FreeRange
Mechanical
- Mar 19, 2020
- 1
The tractor trailer hydraulic systems I work with need to be robust more so than efficient. A customers tractor has about 300 hp available for the PTO pump and may have anywhere from 8 to 50 GPM available flow. This creates an enormous challenge by itself but the biggest challenge is trying to convince an entire industry that hydraulic oil filters are necessary on modern hydraulic systems. Our standard system uses Wolverine Mono Block valves without a filter that have historically survived high levels of oil contamination and rigorous use. Filtration only became an issue when we decided to offer electronic controls as an option. These systems contained cartridge style directional control valves with various pressure and flow compensation. We ended up with numerous problems ranging from stuck spools to phantom movement of components and ultimately complete loss of system operation and the only thing we could do was change the cartridge valves and try to convince the customer to change their oil filter. I have found that the construction of the spool valve in our manually operated systems have metal on metal hardened seats where as the cartridge style valve use a viton rubber on metal seat. Being that I have no control over what a customer does to their hydraulic oil, my though is, that I could get a longer life span out of a valve with metal on metal seat which leaves me to piece the system together myself. My question to all the hydraulics engineers out there is; Why is there not a standard off the shelf electronically controlled hydraulic system available that is suitable for this huge industry?
