AUMA Part-turn gearboxes GS 50.3 - 250.3, primary reduction gearings VZ 2.3 - 4.3_GZ 160.3 - 250.3 - Manual (Page 18)

11. Enclosure protection IP 68
Definition According to EN 60 529, the conditions for meeting the requirements of enclosure
protection IP 68 (requirements exceed those of IP 67) are to be agreed between
manufacturer and user. AUMA worm gearboxes and primary reduction gearings in
enclosure protection IP 68 meet the following requirements according to AUMA:
.
IP 68-3, submersible in water up to 3 m head of water
.
IP 68-6, submersible in water up to 6 m head of water
.
IP 68-10, submersible in water up to 10 m head of water
.
IP 68-20, submersible in water up to 20 m head of water
For size GS 50.3, only enclosure protection IP 68-3 is available.
If submersed in other media, additional measures for corrosion protection may be
necessary; please consult AUMA. Submersion in aggressive media, e.g. acids or
alkaline solutions, is not permitted.
Review Gearboxes in enclosure protection IP 68-3 were type tested in the factory.
Gearboxes in enclosure protection IP 68-6, IP 68-10 and IP 68-20 undergo a
routine testing for tightness in the factory.
Note:
.
The enclosure protection IP 68 refers to the interior of the gearboxes, but not to
the coupling compartment. .
If the gearboxes are likely to be repeatedly submersed, a higher corrosion
protection KS or KX is required. .
For gearboxes intended for buried service we strongly recommend to use the
higher corrosion protection KS or KX. .
For horizontal outdoor installation of the gearboxes, a sealed pointer cover
should be used.
For gas applications with sealed pointer cover, an air vent in the pointer cover or
venting grooves in the valve mounting flange must be provided.
.
In case of permanent submersion of the gearboxes or for buried service, a
protection cover must be fitted instead of a pointer cover. This will be taken into
account in the factory if indicated on the purchase order. Subsequent exchange
of the pointer cover for the protection cover is possible.
.
Use suitable sealing material between valve flange and gearbox.
.
Water can enter into the coupling compartment along the valve shaft. This would
lead to corrosion of hub and coupling. Therefore a suitable anticorrosive (or
sticky grease) must be applied to the hub and coupling of the gearbox before
mounting.
.
With corrosion protection KX, the hub and coupling are provided with a high
quality corrosion protection as standard.
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Worm gearboxes GS 50.3 – GS 250.3 Operation instructions