Specific heat is a numeric value which refers to the amount of heat required to raise a set quantity of a substance by a fixed temperature. For example, pure water has a specific heat of 1. This means one calorie will raise the temperature of one gram of water by one degree C. Or, in U.S. units, one BTU will … Read more
What to Look For When Hydraulic Spool Valves Stick
Why do hydraulic spool valves sometimes stick? In a word: contamination. The radial clearance between the spool and bore in common, garden-variety directional control valves ranges between 3 and 13 microns. And in practice, perfectly round and straight bores are difficult to achieve. This is why servo and servo-proportional valves are fitted with a sleeve between the spool and bore-for … Read more
When NOT To Use Wire Reinforced Hydraulic Hose
A recent client engaged me to design the hydraulic steering system for a luxury motor yacht he was building. During installation, the installer questioned why I specified thermoplastic hose for the sections where stainless steel tube was not able to be used.
For those not familiar, thermoplastic hose (Synflex, Parflex, etc) is entirely reinforced with synthetic fibers. And this is … Read more