Directions for use
Dieselguard NB should be dosed into a suitable point in the cooling water system, after it has been thoroughly mixed with water. If the expansion tank is used then adequate circulation must be assured.
Sampling and testing
The WSS Test Kit provides the necessary equipment to carry out the control tests. Obtain a representative sample of the cooling water. Carry out the tests immediately after sampling (following the instructions given in the Test Kit) and log the results in Waterproof. The results should be sent to WSS as stated in the Waterproof instructions. Use the dosage chart overleaf to adjust treatment to obtain the optimum level. It is important that testing is carried out at least once per week, to ensure levels of treatment are correct.
Dosing and Control
Initial dosage for an untreated system is 2 kg/1000 litres of untreated distilled water. This will bring the treatment up to the minimum level of 1000 ppm. The dosage chart given below is for convenience in calculating the amount of Dieselguard required to bring the treament level to the suitable point between the minimum and maximum – this being 1440 ppm nitrite.
Normal nitrite limits: 1000-2400 ppm nitrite (NO2)
After a short period of use the operator will be able to easily determine the dosage required to maintain a proper treatment level.
Nitrite (as PPM NO2)
|
0
|
180
|
360
|
540
|
720
|
900
|
1080
|
1260
|
1440
|
1620 – 2400
|
Dieselguard NB kg/1000 ltr
|
2,88
|
2,52
|
2,16
|
1,80
|
1,44
|
1,08
|
0,72
|
0,36
|
0
|
0
|
N.B. Buffering agents in Dieselguard NB maintain pH values within suitable limits when the product is dosed as recommended.
The pH should be maintained between 8.3 and 10.0 by the treatment.
The engine manufacturer’s recommendations for water quality should always be complied with. Chloride levels should be as low as possible. Most engine manufacturers recommend a maximum of 50 ppm chlorides.
For this reason, Wilhelmsen Ships Service recommends to use distilled water as make-up.
Dieselguard NB is very water soluble. One kilogram of Dieselguard NB should be dissolved in 10 litres of hot water before adding it to the system.