ATEX UNLOADER AND RELIEF VALVES
SAFETY NOTE
SN03
Rev. 00
Date 27/10/2020
Pag. 9 of 10
It is always necessary to verify the non-existence of potential explosive atmospheres and the impossibility to trigger
off.
The user must certify that the operator is opportunely instructed to carry out all the safety procedures & hygiene in
the work areas according to the protocol in order to avoid any eventual risks deriving from the operations mentioned
above.
3.6.2 ORDINARY MAINTENANCE AND CLEANING
The cleaning stages are to be carried out regularly depending on the use and are obligatory in situations where foreign
bodies and/or exploding powders are present on the valve and on the drains ((independently from the settled
thickness).
Before carrying out periodic cleaning operations, it is absolutely essential to release the internal pressure on the
protected equipment by means of the relevant pipe into a safe zone to avoid uncontrolled atmospheres being
generated; verify that the unloading phase is complete by means of control devices. Then disconnect the service
connections using the methods required for the use of tools and completely empty the valve of all the product inside
it.
For internal and external cleaning, it is necessary to use non corrosive products or solutions, suitable to remove the
work residue, and that do not damage the O-ring surfaces. For the cleaning operations do not use aggressive chemical
detergents a/o mechanical systems that can cut or deform the valve.
The above operations must not jeopardize the alignment of the internal parts and the seal between seat and
valve shutter/sphere.
For the cleaning operations, do not use aggressive chemicals and/or mechanical systems that can
cut into or deform the valve.
Before reusing and/or reinstalling the VALVE, after washing or general maintenance or any other operation
deemed necessary, carry out the procedure provided in point 3.2.
3.6.3 EXTRAORDINARY MAINTENANCE AND REPAIR
Please check the internal parts every 300 / 400 hours of work in order to verify any premature wear of the parts.
Replacement of the dynamic seals is recommended:
VB23A-280: pos. 9-10 and 21
VB26A-280: pos. 6-7 and 19
VB33A-280: pos. 5-6 and 19-20
VB43A: pos. 6-7 and 18
VB80A: pos. various, identified with letter A
VS26A: pos.5 and 9-10
VS43A: pos. 7 and 16
VS80A: pos. various, identified with letter A
Verify that the slide surfaces of the seals are in good conditions: replace the parts if worn out or if damaged.
Use only original “PA” spare parts.
Lubricate only with silicone grease (14.6552.00) and do not use mineral grease or oil otherwise internal parts will be
subject to rupture.
