Version 1.1.2 dated 2019-05-07
Page 304
Translation of the original instructions
Coolant lubricating
EN
co
olant
_G
B.
fm
OPTIMUM
M A S C H I N E N - G E R M A N Y
®
11.8.1 Inspection plan for water-mixed cooling lubricants
1)
The specified inspection intervals (frequency) are based on continuous operation. Other operational
conditions can result in other inspection intervals; exceptions are possible in accordance with Sections 4.4
and 4.10 of the TGS 611.
Editor:
Signature:
Company:
No.:
Date:
used cooling lubricant
size to be checked
Inspection methods
Inspection
intervals
Procedure and comment
noticeable
changes
Appearance, odour
daily
Find and rectify causes,
e.g. skim off oil, check filter, ventilate cooling
lubricant system
pH value
Laboratory techniques
electrometric with pH meter
(DIN 51369)
Local measurement method:
with pH paper
(Special indicators with
suitable measuring range)
weekly
1)
if pH value decreases
> 0.5 based on initial filing:
Measures in accordance manufacturer's rec-
ommendations
> 1.0 based on initial filing:
Replace cooling lubricant, clean cooling lubri-
cant circulation system
Usage concentration
Manual refractometer
weekly
1)
Method results in incorrect values with tramp
oil content
Base reserve
Acid titration in accordance
with
Manufacturer's recommenda-
tion
as required
Method is independent of tramp oil content
Nitrite content
Test sticks method or labora-
tory method
weekly
1)
> 20 mg/L nitrite:
Replace cooling lubricant or part
or inhibiting additives;
otherwise NDELA (N-nitrosodiethanolamine)
in the cooling lubricant system and in the air
must be determined
> 5 mg/L NDELA in the cooling lubricant sys-
tem:
Replacement,
clean and disinfect cooling lubricant circula-
tion system, find nitrite source and, if possi-
ble, rectify.
Nitrate/nitrite content
of the preparation water, if
this is not removed from
the public
grid
Test sticks method or labora-
tory method
as required
Use water from the public grid if there is
water from the pubic grid has
> 50 mg/l nitrate: Inform the waterworks
