Soluble Coolants

Castrol Alusol SL 51 XBB
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High performance soluble metalworking fluid


Castrol Alusol SL 51 XBB is a high performance soluble metalworking fluid which is free of boron, formaldehyde releasing agent and chlorine. It contains an additive package that may help to enhance machining performance and surface finish. It also provides excellent product stability which helps to lower the overall operational costs.

Alusol SL 51 XBB is suitable for large central systems and single sump machines.


Alusol SL 51 XBB is especially designed for machining of aluminum alloys. The product can also be used for machining
of ferrous alloys.

Cast Iron Low-Medium alloyed steel High-medium alloyed steel Aluminium alloys Magnesium alloys Yellow Metals
Grinding X X X X
Milling, turning (general machining) X XX XX XX X
Drilling X XX X XX X
Reaming, tapping X XX X XX X
Broaching X XX X

XX suggested core application

X possible application, please consult Castrol representative prior to use

  • Boron free to meet boron free waste requirements
  • Chlorine, formaldehyde releasing agent and nitrite free which may help you to fulfill aspects of legislative requirements and waste treatment requirements that specify that these chemicals are excluded
  • Extended fluid life can help reduce maintenance and machine downtime
  • Low foam in recommended water conditions (see details below)
  • Lubrication package designed to try to help to enhance tool life and improve surface finish on aluminium machining
  • Good wetting properties can help reduce coolant drag out and help deliver cleaner machine tools and components
  • Suitable for a wide range of materials and applications provides opportunity for product consolidation
Mineral oil 40% +
Concentration range 5-15%
Metal type Aluminum, Cast Iron, High alloy steel / Stainless steel, Low / Med alloy steel, Yellow Metal
Multi metals suitable Yes
Ester/EP additives Yes
Formulated without Chlorinated Paraffin Yes
Formulated without Boron Yes
Product type Metal Working Fluids
Applicable to these sectors Automotive Manufacture, Machinery, Metal Goods

Grinding 6-7%
General Machining 6-8%
Drilling 7-9%
Reaming and tapping 8-10%
Broaching 8-10%
Water range 100-800 ppm CaCO3


To avoid product deterioration always keep the container/drum tightly sealed. For optimum product stability, store between 5°C/41°F and 45°C/113°F in a cool, dry place away from direct sunlight. Prevent exposure to frost and avoid water ingress. It is preferable to store the product indoors.
For more details, please refer the product safety data sheet.


Download Technical Data Sheet

Download Safety Data Sheet

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