Higher power density for
hydrostatic propel drives – with p+

Pressure increase for series 02 enables greater output and downsizing of drives

More torque, higher travel speed or downsizing of the drive with identical power? Construction equipment manufacturers who use variable displacement pumps and motors series 02 from Linde will now be able to choose. And all this because pumps and motors - core components in many hydrostatic propel drives, like in wheel loaders, telescopic handlers, road rollers or graders - can now be operated with an effective pressure of 500 bar instead of the previously possible 420 bar, as long as defined field conditions are met. The user in this case not even has to accept any limitations concerning safety, availability and service life of the equipment.

The increase of the effective pressure range of Linde hydrostats from 420 to 500 bar provides the manufacturers of mobile machines with more flexibility in the design of their drives and extends the boundaries of the machine’s performance. Increased speed, enhanced tractive effort or smaller space requirements are the main advantages of p+.

The benefits this higher pressure range of the hydrostatic drive now offers for both the construction equipment manufacturer and the operator are quite obvious. The additional pressure can be utilized to achieve higher travel speeds. This only requires the use of a longer gear ratio in the working and road travel gear. Or one uses the 20% torque increase to provide the driver with a 20% higher tractive effort and thus higher power reserves. This increases the productivity of construction equipment.

A third possibility is the downsizing of the drive: If the OEM is satisfied with the available power of the machine, he may use smaller series 02 units and thus be able to reduce installation space as well as losses.

With this offer, that was introduced under the designation p+, Linde Hydraulics accounts for the request of mobile machines’ manufacturers to reduce the installation space for the drive, while increasing the efficiency at the same time. This option has already found a very positive response from the agricultural equipment industry during the "Agritechnica" exhibition.

As an example, the tractive effort of a wheel loader equipped with a combination of HPV 75-02 CA (pump) and HMV 135-02 (motor) can be increased from 50 kN to 60 kN - without any extra costs and additional weight. Another example: A telescopic handler with hydrostatic propel drive consisting of a pump HPV 55-02 and a motor HMV 165-02. In this case only the transmission ratio needs to be adapted to be able to increase the travel speed from 32 to 40 km/h.

Such improvements can always be achieved with high energy efficiency. Utilizing this higher pressure range increases the power density of hydrostatic equipment while nominal sizes remain unchanged. This is why the p+-concept is an excellent choice also under the aspects of fuel economy and environmental protection.

The benefits of p+ perfectly match the LinDrive concept, intended to provide manufacturers and users with hydrostatic drives, which are characterized by high dynamics and precision as well as high energy efficiency and reliability.