The name is the two section sizes
Before any code reading, the model name already says what the pump is: 2520V is a 25V section at the shaft end combined with a 20V section at the cover end. The digits are read as two pairs, the two sections may differ, and that is why the family runs 2520V, 3520V, 3525V, 4520V, 4525V and 4535V rather than a single number.
A V double pump carries two cartridge sections on one shaft inside a single housing: one inlet and two independent outlets, so two circuits can run at different pressures and flows from one drive. The shaft-end section is the larger of the pair; the cover-end section takes its place on the same shaft. Both sections are cartridge type, so a worn pump is reconditioned by replacing the cartridges rather than the complete unit, and the housing and shaft stay on the machine.
The line is built on the V vane family (172 bar class), so the two sections in one pump share the family while the two sizes in the frame number can differ. The frame combinations are 2520V, 3520V, 3525V, 4520V, 4525V and 4535V.
How the combination is named
The frame number is read as two pairs of digits: the first pair is the shaft-end section size and the second pair the cover-end section size. 2520V is therefore a 25V section at the shaft end with a 20V section at the cover end.
| Frame | Shaft-end section | Cover-end section |
|---|---|---|
| 2520V | 25V | 20V |
| 2525V | 25V | 25V |
| 3520V | 35V | 20V |
| 3525V | 35V | 25V |
| 4520V | 45V | 20V |
| 4525V | 45V | 25V |
| 4535V | 45V | 35V |
In every combination listed above the shaft-end section is the larger of the two, and the pair is written largest first. The frame number fixes which section sits at the shaft end; the cover-end cartridge mounts on its own bore and carries its own bearing arrangement.
The 13 code positions
A V double pump is ordered through 13 positions. Compared with the 12-position code of a V single pump, the cover-end displacement is inserted at position 7, so mounting, shaft, outlet position, design number and rotation move back by one place. A position is omitted when the standard value applies, and an omitted position does not shift those that follow.
| # | Position | Values |
|---|---|---|
| 1 | Seals | F3 for phosphate-ester and fire-resistant fluids; omitted for mineral oil |
| 2 | Series | 2520V · 3520V · 3525V · 4520V · 4525V · 4535V |
| 3 | Pilot | Omitted = standard; S = SAE; M = metric |
| 4 | Shaft-end displacement | Code from the displacement table, read on the shaft-end size |
| 5 | Port | A = SAE 4-bolt flange — the only option on doubles |
| 6 | Port modifier | Omitted = inch threaded fasteners; M = metric |
| 7 | Cover-end displacement | Code from the displacement table, read on the cover-end size |
| 8 | Mounting | Omitted = flange; F = foot |
| 9 | Shaft | Shaft table below |
| 10 | Outlet position | Two letters, one per outlet, read from the cover end |
| 11 | Design number | 22 |
| 12 | Rotation | L or R; omitted means right-hand |
| 13 | Special suffix | Omitted means none — 167 denotes a 2-bolt 5.00 in pilot |
The string is written in groups rather than as a continuous sequence, so 2520V12A11 11DD22R and 2520V 12 A 11 – 11 DD 22 R denote the same pump.
Positions 4 and 7: the two displacement codes
The two digits in the frame number are sizes; the displacement of each section is set separately by its own code, so the same frame can be ordered with many combinations of flow. Read position 4 against the shaft-end size and position 7 against the cover-end size.
| Code | 20V | 25V | 35V | 45V |
|---|---|---|---|---|
| Displacement (cm³/r) | 2 = 7 5 = 18 8 = 27 9 = 30 11 = 36 12 = 40 14 = 45 |
10 = 33 12 = 40 14 = 45 17 = 55 21 = 67 |
25 = 81 30 = 97 35 = 112 38 = 121 |
42 = 138 45 = 147 50 = 162 60 = 193 |
One figure differs between double and single pump tables: on a 25V section, code 12 is 40 cm³/r in a double pump and 39 cm³/r on a single. Match the nameplate rather than the table to hand.
The digits are the SAE rated capacity in US gpm at 1200 r/min and 7 bar, not a geometric sequence, so a code means a different displacement on each size: 14 is 45 cm³/r on both 20V and 25V, while 25 is 81 cm³/r on the 35V.
Pressure comes from the section and the code
| Section | Maximum continuous pressure |
|---|---|
| 20V in a V double | 207 bar on codes 5, 8 and 11; 159 bar on code 12; 138 bar on codes 2 and 14 |
| 25V · 35V · 45V in a V double | 172 bar on every displacement code |
Each section has its own limit, and the two outlets can be valued independently, so size each circuit to the section that serves it. On a 20V section the displacement code also sets the pressure ceiling, so a large cover-end code can hold the whole second circuit down. The original literature gives the same picture: a 3525V38A17 running 172 bar at the front section and 138 bar at the rear section is quoted as needing over 450 Nm of input torque, so the two sections are valued separately. Transient pressure may exceed the continuous rating by approximately 10% for no longer than 0.5 seconds, and selection is made on the continuous figure. The fluid sets a further limit: water-in-oil emulsion reduces the maximum continuous outlet pressure to 69 bar, water glycol allows 159 bar, and phosphate ester requires the F3 seal prefix in position 1.
Port, shaft, mounting and the two letters
Position 5 is A — the SAE 4-bolt flange — throughout the double line; the port carries two outlets in addition to the inlet, which is why doubles do not offer the straight-thread and split port options of the single pumps. Inlet and outlet flange sizes follow the frame: ø38.1/ø25.4 mm on 25V sections, ø50.8/ø31.8 mm on 35V and ø76.2/ø38.1 mm on 45V, with ø38.1/ø19.0 mm on the 20V section. Position 6 sets only the thread system of the flange fasteners — inch by default, M for metric.
| Pilot | Size | Shaft codes |
|---|---|---|
| Standard (position 3 omitted) | 20V section | 1 keyed · 151 splined |
| Standard (position 3 omitted) | 25V · 35V · 45V sections | 1 keyed · 86 heavy-duty keyed · 11 splined |
| S — SAE pilot | 25V · 35V · 45V sections | 202 · 203 · 297 |
| M — metric pilot | 25V · 35V · 45V sections | 292N |
The shaft code belongs to the pilot branch, so position 3 is read first. One shaft serves both sections, and its code describes the drive end that couples to the prime mover.
Position 10 carries two letters, one for each outlet, and both are read from the cover end. The first letter gives the position of outlet 1 and the second the position of outlet 2 relative to it:
| First letter (outlet 1) | Second letter (outlet 2) |
|---|---|
| A opposite the inlet | A 135° counter-clockwise |
| B 90° counter-clockwise | B 45° counter-clockwise |
| C inline with the inlet | C 45° clockwise |
| D 90° clockwise | D 135° clockwise |
So DD is outlet 1 ninety degrees clockwise with outlet 2 a further hundred and thirty-five degrees clockwise, and AA is outlet 1 opposite the inlet with outlet 2 at hundred and thirty-five counter-clockwise. 2525V and 4535V use a different map, because in those two frames the outlets are arranged differently: there the second letter is read as opposite the inlet, 90° counter-clockwise, inline, or 90° clockwise. Because the two sections share one port block, the pair of letters is what decides whether the second circuit can be piped at all in a given machine.
Standard mounting is the flange, F in position 8 specifying a foot bracket. Position 13 is a special suffix and is normally omitted.
Rotation and the design number
Rotation is judged at the shaft end: R is clockwise, L counter-clockwise, and an omitted position means right-hand. The design number identifies the generation of the frame — 22 on the V series.
Four stock codes, decoded
| Code | How it reads |
|---|---|
| 2520V10A2 1AA22R | 2520V, 25V shaft end with 20V cover end · shaft-end displacement 10 = 33 cm³/r · port A · cover-end displacement 2 = 7 cm³/r · shaft 1 keyed · outlets A and A · design 22, right-hand |
| 3520V25A11 1AA22R | 3520V, 35V shaft end with 20V cover end · 25 = 81 cm³/r · port A · 11 = 36 cm³/r · shaft 1 keyed · outlets A and A · design 22, right-hand |
| 4525V42A12 1AA22R | 4525V, 45V shaft end with 25V cover end · 42 = 138 cm³/r rated 172 bar · port A · 12 = 40 cm³/r · shaft 1 keyed · outlets A and A · design 22, right-hand |
| 4535V42A25 11AA22R | 4535V, 45V shaft end with 35V cover end · 42 = 138 cm³/r · port A · 25 = 81 cm³/r · shaft 11 splined · outlets A and A · design 22, right-hand |
Common ordering errors
- Applying one displacement to both sections. Positions 4 and 7 are read on different sizes, and the same code means different displacements on each.
- Taking the pressure limit from the frame. On a 20V section the displacement code sets the ceiling — a large cover-end code caps the second circuit.
- Ignoring the pair of outlet letters. Two outlets are positioned independently, and the wrong pair will not pipe up in the machine.
- Treating a different build as a double. A unit with a third section, or with a rear drive shaft for a second pump, shares the frame number but not the hardware: the rear cover, shaft length and port block differ, and the code carries extra positions. Confirm the build from the nameplate first.
Ordering
Send the complete model code from the nameplate, or the combination you need — frame, both displacement codes, shaft and outlet position — and we confirm both sections, the shaft and the port configuration before the order is placed. Where the nameplate is unreadable, photographs of the pump and of the port end, together with the machine model, are usually sufficient. Port flange kits and cartridge kits are ordered separately.
Browse the V double vane pumps or the V single vane pumps.
