What is spindle oil used for?

Specially designed with anti-wearing properties, spindle oil has been created for lubricating high-speed spindle bearings used in many different machine tools that require low-viscosity oils, such as precision grinders.

Spindle oil is made readily available by leading manufacturers including Shell, Mobil and Q8 and can be applied in a variety of ways. These application methods include misting, wick-feed, force-feed, drop feed, and hand oiling, as well as employing dedicated circulation systems to distribute the spindle oil.

Spindle oil commonly comprises a blend of 100 percent paraffin oil, specially selected for being severely hydrofinised, solvent refined and for having the best high-viscosity index available. On top of this, spindle oil is infused with special additives designed to imbue it with useful properties to help it perform its role effectively. These additives may be included to improve resistance to threats from oxidation or to deliver anti-wear capability to moving parts by reducing both friction and generated heat.

What is a spindle?

In machine tools, the term ‘spindle’ refers to a rotating axis of a machine, which typically has shaft at the heart. While the shaft is called a spindle, in shop-floor terminology it can also mean a complete rotary unit, encompassing not simply the shaft but its bearings too and all parts attached to it.

Machine tools sometimes have multiple spindles. A bench lathe, for example, has both tailstock and headstock spindles. However, the largest spindle on a machine tool is always the main spindle. When references are made to a single spindle, this is typically the one indicated.

Examples of spindles may include those on a lathe or a rotating-cutter on metalworking machine tools, such as drill presses and milling machines or woodworking machinery. There are wide variety of spindles, such as grinding spindles, machine tool spindles, electric spindles and low-speed spindles, as well as the two types of high-speed spindles, belt-driven and integral motor.

Performance benefits for equipment using spindle oil

There are many advantages to using a high-quality spindle oil when it comes to the operating performance machinery.

Spindle oil can work to minimise wearing, even under high load conditions, and this includes wear caused by spindle wobble when loads are imbalanced.

Equipment is also afforded a layer of robust protection from rust and other forms of corrosion with spindle oil. This specially developed lubrication also has exceptional demulsability characteristics. Demulsability refers to an oil’s capability of releasing water, which can be crucial when machinery is operating in the wet or humid conditions found in steel and paper mills due to the process fluids used, which are often water-based.

Spindle oil can greatly reduce build-up of varnish, sludge and other deposits, which can improve operating performance and avoid damage to machine parts. It can also provide enhanced oxidative and thermal stability, allowing equipment to function at the optimum level without needing down time to cool.

These properties of spindle oil lead to overall benefits, including the saving of both time and money when system maintenance needs are reduced and improving the longevity of both spindles and their bearings.