BUSCH COBRA AC 1000 F, Installation And Maintenance Instructions Manual

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Product Description
The COBRA AC 1000 F vacuum pump is conform to the European
Directive 2014/34/EU.
The vacuum pump is provided with the following protection marking
against explosions
II
inside (i) 2G IIB T4 X
outside (o) 2G IIB T4 X
Use
For a correct understanding, the term "injection liquid" corresponds to
the injection point t.
The term "cooling liquid" on the other hand corresponds to the
injection point p.
The COBRA AC 1000 F VR ATEX vacuum pump can draw explosive
gas mixtures and vapours of Zone 1 and can be installed inside a
zone 1. This pump has been developed to draw hydrocarbon gases and
vapours mainly.
It is possible to draw explosive gases or vapours of explosion group IIB
belonging to temperature class T4 with this vacuum pump. However,
to limit the temperature of the pump, it is necessary to inject cooling
liquid into the cylinder. This injection liquid can be a hydrocarbon.
WARNING
When using toxic, inflammable and/ or explosive gases, make sure
that the system corresponds in design to applicable local and na-
tional safety regulations and that all applicable safety measures are
followed.
All product-specific safety regulations must be observed.
Solid particles must not get into the vacuum pump.
The maximum admissible temperature of drawn gas is (or must be) of
70°C.
Max. permissible number of startings per hour: 6.
The vacuum pump is thermally suitable for continuous operation at any
pressure between atmospheric pressure and ultimate pressure.
Principle of operation
The COBRA vacuum pumps are screw vacuum pumps with cooling
liquid circuit. The screw rotors cooling must be made with cooling
liquid injection in the cylinder.
The COBRA vacuum pumps the principle of screw pumps. Two parallel
screws (RT) rotate in opposite directions in the pump body. Entering
gases are trapped between the pitches of the screws and the pump
body. The gases are conveyed by the rotation of the screws to the
exhaust side where they are discharged.
The COBRA vacuum pump is driven by an air-cooled motor.
Cooling
The vacuum pump is cooled by
–
through a cooling liquid (for example: water, hydrocarbons) in the
water chambers (CL) of the cylinder and the cylinder cover at the
inlet and at the motor side.
The cooling liquid circuit allows to stabilize the operating tempera-
ture of the vacuum pump
The cooling liquid flow must be such so as to guarantee a maxi-
mum temperature of 55°C at the sensor TSA+/0101 and must be
set at 12 l/min.
–
The screws (RT) are cooled by injecting cooling liquid into the
cylinder. The cylinder injection liquid flow must be set between
2 l/min and 6 l/min after starting the vacuum pump.
NOTE
:
The COBRA vacuum pumps are always shipped without oil and
cooling liquid. Operation without any of these lubricants will destroy
the vacuum pump within a short period of time.
Process diagram
Sealing systems
The COBRA vacuum pumps are equipped with oil lubricated single
mechanical seal with labyrinth seal on the motor side (A-side) and oil
lubricated single mechanical seal with lip seal on the inlet side (B-side)
as standard.
Motor side (A) Inlet side (B)
Oil lubricated single mechanical
seal with labyrinth seal Oil lubricated single mechanical
seal with lip seal
On/ Off switch
The vacuum pump is delivered without on/ off switch. The control of
the vacuum pump must be provided in the course of the installation.
Product Description
Page 4
FSA-
0502
TSA+
0102
PSA+
0301
SSA+
0701
FSA-
0501
LSA-
0201
TSA+
0101
LSA+
0202