New era of finely controllable hydraulic pressing

MainTrains, which services trains for RailCorp and FreightCorp on behalf of the United Group, has adopted the Enerpac XVARI® XA air-over-hydraulic foot-operated pump for refurbishing the air brake assemblies of wheel bogies for a wide range of train types.
The technology - which is equally applicable to road vehicles, mining and construction plant and mobile machinery - has made train bogey overhauls easier because of the greater control it offers over the hydraulic pressing of air brakes during overhaul.
The high-speed Enerpac XVARI XA powers an Enerpac hydraulic ram that disassembles the air brake by compressing the spring that holds the brake on. The XVARI replaced a pump that was proving too unresponsive in use, with not enough foot control.
“When disassembling the air brake, you need to compress the spring slowly and in a controlled fashion, then reverse the procedure during reassembly. The XVARI XA pump, which has finely variable speed, gives this degree of control,” said Allan Burgess, sales manager of Stenline Fluid Power, the company which supplied the pump to MainTrains.
“The XVARI replaced an air-over-hydraulic pump which couldn’t be this finely controlled. The new pump works well for them - and is faster too.”
The 700 bar XVARI XA pump was launched throughout the world after extensive in-service testing to enable finer and safer control of tasks while completing jobs up to twice as quickly as conventional air-over-hydraulic pumps.
Efficiency and safety are built into the XVARI XA, which has high oil flow, with its rotating air motor and rotating two-stage pump element giving hydraulic delivery up to 50 per cent higher than conventional pumps with linear motor and single piston.
The technology is coupled with ergonomic two-pedal controlled advance and retract functions for time-efficient and safer hands-free operation with less operator fatigue and increased stability.
“Never before have these three vital advantages - tremendously high oil flow, precise control and ergonomic operation - been combined in one hydraulic pump,” said Enerpac customer support and engineering manager Tony Cooper.
“XVARI technology takes a revolutionary step into the future, setting a new industrial standard that eclipses the 50-year-old technology of conventional air-over-hydraulic foot pumps.”
XVARI technology allows users to continuously and precisely control the amount of hydraulic oil flow in the pump’s advance and retract mode, giving fine control of the speed of operation of the single-acting hydraulic cylinder or tool that the pump is powering.
This fine process control is especially valuable for jobs that require accurate load positioning, aligning and controlled descent. The better control improves productivity, enhances process quality and makes the workplace safer, said Cooper.
Enerpac market research showed many users wanted higher hydraulic delivery. The higher oil flow considerably reduces the time required to extend the cylinder or tool and build up maximum pressure.
(Outflow flow rates are 0.25 l/min at rated pressure, 2.0 l/min with no load, with a usable oil capacity of 1 litre and dynamic air pressure range of 2.1-8.6 bar).
For more information email: info@enerpac.com.au or visit: www.enerpac.com.au