SK Water Ring Vacuum Pumps & Compressors

Dimensions and flange positions are verified against the original pump before a quotation is issued.
SK water ring vacuum pumps and compressors, small compact single-stage units.
SK series: what the numbers mean and how to pick a frame
What does the number in an SK model name mean?
The number is the maximum suction capacity in m³/min: an SK-3 moves 3 m³/min (180 m³/h) and an SK-120 moves 120 m³/min (7,200 m³/h). Our SK catalogue also gives the capacity at −0.041 MPa gauge (about 600 mbar abs), which is 90–94% of the maximum — 5.4 m³/min for an SK-6, for example.
How deep a vacuum does an SK pump reach?
SK-3 through SK-120 reach about 80 mbar abs, which our catalogue states as −700 mmHg gauge; the small SK-0.4 and SK-0.8 reach about 120 mbar abs (−670 mmHg) and the SK-1.5 about 107 mbar abs (−680 mmHg). If your process needs 33 mbar abs, the 2BV and 2BE1 series on this site list frames rated to that figure; the SK suits duties that stay above 80 mbar.
Can an SK pump run as a compressor?
SK-0.4 to SK-30 can: our catalogue lists them as compressors for discharge pressures of 0 to 0.1 MPa gauge, and from SK-3 upward the compressor duty takes a larger motor — SK-3 uses 5.5 kW as a vacuum pump against 7.5 kW as a compressor, SK-12 18.5 kW against 30 kW, SK-30 55 kW against 75 kW. SK-42, SK-60, SK-85 and SK-120 are listed for vacuum duty only. State the duty with your enquiry, because the motor and starter differ.
What should I check before replacing an existing SK pump?
Check speed and port size first, because both change across the SK range: SK-0.4 and SK-0.8 run at 2,850 rpm with G1" ports, SK-6 and SK-12 have 80 mm ports at 1,440 and 970 rpm, and SK-120 runs at 490 rpm with 300 mm ports and weighs 5,520 kg. The SK is a flat-port machine with a port plate, not a cone; in our parts catalogue the port plate's typical interval is 2–4 years and gland packing 6–12 months. Send the model and serial or a nameplate photo, and we check flanges, bolt pattern and shaft height against the original drawing — if it doesn't match, we don't quote.
Model specifications
17 unique models · 25 configurations. Open a model to compare its available configurations.
SK-0.4Capacity24 m³/hUlt. pressure120 mbarMotor range1.5 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-0.4 | 24 | 120 | 1.5 | 2,850 | inlet/outlet G1" | 50 |
| SK-0.4 | 24 | — | 1.5 | 2,850 | inlet/outlet G1" | 50 |
SK-0.8Capacity48 m³/hUlt. pressure120 mbarMotor range2.2 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-0.8 | 48 | 120 | 2.2 | 2,850 | inlet/outlet G1" | 80 |
| SK-0.8 | 48 | — | 2.2 | 2,850 | inlet/outlet G1" | 80 |
SK-1.5Capacity90 m³/hUlt. pressure106.7 mbarMotor range4 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-1.5 | 90 | 106.7 | 4 | 1,440 | inlet/outlet 70 mm | 200 |
| SK-1.5 | 90 | — | 4 | 1,440 | inlet/outlet 70 mm | 200 |
SK-3Capacity180 m³/hUlt. pressure80 mbarMotor range5.5–7.5 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-3 | 180 | 80 | 5.5 | 1,440 | inlet/outlet 70 mm | 320 |
| SK-3 | 180 | — | 7.5 | 1,440 | inlet/outlet 70 mm | 320 |
SK-6Capacity360 m³/hUlt. pressure80 mbarMotor range11–15 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-6 | 360 | 80 | 11 | 1,440 | inlet/outlet 80 mm | 460 |
| SK-6 | 360 | — | 15 | 1,440 | inlet/outlet 80 mm | 460 |
SK-12Capacity720 m³/hUlt. pressure80 mbarMotor range18.5–30 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-12 | 720 | 80 | 18.5 | 970 | inlet/outlet 80 mm | 750 |
| SK-12 | 720 | — | 30 | 970 | inlet/outlet 80 mm | 750 |
SK-20Capacity1,200 m³/hUlt. pressure80 mbarMotor range37–55 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-20 | 1,200 | 80 | 37 | 730 | inlet/outlet 150 mm | 1,700 |
| SK-20 | 1,200 | — | 55 | 730 | inlet/outlet 150 mm | 1,700 |
SK-30Capacity1,800 m³/hUlt. pressure80 mbarMotor range55–75 kWConfigurations2Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-30 | 1,800 | 80 | 55 | 730 | inlet/outlet 150 mm | 2,300 |
| SK-30 | 1,800 | — | 75 | 730 | inlet/outlet 150 mm | 2,300 |
SK-42Capacity2,520 m³/hUlt. pressure80 mbarMotor range75 kWConfigurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-42 | 2,520 | 80 | 75 | 730 | inlet/outlet 150 mm | 2,500 |
SK-60Capacity3,600 m³/hUlt. pressure80 mbarMotor range95 kWConfigurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-60 | 3,600 | 80 | 95 | 550 | inlet/outlet 250 mm | 3,500 |
SK-85Capacity5,100 m³/hUlt. pressure80 mbarMotor range132 kWConfigurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-85 | 5,100 | 80 | 132 | 550 | inlet/outlet 250 mm | 3,800 |
SK-120Capacity7,200 m³/hUlt. pressure80 mbarMotor range185 kWConfigurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK-120 | 7,200 | 80 | 185 | 490 | inlet/outlet 300 mm | 5,520 |
SK0Capacity—Ult. pressure—Motor range—Configurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK0 | — | — | — | — | — | — |
SK1Capacity—Ult. pressure—Motor range—Configurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK1 | — | — | — | — | — | — |
SK07Capacity—Ult. pressure—Motor range—Configurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK07 | — | — | — | — | — | — |
SK25Capacity—Ult. pressure80 mbarMotor range37 kWConfigurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK25 | — | 80 | 37 | — | 100 mm | — |
SK070809Capacity—Ult. pressure—Motor range—Configurations1Quote this model →
| Model | Capacity (m³/h) | Ult. pressure (mbar) | Motor (kW) | Speed (rpm) | Port | Weight (kg) |
|---|---|---|---|---|---|---|
| SK070809 | — | — | — | — | — | — |
How we verify a bolt-on replacement
The quotation follows a drawing-led check before you place an order.
Send the original model
Share the nameplate model and your required duty.
We check the interface
We verify flange size and orientation, foundation bolt pattern and shaft height, then send the equivalent model and outline drawing.
You confirm before quotation
You review the drawing; after confirmation, we prepare the quotation.
What you get with the quotation
Tell us the duty point (capacity, suction pressure, seal-liquid temperature) and we return, normally within one working day:
- Performance curve — capacity against suction pressure at your seal-liquid temperature — not a catalogue figure
- Dimensional outline drawing — flanges, bolt pattern, shaft height, so you can check the fit before ordering
- Material specification — wetted-part materials for your gas and liquid, with certificates on delivery
- Utility figures — seal-liquid flow and motor rating, for sizing the supply and the starter
If the drawing does not match your original, we say so and do not quote.
Confirm the drawing before you order
Send the original model and duty. We will return the equivalent selection, outline drawing and performance curve with the quotation.