What a V single pump is
A V single pump is a balanced vane pump with one pumping cartridge on one shaft and a fixed displacement; two opposed pumping chambers balance the radial load, so it runs at higher pressure and lower noise than a single-chamber vane pump of the same size. The family has four sizes — 20V, 25V, 35V and 45V — covering 7 cm³/r to 193 cm³/r, rated 172 bar continuous on 25V, 35V and 45V and up to 207 bar on the 20V where the displacement code permits, at 600–1800 r/min (maximum falls to 1200 r/min on synthetic and water-in-oil emulsion fluids and 1500 r/min on water glycol). All units are cartridge type, so a worn pump is reconditioned by replacing the cartridge rather than the complete unit.
The 12 code positions
Every V single pump is ordered through the same 12 positions. A position is omitted when the standard value applies, and an omitted position does not shift those that follow it.
| # | Position | Values |
|---|---|---|
| 1 | Seals | F3 for phosphate-ester and fire-resistant fluids; omitted for mineral oil |
| 2 | Series (size) | 20V · 25V · 35V · 45V |
| 3 | Pilot | Omitted = standard; S = SAE; M = metric — S and M do not apply to 20V |
| 4 | Displacement | Code from the displacement table below |
| 5 | Port | A = SAE 4-bolt flange |
| 6 | Port thread | Omitted = inch; M = metric — not available on 20V |
| 7 | Mounting | Omitted = flange; F = foot |
| 8 | Shaft | Shaft table below |
| 9 | Outlet position | A · B · C · D |
| 10 | Design number | 22 |
| 11 | Rotation | L or R; omitted means right-hand |
| 12 | Special | 167 = 2-bolt 5.00 in pilot — 25V only |
The string is written in four groups rather than as a continuous sequence: series with pilot, displacement, port with thread system and mounting, then after the hyphen shaft, outlet position, design number and rotation — 25V10A 11A22R and 25V 10 A – 11 A 22 R denote the same pump. Note that position 6 is the thread system of the port fasteners and position 3 the mounting pilot, which are independent choices.
Position 4: displacement codes
| 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 = 39 14 = 45 17 = 55 21 = 67 |
25 = 81 30 = 97 35 = 112 38 = 121 |
42 = 138 45 = 147 50 = 162 60 = 193 |
The digits are not a size sequence; they express the nominal flow in US gpm at 1200 r/min. Code 14 is therefore 45 cm³/r on both 20V and 25V, while code 25 is 81 cm³/r on the 35V.
Pressure is taken from the code, not from the size
| Size | Maximum continuous pressure |
|---|---|
| 20V | 207 bar on codes 5, 8 and 11; 159 bar on code 12; 138 bar on codes 2 and 14 |
| 25V · 35V · 45V | 172 bar on every displacement code |
On 25V, 35V and 45V the displacement code changes displacement only and the pressure remains 172 bar; on the 20V it also sets the pressure limit, and only codes 5, 8 and 11 reach 207 bar. A 20V14 is limited to 138 bar and is not suitable for a 175 bar circuit. 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 also sets the limit: water-in-oil emulsion reduces maximum continuous outlet pressure to 69 bar, water glycol allows 159 bar (138 bar on the 20V codes 2 and 14), and phosphate ester requires the F3 seal prefix in position 1.
Position 8: shaft codes
| Pilot | Size | Shaft codes |
|---|---|---|
| Standard (position 3 omitted) | 20V | 1 keyed · 151 splined |
| Standard (position 3 omitted) | 25V · 35V · 45V | 1 keyed · 86 heavy-duty keyed · 11 splined |
| S — SAE pilot | 25V · 35V · 45V | 202 · 203 · 297 |
| M — metric pilot | 25V · 35V · 45V | 292N |
The shaft code belongs to the pilot branch, so position 3 is read first; the heavy-duty keyed shaft 86 is not available on the 20V.
Positions 5, 6, 7 and 12: ports and mounting
Position 5 is A — the SAE 4-bolt flange — throughout the line, and position 6 sets the thread system of the fasteners holding it: inch by default, or M for metric, available on 25V, 35V and 45V but not on the 20V. Inlet and outlet flange sizes are ø38.1/ø19.0 mm on the 20V, ø38.1/ø25.4 mm on the 25V, ø50.8/ø31.8 mm on the 35V and ø76.2/ø38.1 mm on the 45V, with metric thread alternatives. On the 20V the outlet bore may itself be tapped M10 even though the code provides no position 6 to record it, so the port should be confirmed on the pump.
Standard mounting is the flange, F in position 7 specifying a foot bracket; the mounting pilot and bolt centres are identified as 101-2 on the 20V and 25V and 127-2 on the 35V and 45V. Position 12 is uncommon — 167 denotes a 2-bolt 5.00 in pilot, listed on the 25V only.
Positions 9 and 11: outlet position and rotation
These two positions are read from opposite ends of the pump.
| Position | Read from | Values |
|---|---|---|
| 9 — outlet position | Cover end | A opposite the inlet · B 90° counter-clockwise from the inlet · C in line with the inlet · D 90° clockwise from the inlet |
| 11 — rotation | Shaft end | L left-hand (counter-clockwise) · R right-hand (clockwise); omitted means right-hand |
Position C is identified by the outlet lying on the same line as the inlet, whereas B and D are mirror images.
Four stock codes, decoded
| Code | How it reads |
|---|---|
| 20V5A 151A 22L | 20V · displacement 5 = 18 cm³/r, rated 207 bar · shaft 151 splined · outlet A, opposite the inlet · design 22 · left-hand |
| 25V10A 11A22R | 25V · displacement 10 = 33 cm³/r · shaft 11 splined · outlet A · design 22 · right-hand |
| 35V 38A 86C 22R | 35V · displacement 38 = 121 cm³/r · shaft 86 heavy-duty keyed · outlet C, in line with the inlet · design 22 · right-hand |
| 45V42A 11A 22R | 45V · displacement 42 = 138 cm³/r · shaft 11 splined · outlet A · design 22 · right-hand (standard pilot) |
Each code links to its product page. A practical check on a worn nameplate: the V series carries design number 22 and the VQ series 20, so a string ending in 20 is a VQ pump following a different 10-position code.
Common ordering errors
- “V20” and “20V” are different families. 20V, 25V, 35V and 45V are this balanced vane line; V10 and V20 are a smaller industrial family with their own code and parts.
- Taking pressure from the size rather than the code. Only three 20V displacement codes reach 207 bar.
- Reading rotation from the cover end. Rotation is judged at the shaft end, so the letter is reversed.
Ordering
All units are new aftermarket replacements, quality checked before shipping. Where a second pump is mounted on the rear, the unit is a through-drive type rather than a standard single pump and carries a different code. Send the complete model code from the nameplate, or the code required, and we confirm displacement, shaft and port configuration before the order is placed; where the nameplate is unreadable, photographs and the machine model are sufficient.
Browse the V single vane pumps, the V and VQ single pumps, the V · VQ · 50V series hub, or the V and VQ cartridge kits.
