Concentric pumps for JCB's 6-cylinder engine

Concentric AB is supplying oil and coolant pumps for JCB’s new 7.2 litre Dieselmax 672, the largest engine in the company's range which will be used in high-horsepower JCB excavators.

In accordance with JCB's intention to achieve a high degree of commonality with components used in the 4-cylinder engine, the new Concentric pumps are compact, robust designs similar to those already proven in several years of service on the Dieselmax 444. In order to accelerate the design and validation work, it was decided to test the initial prototypes on a rapid prototype representation of the engine block until cast blocks became available.

In excavators the new engine will spend significant time around its rated speed of 2000erpm, placing high loads on the cooling system, so Concentric's design validation program focussed specifically on eliminating cavitation issues in these applications. The coolant pump features a new conical impeller designed to fit into the same diameter housing as in the 4-cylinder version. Compared with the previous design, the oil pumps for the Dieselmax 672 increased in length to meet the increased flow requirement. They are manufactured in die-cast aluminium and feature an integral re-circulating valve to regulate pump pressure.

David Woolley, President and CEO of Concentric AB commented: “We have a long-standing relationship with JCB and have worked closely with them since they took the historic step of building their own engines and, indeed, setting a world speed record with the first 4-cylinder model. We are extremely pleased that Concentric has again been able to contribute its technology to what we hope will be another British world-beater.”

Dieselmax 672 will be available in ratings from 140kW (188hp) to 225kW (302hp) with a maximum torque output of 1200Nm (885 lb.ft.) and will initially be produced in an EU Stage 2 emissions standard for growth markets. The new engine is based on JCB's 4-cylinder Dieselmax and is the result of a two-year £45 million development programme. The design incorporates common rail fuel injection with electronic control and fixed geometry turbocharging, giving an 8% increase in fuel efficiency over previous engines in the JS excavator line.

For further information, please contact David Bessant, CFO, +44 121 445 6545

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