What do lifting chains, bladder-type accumulators and hydraulic hoses all have in common? Well, they typically have only one mode of failure – and that’s catastrophic. One minute they’re working as they should and the next thing you know, they’ve gone to hell.

Oh sure, hoses can leak from around their ferrules and show obvious signs of abrasion, both of which are early warning signs that a change-out would be prudent. But even under these conditions, estimating their remaining service life is virtually impossible.

The Trouble With Hose

Beyond the fact that their service life is finite and difficult to estimate, other disadvantages of hydraulic hoses when compared to tube include:

• They expand and stretch under pressure.

… continue reading »

According to an article by hose manufacturer Gates, it is estimated that 370 million liters of oil leak from hydraulic equipment each year. This is a staggering statistic. And even more so when you consider the same article states that as little as one liter of oil can pollute up to one million liters of water.

Here’s a ‘what if?’ scenario for you: what if the environmentalists smartened up and lobbied governments to pass a law requiring all hydraulic equipment users to account for and document all deliveries and disposals of hydraulic oil.

So you’d have an opening volume, then X gallons of new oil deliveries throughout the year and X gallons of used oil sent for disposal during the same period.… continue reading »

In the current trend of increasing energy costs, which appears to be underpinned by big-picture issues such as peak oil and carbon emission reduction, there is a growing awareness of the need to make hydraulic systems more efficient.

The three obvious ways of doing this are:

1. Use components with higher native efficiency: a piston pump instead of a gear pump, for example.
2. Minimize the use of energy-loss devices, such as flow controls, pressure reducing valves and even proportional valves.
3. Design the circuit so that energy is not consumed when work is not being done; unloading the pump between cycles or employing load-sensing control, for example.… continue reading »