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MATERIAL SELECTION AND CERTIFICATION under control: SIAD MI has developed dedica-
Continuing with the aim of minimizing ignition haz- ted solutions to constantly monitor the tempe-
ards using proper components: material parts in rature trends of the oxygen flow within the com-
contact with O (including for instance: gaskets, pressor package and thus prevent any potential
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sealing materials, piping, valves, instrumentation) issue.
have to be carefully selected and properly cleaned
/ degreased with dedicated cleaning agents for O
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use in order to avoid impingement at any operat-
ing condition. Furthermore, specific certifications The SIAD MI Oxygen
can be required, like certification by German BAM compressor: the best solution
(acronym of “Bundes Anstalt fur Materialforschung
und Prüfung”, so “Federal institute for material re- for the challenge
search and testing”) required for non-metallic ma- What are the main features embedded in a SIAD MI
terial certification. O compressor package? And how is it compliant
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to general safety rules?
ROBUST DESIGN We can split the compression package into its two
Design of the package is another significant fac- main components (bare compressor and compres-
tor: a very robust design of the components of the sor skid) and detail their main technical features, as
compressor skid is needed, to avoid mechanical far as O compression is concerned:
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breakages and/or uncontrolled contacts and con-
sequent spark ignition. For example: the protection THE BARE COMPRESSOR
system of V-belts, when used for power transmis- • Seal, guide rings and non-metallic compo-
sion, is made from non-sparking metal. In addition, nents in BAM certified material
the installation of specific O -suitable instrumenta- • Conservative sizing of piston rings and rider
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tion is essential, in order to prevent any unexpected rings
event. • Pistons made with anti-ignition materials

LOW VIBRATION THE COMPRESSOR SKID
Last but not least is one of the initial design phases, The design of the entire skid follows specific inter-
dedicated to careful compressor selection based nal standards aimed at guaranteeing reliability.
on ambient and process parameters: during this Here are some aspects:
analysis, SIAD MI is always looking to select with • Gas piping sized to minimize pressure drops
particular care the lowest possible compressor and the possibility of an area with sudden
frame speed in order to achieve as fully as pos- changes in diameter or other impact possibi-
sible a balanced arrangement of the reciprocating lities.
masses (i.e. piston masses) to minimize dynamic • Fitting and welding of piping pressure taps are
loads and vibration. executed according to piping class specific for
oxygen application
OIL-FREE TECHNOLOGY • Application of frequent piping supports to mi-
Oil-free technology is essential in an Oxygen com- nimize displacements
pressor and the extensive experience at SIAD MI • Choice of congruent component materials
has resulted in the production of oil-free oxygen
compressors, maintaining high performance, reli-
ability and availability.
SEPARATION
An oil-free compressor doesn’t mean that the
compressor can work without oil: there is oil in
the crankcase (mechanical part). Hence the need
to create an effective separation between the lu-
bricated parts of the crankcase and the totally oil-
free components (pneumatic parts) in contact with
Oxygen. To reach this objective, different solutions
are adopted, among which a single-compartment,
white painted, long distance piece (so: longer than
the stroke) called a “Type B” as per the API618
standard and vented on the outside with perforat-
ed and transparent covers and an emergency snap
opening. In addition, we have crankcases depres-
surized with a special blower plus various other
tailor-made solutions.

CONTROLLED TEMPERATURE
Temperature is a key factor to keep risk factors Picture 3: Oil free Design with Physical Atmospheric barrier

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