1: 270.72 L/min
• P2: 91.00 L/min

These are calculated geometric values rather than guaranteed delivered flow.

4. Standard SAE Flange Interfaces

The official VQ coding system defines A as the SAE 4-bolt flange configuration. Danfoss PowerSource directly confirms the 2520VQ21A14 configuration with four-bolt flange connections for the inlet and both outlets.

5. Precisely Defined Port Orientation

For 2520VQ21A14-86AA22R:

AA = Outlet 1 opposite inlet + Outlet 2 135° CCW

For 3520VQ35A11 1AD20:

AD = Outlet 1 opposite inlet + Outlet 2 135° CW

This difference is highly relevant to piping and retrofit work.

6. Heavy-Duty 86 Shaft

The 86 shaft used in the 2520VQ21A14 configuration is defined by Danfoss as a heavy-duty straight keyed shaft with a 1/4-in square key.

The drive coupling must nevertheless be selected according to the actual shaft torque and alignment requirements.

7. Established VQ Service Documentation

The official Vickers by Danfoss VQ design guide provides:

• Model codes
• Operating specifications
• Installation dimensions
• Optional shafts
• Performance curves
• Shaft torque data

This supports engineering-level replacement rather than appearance-based substitution.

Application Areas

Danfoss’s official VQ documentation identifies applications including:

• Plastics machinery
• Press machines
• Die casting
• Machine tools
• Test equipment
• Primary metals
• Pulp and paper
• Wood processing
• Oil and gas
• Marine
• General industrial equipment.

The 2520VQ and 3520VQ double-pump configurations are particularly suitable for:

• Industrial hydraulic power units
• Press machines
• Injection molding equipment
• Die-casting machinery
• Metal-forming equipment
• Material handling systems
• Primary-metal processing
• Multi-circuit hydraulic systems

Expert Maintenance Tips

1. Calculate Each Pump Section Independently

The 2520VQ21A14-86AA22R should not simply be described as a “210-bar / 2700-r/min double pump.”

The correct engineering interpretation is:

P1: 67.5 cm³/rev / 210 bar / 2500 r/min
P2: 45.9 cm³/rev / 140 bar / 2700 r/min.

Likewise, 3520VQ35A11 is:

P1: 112.8 cm³/rev / 210 bar / 2400 r/min
P2: 36.4 cm³/rev / 210 bar / 2500 r/min.

2. Verify Combined Shaft Torque

Danfoss explicitly warns that double, triple and thru-drive pump assemblies cannot automatically be assumed to operate all sections simultaneously at rated pressure.

Check:

P1 Torque + P2 Torque ≤ Shaft Torque Limit.

This is especially important for the large-displacement 3520VQ35A11 configuration.

3. Verify the Shaft Configuration

The supplied models use different shaft configurations:

• 2520VQ21A14-86AA22R: 86 = heavy-duty straight keyed
• 3520VQ35A11 1AD20: 1 = straight keyed.

The coupling therefore should not be assumed interchangeable simply because both pumps belong to the same VQ family.

4. Verify Port Orientation

Before replacing either unit, confirm:

2520VQ → AA
3520VQ → AD

A port-orientation mismatch can require substantial hydraulic piping changes.

5. Protect the Suction Circuit

Danfoss recommends:

• Short suction lines
• Large internal diameters
• Minimal bends and fittings
• No reduction below specified nominal port sizes
• Protection against excessive inlet vacuum
• Prevention of air ingress.

This becomes particularly important for the large-flow 3520VQ35 section.

6. Control Cold-Start Conditions

Danfoss notes that cold starts can create vacuum at the pump inlet because fluid viscosity increases. Avoid high-speed operation until the system has warmed and positive inlet supply pressure is actually present.

7. Maintain Shaft Alignment

Danfoss states that shaft concentricity and angular alignment directly affect pump life. Misalignment can impose heavy bearing loads and lead to premature failure.

Check:

Motor Shaft → Coupling → Pump Shaft

during installation.

8. Avoid Extended High-Pressure Operation at Idle

The official guide warns against operating the pump at or near rated pressure at idle speed for extended periods because localized overheating and damage can result.

9. Maintain Hydraulic-Fluid Cleanliness

The official VQ guide identifies fluid cleanliness, correct viscosity, additive compatibility and prevention of aeration as important factors in component life.