Through the gas bal last valve (470-480) a small amount of am bient air
is suc ked into the pump cham ber and com pres sed to ge ther with the
pro cess gas. This coun te racts the ac cu mu la tion of conden sa tes from
the pro cess gas in side the va cuum pump (see also “Ope ra tion Notes”).
Gas bal last ver sion with ball valve:
The gas bal last line can be clo sed par tial ly or com ple te ly by means of a
ball valve (477).
In or der to im prove the ope ra ting cha rac te ris tics the ou tlet of the pump
cham ber is equip ped with a spring loa ded valve (g,159).
Oil Circulation
The va cuum pump re qui res oil to seal the gaps, to lu bri cate the va -
nes(n,22) and to car ry away com pres sion heat.
The oil re ser voir is lo ca ted on the pres sure side of the va cuum pump
(i.e. high pres sure) at the bot tom of the bot tom cham ber of the oil se -
pa ra tor (f,75).
The feed ope nings are lo ca ted on the suc tion side of the va cuum pump
(i.e. low pres sure).
For ced by the pres sure dif fe rence bet ween pres sure side and suc tion
side oil is being drawn from the oil se pa ra tor (f,75) through the oil sup -
ply li nes and in jec ted on the suc tion side.
To ge ther with the suc ked gas the in jec ted oil gets conveyed through
the va cuum pump and ejec ted into the oil mist se pa ra tor (f,75). Oil
that se pa ra tes be fore the ex haust fil ter ac cu mu la tes at the bot tom of
the bot tom cham ber of the oil separator (f,75).
Oil that is se pa ra ted by the ex haust fil ter (l,120) ac cu mu la tes at the
bot tom of the up per cham ber of the oil se pa ra tor (f,75).
The flow re sis tance of the ex haust fil ters (l,120) cau ses the in side of
the ex haust fil ters (which is connec ted to be bot tom cham ber of the oil
se pa ra tor) to be on a hig her pres sure le vel than the out side of the ex -
haust fil ters (i.e. the up per cham ber of the oil se pa ra tor). Be cause of
the hig her pres sure in the bot tom cham ber it is not pos sible to let oil
that drips off the ex haust fil ters sim ply flow down to the bottom
chamber.
The re fore the oil that ac cu mu la tes in the up per cham ber is suc ked by
the le vel switch (m,194) through the oil re turn line (290) right to the
suc tion connec tion (250).
Cooling
The va cuum pump is co o led by
–
the am bient air around the va cuum pump, in clu ding oil mist se pa -
ra tor (f,75)
–
the air flow from the fan wheel (400)
–
the conveyed gas
–
the air flow from the fan wheels (321,322) on the shaft of the va -
cuum pump
Operational Options / Use of
Optionally Available Equipment
In or der to fa ci li tate the start of the pump, an of floa ding valve (op tio -
nal) with an ex haust line can be ins tal led.
To con trol the oil le vel in the oil mist se pa ra tor, an oil le vel switch is
moun ted in the oil mist se pa ra tor (as ope ra tio nal option).
In case of un fa vou rable tem pe ra ture condi tions, a heat ex chan ger (wa -
ter-oil) can be moun ted as a com ple men ta ry co o ling (optional).
To suck conden sable va pours, a gas bal last valve (op tio nal) can be ins -
tal led in the cy lin der co ver at fan side. To in crease the ca pa ci ty of va -
pours, ano ther gas bal last valve can be ins tal led in the cy lin der co ver at
the mo tor side. The valve can open or close the gas bal last du ring the
operation of the pump.
In or der to en sure the best ul ti mate pres sure du ring the pro cess, a so le -
noid valve (op tio nal) can be ins tal led be fore the gas bal last valve. The
so le noid valve can be used as a purge at the end of the process.
On/Off switch
The va cuum pump co mes wi thout on/off switch. The con trol of the
va cuum pump is to be pro vi ded in the course of ins tal la tion
Safety
Intended use
DEFINITION
: : For the pur pose of these ins truc tions, “han dling” the
va cuum pump means the trans port, sto rage, ins tal la tion, com mis sio -
ning, in fluence on ope ra ting condi tions, main te nance, trou bles ho o ting
and over haul of the vacuum pump.
The va cuum pump is in ten ded for in dus trial use. It shall be han dled
only by qua li fied per son nel.
The al lo wed me dia and ope ra tio nal li mits ac cor ding to the “Pro duct
Des crip tion” and the “Instal la tion Pre re qui si tes” of the va cuum pump
shall be ob ser ved both by the ma nu fac tu rer of the ma chi ne ry into
which the va cuum pump is to be in cor po ra ted and by the ope ra tor.
The main te nance ins truc tions shall be ob ser ved.
Prior to han dling the va cuum pump these ope ra ting ins truc tions shall
be read and un ders to od. If any thing re mains to be cla ri fied please
contact your Busch re pre sen ta tive!
Safety notes
The va cuum pump has been de si gned and ma nu fac tu red ac cor ding to
the state-of-the-art. Ne ver the less, re si dual risks may re main. These
ope ra ting ins truc tions in form about po ten tial ha zards where ap pro -
priate. Sa fe ty no tes are tag ged with one of the key words DANGER,
WARNING and CAUTION as follows:
DANGER
Dis re gard of this sa fe ty note will al ways lead to ac ci dents with fa -
tal or se rious in ju ries.
WARNING
Dis re gard of this sa fe ty note may lead to ac ci dents with fa tal or se -
rious in ju ries.
CAUTION
Dis re gard of this sa fe ty note may lead to ac ci dents with mi nor in ju -
ries or pro per ty damage.
Emission of Oil Mist
CAUTION
The non-OEM spa res mar ket of fers ex haust fil ters that are geo me -
tri cal ly com pa tible with Busch - va cuum pumps, but do not fea ture
the high re ten tion ca pa ci ty of ge nuine Busch-ex haust fil ters.
Increa sed risk of da mage to health.
In or der to keep the emis sion on the lo west pos sible le vel only ge -
nuine Busch-ex haust filters shall be used.
The oil in the pro cess gas is se pa ra ted to the grea test pos sible ex tent,
but not per fec tly.
CAUTION
Aspi ra tion of gas conveyed by the va cuum pump over ex ten ded pe -
riods can be harm ful.
The room into which the gas conveyed by the va cuum pump is dis -
char ged must be suf fi cien tly vented.
Safety
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