The value of the humble hydraulic symbol

I am regularly involved in troubleshooting problems with hydraulic equipment. In these situations, there are two things I always do before reaching for my test gear. The first is to conduct a visual inspection of the hydraulic system, checking all the obvious things that could cause the problem in question (never overlook the obvious). The second is to ask for the schematic diagram for the hydraulic circuit.

What is a hydraulic schematic diagram?

A hydraulic schematic diagram is a line drawing composed of hydraulic symbols that indicate the types of components the hydraulic circuit contains and how they are interconnected.

What makes a hydraulic schematic diagram valuable?

A schematic diagram is a 'road map' of the hydraulic system and to a technician skilled in reading and interpreting hydraulic symbols, is a valuable aid in identifying possible causes of a problem. This can save a lot of time and money when troubleshooting hydraulic problems.

If a schematic diagram is not available, the technician must trace the hydraulic circuit and identify its components in order to isolate possible causes of the problem. This can be a time-consuming process, depending on the complexity of the system. Worse still, if the circuit contains a valve manifold, the manifold may have to be removed and dismantled - just to establish what it's supposed to do. Reason being, if the function of a component within a hydraulic system is not known, it can be difficult to discount it as a possible cause of the problem. The humble hydraulic symbol eliminates the need to 'reverse engineer' the hydraulic circuit.

Where are all the hydraulic schematic diagrams?

As most hydraulic technicians know, there's usually a better than even chance that a schematic diagram will not be available for the hydraulic machine they've been called in to troubleshoot. This is unlikely to bother the technician because it is the machine owner who pays for its absence.

Where do all the hydraulic schematic diagrams go? They get lost or misplaced, they don't get transferred to the new owner when a machine is bought secondhand and in some cases they may not be issued to the machine owner at all. Why? Because generally speaking, hydraulic equipment owners don't place a lot of value on them.

So if you're responsible for hydraulic equipment and you don't have schematic diagrams for your existing machines, try to obtain them - before you need them. And ensure that you are issued with schematic diagrams for any additional hydraulic machines you acquire. It will save you time and money in the long run.

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