How to choose a lubricant: oil, grease or spray for the job

Choose the lubricant according to the job it has to do: oil where parts slide and the film needs to be renewed, grease where the product has to stay put (bearings, joints, pins), spray where you need to work quickly or in hard-to-reach spots, penetrating oil where a screw or pin is already seized. In the collection you'll find 400 ml aerosol cans, bottles from a few millilitres up to 1 litre, 25 L jerrycans and 150-180 kg drums: the pack size also needs choosing with care, because if you use little, an oversized pack wastes product.

Types

• Engine oil: for the internal combustion engines of machines and equipment. The right grade is the one specified by the engine manufacturer, not the one you already have in stock.
• Hydraulic oils: for systems and machines that transmit force through a pressurised fluid. Here what matters is the viscosity specified by the machine.
• Special oil and universal cutting oil: for machining operations, where the oil lubricates and cools both tool and workpiece.
• Industrial lubricant: a product for the mechanical parts of machines and systems; the data sheet says which applications and temperatures it is suited to.
• Lubricating grease: a protective, multi-purpose version for bearings, joints and guides, where oil would run off.
• Chain lubricant: designed to cling to the links and stay there while the chain runs.
• Multi-purpose or silicone spray lubricant: for hinges, slideways, locks and light mechanisms. Silicone is suited to places where you don't want greasiness.
• Penetrating release oil: penetrates rusted threads and frees seized parts. Like the Ultra Sblock NPT Sigill 400 ml rapid penetrating spray.
• Oil-film protectant: leaves a thin film on the metal and protects it from rust, for example on tools and equipment kept in storage.

The collection also includes tools for applying the product, such as the Pressol lever grease gun.

How to choose for the job

If you're not sure whether you need oil or grease, think of it this way: if the point is enclosed or hard to refill (a bearing, a joint) go for grease; if the product has to flow and be renewed (a chain, an open slideway) go for oil.

Features to look at

• Product type: on the data sheet you'll find entries such as multi-purpose spray lubricant, universal cutting oil, penetrating release oil, protective multi-purpose grease. It's the first thing to read, before the brand.
• Content and pack size: the aerosol cans are 400 ml, but there are also 15, 100, 200, 250 and 300 ml sizes and 1 litre. Drums go up to 150-180 kg. Choose according to how much you use, not just the cost per litre.
• Density: in the collection it ranges from about 0.75 to 0.94 kg/l at 15 °C. It's used to convert litres into kilograms; it doesn't tell you whether the product lubricates better. The lower values are typical of the more fluid products, the higher ones of the thicker oils.
• Appearance, colour and odour: clear liquid, straw-coloured, amber, brown. These are descriptions, not quality indicators. Odour (characteristic or odourless) matters if you work in enclosed spaces.
• Compatibility: materials (plastics, rubbers), temperatures and working environment. If the product has to be suitable for food use, it is stated on the data sheet.

For quantities such as viscosity, check the data sheet of the individual oil: it varies from product to product and has to be compared with what the machine manufacturer specifies.

Common mistakes

• Using penetrating oil as a lubricant. It frees the screw, but it doesn't leave a lasting film: after using it, properly lubricate the part.
• Spraying over dirt. The product mixes with dust and old grease and acts as an abrasive paste. Clean first.
• Overfilling a bearing. More grease doesn't mean better: the excess heats up and can push the seal out.
• Mixing different greases without checking. Some greases are not compatible with each other and lose their properties. If you change type, clean the point.
• Using just any oil for the hydraulic system. The viscosity specified by the manufacturer must be respected.

Frequently asked questions

Which is better, oil or grease?

Oil where the product has to flow and be renewed, grease where it has to stay put on the point. For bearings, joints and pins grease is almost always used.

Does multi-purpose spray replace oil and grease?

For light jobs and general maintenance, yes. For heavily loaded points or those that work for long periods you need the grease or oil specified for that component.

How often should I lubricate?

According to the machine's maintenance intervals. If you don't have them, ask the manufacturer or the AMES technicians: repeating the operation at random doesn't help.

How do I dispose of used lubricant?

As special waste, never down the drain or onto the ground.

You'll find all the products in the Lubricants collection. If you don't know which one to choose for your machine, ask for a quote or advice from the AMES technicians.