HYDRAULIC GROUP 1, 2 or 3 Gear Pumps in Double or Triple Configurations (2 and 3 pumps in a row) for machinery and earth moving equipment with drive motors for wheels, tracks and attachments as well as functions that use lift, tilt and or grab using cylinders.
Most hydraulic machines that have multiple functions that need to operate together at the same time will have more than one hydraulic pump bolted to the motor's bell housing.
For example, Earth Moving machines such as dozers and loaders need to move wheels or tracks and at the same time operate cylinders to lift blades, tilt buckets and operate attachments such as grinders and trenchers.
Sample video of tandem (double) gear pump with worn housing.
2 or 3 pumps in a row are used because if only one large pump is used, oil flow will always take the path of least resistance back to the tank, using only one pump to one valve, will not give wheeled/track-driven machines good performance.
Therefore the best way to get different functions to work at correct pressures simultaneously is to use two pumps & two-valves or 3 pumps and 3 valves.
An alternative to Gear pumps are balanced Vane pumps, Balanced Vane pumps have a few advantages over gear pumps, generally have a longer life, smoother operation, quieter, and much more cost-effective to modify and or rebuild.
If you are not sure how many gear or vane pumps and valves you require and what horsepower you will need as well as what oil flows each pump needs to supply?
Please contact our friendly team at hydraulic.online and our design guys will be only too willing to help you better understand your requirements as well as bring your project ideas and plans into reality.