Pedrollo CKR Self-Priming Liquid Ring Pump Bronze Impeller

Pedrollo CKR pump explained

The Pedrollo CKR is a self-priming liquid ring pump with a bronze star-type open impeller, rated up to 70 l/min (4.2 m³/h), up to 60 m of head and 9 m of suction lift. The two models, CKR 90 and CKR 100, both use a 0.75 kW (1 HP) motor. Seven Star LLC supplies the CKR in Oman and the GCC as an independent supplier in Muscat, not affiliated with the manufacturer.

The CKR 90 is the high-head version, with 60 m at the first table point falling to 7 m at 70 l/min. The CKR 100 is the high-flow version with 40 m at the first point and 5 m at 70 l/min. The m prefix (CKRm) denotes single-phase, and the standard CKR is three-phase. Both models share the bronze star-type impeller and the stainless steel front shaving surface in the pump body.

CKR technical specifications

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

How the CKR works and what limits it

The front surface of the pump body is stainless steel, which helps prevent the impeller from locking because of oxidation after a long idle period. Other construction data: cast iron body, aluminium motor bracket with a brass cover, stainless steel AISI 431 shaft and a ceramic, graphite and Viton seal. Limits are 6 bar working pressure, liquid -10 to +90 °C, ambient up to +40 °C and IP X4.

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.

CKR 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 CKR fits: related Pedrollo pumps

For a smaller flow with a brass impeller see the CK. For clean cold water with a stainless body see the JCR. Higher-pressure options include the PV and PQ peripheral families.

Selecting a CKR pump: checklist

• Select the CKR 90 for head or the CKR 100 for flow
• Check the liquid is clean and non-corrosive
• Confirm temperature (up to 90 °C) and 6 bar limit
• Single-phase CKRm or three-phase CKR
• Check suction lift of 9 m or less

Installing and maintaining the CKR

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.

CKR applications in Oman and the GCC

The CKR is used for small hot-water or fuel-type transfer jobs where a self-priming, air-tolerant pump is practical, for instance workshop circulation, boiler feed top-up in small plants and transfer between tanks. Bronze impellers resist some corrosion that attacks other metals, but the manufacturer states that the pump is for non-corrosive liquids only.

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 CKR 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 CKR 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.