Hydraulic Drive & Controls

Lesson No 31 Fail safe and safety systems in hydraulic and pneumatics

Fail safe devices

Fail safe devices are those  which even get failed but  responds in such a manner that it  will cause no harm or least harm  to other devices or  the system / sub system etc. These may be actuator, valves, etc.

Safety in Hydraulics

Consider the following points while observing the safety of a hydraulic circuit-

• Do not crack a  hydraulic connector for finding the  pressure, flow, etc. in a  hydraulic system.

• Do not leave or test  a hydraulic system or component to atmosphere, partially or fully  open a transmission line to atmosphere.

• Do not have the air bleeding in a hydraulic component or system to atmosphere

• Provide safe-T bleed in the hydraulic systems which is a safety device.

• Skilled and trained workers are to be put  on and around hydraulic systems from safety point of view.

• Park the hydraulic machines beyond the reach of children.

• Lower the machines to the ground before leaving the machines.

• Do not service the hydraulic system when motor or engine is running.

• Do not remove the cylinder until the working units are resting on the ground.

• Relieve the hydraulic pressure and discharge the accumulator before disconnecting oil lines

• Ensure there is no leakage and all the lines connections are tight.

• Make use of hoist or jacks to remove the heavy components of hydraulic system.

Safety in Pneumatics

Consider the following points while observing the safety of a pneumatic circuit-

• Operate the  pneumatic system within operating range of pressure

• While under pressure do not disconnect the lines.

• Do not activate the compressed air until all the line connections are complete.

• Take precautions while switching on the compressed air

• Make use of shortest lines possible.

• Make use of safety glasses

• Switch off the compressed air before repairing or dismantling the circuit.