Pedrollo CK Self-Priming Liquid Ring Pump 0.25-0.37 kW

Pedrollo CK pump explained

The Pedrollo CK is a compact self-priming liquid ring electric pump for diesel, naphtha and clean water, rated up to 40 l/min (2.4 m³/h), up to 35 m of head and 9 m of suction lift. It has a cast iron body, a brass impeller with open radial vanes and a Viton mechanical seal. Seven Star LLC supplies the CK in Oman and the GCC as an independent supplier in Muscat.

The family has two entries: the CK 50 at 0.37 kW with a shutoff head of 35 m, and the CK 50-BP at 0.25 kW with a head of 20 m over the first part of the flow range, with a lower power and a lower head. A lower-case m (CKm) marks the single-phase version, and the plain CK is three-phase. The manufacturer’s own page notes that the diesel and naphtha duty limit is +55 °C.

CK technical specifications

The values above come from the manufacturer technical data for the series. Individual models inside the CK range differ in power, head and current, so always confirm the exact model code before ordering.

How the CK works and what limits it

The mechanism is a liquid ring: a ring of liquid in the casing seals the impeller vanes, so the pump can pull a mixture of air and liquid and prime itself, making it suitable for irregular flow. The mechanical seal is ceramic, graphite and Viton (AR-12V), and the motor bracket has a front anti-locking shim function. Water temperatures can reach +90 °C, the pressure limit is 6 bar and IP X4 applies.

A self-priming jet pump combines a centrifugal impeller with an ejector fitted in the pump body. Part of the delivery flow is recirculated through the ejector nozzle, which creates the depression that draws air and water up the suction line, so the pump can evacuate the suction pipe and prime itself after the body has been filled once. Because the pump tolerates air mixed into the suction flow, it suits wells, tanks and cisterns where the water level changes. The suction lift is limited to the manometric value on the data sheet, and the check valve at the end of the suction line keeps the pipe full between starts.

CK models and performance data

The heads in this table are read from the first point of the manufacturer 50 Hz performance table and fall as flow increases, so use the full curve for the real duty point. Where a 60 Hz version is needed, ask us: the manufacturer states that 60 Hz motors are available on request for many models.

Where the CK fits: related Pedrollo pumps

For a higher flow and a bronze impeller see the CKR range, and for clean water jetting see the JSW and JCR. The PV range covers higher temperature water.

Selecting a CK pump: checklist

• Confirm the liquid: diesel, naphtha or clean non-corrosive water
• Choose CK 50 (35 m) or CK 50-BP (20 m head at low flow)
• Check the temperature: up to 90 °C water, up to 55 °C for diesel or naphtha
• Single-phase CKm or three-phase CK
• Review fire and explosion rules for the installation of any fuel-transfer pump

Installing and maintaining the CK

Install the pump close to the water source on a rigid base with the motor shaft horizontal. Use a suction pipe of at least the pump port size, laid with a constant upward slope and with all joints sealed, because any air leak lengthens priming time or stops it altogether. Fit a foot valve or check valve at the lower end of the suction pipe and a strainer to keep debris out of the ejector. Fill the pump body through the filling plug before the first start. On three-phase versions confirm the rotation direction. When the pump feeds a pressure tank, set the pressure switch and tank pre-charge to suit the duty so the unit does not cycle too often, and drain the pump in cold weather or when it will stand unused.

CK applications in Oman and the GCC

In the GCC the CK is a small fuel transfer pump for generator day tanks, workshop diesel dispensing and agricultural equipment. Do not treat it as a certified explosion-proof pump: the manufacturer’s data lists no such rating, and a fuel installation must follow local safety and fire regulations. Keep the suction line short and sealed.

Many Omani villas and farms use a ground tank with a transfer pump, and a self-priming pump is practical because the suction line can drain and refill with air. The main risks are warm water above the stated limit, sand from wells, and suction leaks. Shade the pump, fit a strainer, and check the foot valve for scale every year.

Information to send with your CK RFQ

• Flow and delivery pressure required at the point of use
• Water source (well, tank, cistern), suction lift and suction pipe length and diameter
• Liquid temperature and quality, including any sand in the source
• Supply: single-phase or three-phase, voltage, frequency
• Pressure tank, switch or control accessories needed, and the quantity required

Documents and quotation

The manufacturer datasheet for the CK is attached on this page, and the performance tables in it should be checked against your duty point. Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer.

Send the model code, quantity, voltage and frequency and the duty point, and we will confirm availability and prepare a quotation for Oman and the GCC.