Marian Tumarkin, co-author of Hydraulics Made Easy and Advanced Hydraulic Control, sent me an interesting article published in the BBC's News Magazine, called: Diagrams that Changed the World.
One of the examples the article's author Marcus Sautoy cites, involves Florence Nightingale. As Sautoy explains:
"Although better known for her contributions to nursing, her greatest achievements were mathematical. She was the first to use the idea of a pie chart to represent data. She had discovered that the majority of deaths in the Crimean War were due to poor sanitation rather than casualties in battle. She wanted to persuade government of the need for better hygiene in hospitals but realised that just looking at the numbers was unlikely to impress ministers. But once those numbers were translated into a picture - her 'Diagram of the Causes of Mortality in the Army in the East' - the message could not be ignored."
A good diagram is indeed worth a thousand words (or numbers in Nightingale's case). It can also be worth a lot of nickel. Consider the four main types of hydraulic diagrams in common use -- and the consequences of having to manage without them:
Block Diagrams show the components of a circuit as blocks joined by lines, which indicate connections and/or interactions.
Cutaway Diagrams show the internal construction of the components and flow paths. Because these diagrams typically use colors, shades or patterns in the lines and passages, they are very effective at illustrating different flow and pressure conditions.
Pictorial Diagrams shows a circuit's components and piping arrangement. The components are seen externally and are usually in a close reproduction of their actual shapes in scaled sizes. This aids in component recognition and identification.
Graphical Diagrams are the shorthand system of the fluid power industry. They comprise simple, geometric symbols, drawn to ANSI or ISO standards that represent the components, their controls and connections.
To a technician skilled in reading and interpreting them, a graphical circuit diagram or schematic is a valuable aid in identifying possible causes of a problem. And this can save a lot of time and money in a troubleshooting situation.
If a schematic diagram is not available, the technician must manually trace the actual, physical 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. Because if the function of a component within a system is not known, it can be difficult to discount it as a possible cause of the problem. Schematic diagrams eliminate the need to reverse engineer the hydraulic system.
Where are YOUR hydraulic schematics?
As most hydraulic technicians know from experience, there's usually a better than even chance that a circuit diagram will not be available for the machine they've been called in to troubleshoot. But this is unlikely to bother the technician, because it is the machine owner who usually pays for its absence through prolonged service calls and increased downtime.
Where do all the hydraulic diagrams go? They get lost or misplaced, they don't get transferred to the new owner when a used machine is traded, 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 the upkeep of hydraulic equipment and you don't have schematic diagrams for your existing machines, try to obtain them - BEFORE you need them. And always ensure that you're issued with schematic diagrams for any additional hydraulic machines you acquire. It's a picture which can be worth a thousand dollars.
 | "This book has the potential to save many organizations lots of money. It should be on the bookshelf of every engineer, supervisor, planner and technician who deals with hydraulic equipment... it's worth its weight in gold." Find out more Alexander (Sandy) Dunn
Plant Maintenance Resource Center |
