Basic Terms; Operating Media; Refrigerant; Refrigeration Machine Oils - GEA Grasso M-Series Operating Manual

Description of Design and Function
7.12.2

Basic terms

Refrigerant

Materials circulating in a plant (liq-
uid or gas), which by means of
their change of state of the pack-
age withdraw heat from another
medium (cooling or heating agent)
or can dissipate heat to this
medium.
Secondary Fluids that can absorb the heat of
refrigerant a system and dissipate it to a
refrigerant (reversible process)
and are used for the cooling of a
system (industrial process)
Heating Media (liquid or air), which trans-
agents port and emit the heat absorbed in
the secondary refrigerant. If water
is used as the heat carrier, the
terms warm water or cooling water
are also used.
7.12.3

Operating media

7.12.3.1 Refrigerant
The technical order specification defines the refriger-
ant used. All components of the screw compressor
package are designed for use with the defined refrig-
erant.
Hint!
The safety data sheet for the refriger-
ant used must be observed. The safety
data sheet is part of the product docu-
mentation.
48
7.12.3.2

Refrigeration machine oils

Caution!
In order to ensure an adequate load-
bearing capacity of the sleeve bear-
ings and to ensure the service life of
the roller bearings, a minimum viscos-
ity of 7cSt (=10
compressor is required. A suitable oil
must be carefully selected in consider-
ation of the operating conditions.
The selection criteria and selection
tables are summarised in the technical
information document entitled "Lubri-
cant oils for screw compressors". This
technical information forms part of the
product documentation.
GEA Refrigeration Germany GmbH can
provide assistance in the selection of
a suitable refrigeration machine oil on
request.
7.12.3.3

Secondary refrigerant

• Low corrosion water
• Permitted brine levels: see Grasso Design Pro-
gram
Hint!
For other secondary refrigerants, com-
patibility with the materials used must
be ensured.
7.12.4

Operating limits

The screw compressors can be operated under the
most varied operating conditions within the given lim-
its of application according to the requirements
involved. The limits of application listed below for the
screw compressors are based on the operational
principle of the screw compressor and thermody-
namic ratios and are based on practical operating
conditions and design. The tabulated data apply for
single, two-stage and heat pump operation. Depend-
ing on the compressor the manufacturer selected,
the specific operating conditions limitations may
occur within the parameters in the table.
GEA Refrigeration Germany GmbH | P_261511_1 | Generated 01.04.2015
Operating Manual | GEA Grasso M-Series
Screw Compressor Packages
-6
m²/s) upstream of the