How to Operate a locking pneumatic mast in safely manner?

You know the locking pneumatic telescopic mast have a long time working advantage than a non-locking mast.

when a locking mast extended fully then all locking pins are locked firmly in very section collar. And the locking mast can work very long time daily, weekly, monthly, even yearly without extra air supply in.

But how to retracted the locking mast safely after mast finished the longtime working?

You know, when a locking mast extended fully for working, people will not supply extra air pressure into the mast. After long time working, the air pressure in the mast very low can't support the top sections and payloads. If a person retract the mast, the top sections with payloads will be collapse suddenly, it is very danger for people and equipment. 

So pump air into the mast before retracting operation is needed.

1> firstly, pump air into the mast make sure the inner air pressure up to a certain level 0.2Mpa/29PSI the operation pressure

2> second,turn off the air compressor and stop air supply. 

3> pull down the first locking T handle, and operate the air control level to air release, waiting for top sections retract, then release the locking T handle, waiting for the second tube retract fully and operate the air control level to the middle position to keep air stay.

4> Pull down the second locking T handle, and operate the air control level to air release position, waiting fro top sections retract, then release the locking T handle, waiting for third tube retract fully and operate the air control level to the middle position to keep air stay.

........

repeat above operation to the mast retracted fully.