Castrol Alusol SL 61 XBB

Castrol Alusol SL 61 XBB (formerly Alusol RBF) is a high-performance semi-synthetic metalworking fluid engineered to provide reliable machining performance, long fluid life, and consistent surface finish.
Formulated without boron, chlorine, or formaldehyde-releasing agents, it helps manufacturers meet modern environmental and waste management regulations while maintaining exceptional operational efficiency.

Its advanced additive package ensures superior lubrication, stable fluid performance, and extended tool life, all contributing to lower maintenance requirements and reduced operational costs.

Optimised Machining and Surface Finish

The semi-synthetic formulation of Castrol Alusol SL 61 XBB is designed to enhance tool life and surface quality, particularly when machining aluminium and aluminium alloys.
Its carefully engineered additives improve cooling and lubricity, helping reduce friction, minimise wear, and deliver a smoother, more consistent finish.

With low-foam properties under recommended water conditions, Alusol SL 61 XBB performs reliably in high-speed and high-pressure systems, ensuring smoother operation and better process stability.

Why Choose Castrol Alusol SL 61 XBB?

Castrol Alusol SL 61 XBB provides a combination of high-performance machining, environmental compliance, and cost efficiency.
Its semi-synthetic formula ensures stable fluid life, superior corrosion protection, and enhanced surface finish, while remaining boron- and chlorine-free for modern, sustainable manufacturing operations.

With Castrol XBB technology, this fluid helps manufacturers achieve cleaner machines, longer tool life, and more efficient operations, making it a reliable solution for demanding production environments.

Castrol Alusol SL 61 XBB is suitable for use in both large central systems and single sump machines, providing flexible performance for a variety of machining operations.

It is especially effective for aluminium and non-ferrous machining, but also performs well on ferrous alloys, making it versatile across aerospace, automotive, and general engineering applications.

The product’s excellent wetting and cleaning properties reduce coolant drag-out, helping to maintain cleaner machines and components while improving operational efficiency.

Castrol Alusol SL 61 XBB Lubricant Advantages:

• Boron-, chlorine-, and formaldehyde-releasing agent free – supports compliance with modern environmental and waste treatment regulations.

• Extended fluid life – reduces maintenance and machine downtime with stable, long-lasting performance.

• Low foam in recommended water conditions – ensures smooth, trouble-free operation in high-speed machining systems.

• Advanced lubrication package – enhances tool life and improves surface finish on aluminium and non-ferrous metals.

• Good wetting and cleaning properties – minimise coolant drag-out, keeping machines and components cleaner.

• Versatile application – suitable for a wide range of metals and machining operations, enabling product consolidation and simplified inventory management.

Please refer to the Technical Data Sheet

Recommended Dilutions:

Grinding 6-7 %
General Machining 6-8 %
Drilling 6-10%
Reaming and Tapping 6-10%
Broaching 6-10%
Water range 100 – 600 ppm CaCO3

To avoid product deterioration, always keep the container/drum tightly sealed. Store the product in a cool, dry place away from direct sunlight. Prevent exposure to frost and avoid water ingress. For optimum product stability, it is preferable to store Castrol Alusol SL 61 XBB indoors between 5°C and 45 °C / 41°F and 113°F.
For more details, please refer to the product safety data sheet.

This product was previously called Alusol RBF. The name was changed in 2015.

Download Technical Data Sheet

Download Safety Data Sheet

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