Can you think of a reason ehy oil and grease, and not water, are used as a lubricant?
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Above statements does not mean that water is not a good lubricant. It’s just not a good lubricant for machinery and also other general purposes. For your information, our human body is using water as lubricant for our joints, eyes and also surrounding body structures.
Why is oil used as a lubricant instead of
Oil is viscous. So it help moving parts to move smoothly and it reduces wear and tear for rubbing parts..
Imagine rubbing your palms with water and rubbing with engine oil … The same feelings is applicable to engines..
First, the purpose of lubricant , is to lubricate, in other word, reduce fiction.
Lubricant reduces fiction by forming a film layer between surfaces, so instead of fiction between surface with surface, it will be fiction between surface with the lubricant.
It’s all about viscosity. If your oil is viscous, it will form a thicker film layer in between, thus increasing the lubricating strength. However, your machine will need more power to operate. Imagine, if you use water, the viscosity is very low, so only a very thin film layer in between, so the fiction didn’t reduce by much, not to mention it will boil at 100 degree Celsius when your machine need to be operation under high heat.
Water can reduce friction, true, but not as effectively as other lubricants.
In addition, it's fluidity makes it hard to keep in place(thus requiring it to be reapplied frequently), it evaporates easily when exposed to heat(machines that need lubricants produce a lot of heat), and water can be damaging to metal parts(leading to possibly expensive repairs).
Other reasons: Water freezes easily as well, so lower temperatures decrease it's effectiveness as a lubricant. Also, water expands when it freezes, which will cause damage to parts.
Why is oil used as a lubricant instead of
Oil is viscous. So it help moving parts to move smoothly and it reduces wear and tear for rubbing parts..
Imagine rubbing your palms with water and rubbing with engine oil … The same feelings is applicable to engines..
First, the purpose of lubricant , is to lubricate, in other word, reduce fiction.
Lubricant reduces fiction by forming a film layer between surfaces, so instead of fiction between surface with surface, it will be fiction between surface with the lubricant.
It’s all about viscosity. If your oil is viscous, it will form a thicker film layer in between, thus increasing the lubricating strength. However, your machine will need more power to operate. Imagine, if you use water, the viscosity is very low, so only a very thin film layer in between, so the fiction didn’t reduce by much, not to mention it will boil at 100 degree Celsius when your machine need to be operation under high heat.
Water can reduce friction, true, but not as effectively as other lubricants.
In addition, it's fluidity makes it hard to keep in place(thus requiring it to be reapplied frequently), it evaporates easily when exposed to heat(machines that need lubricants produce a lot of heat), and water can be damaging to metal parts(leading to possibly expensive repairs).
Other reasons: Water freezes easily as well, so lower temperatures decrease it's effectiveness as a lubricant. Also, water expands when it freezes, which will cause damage to parts.
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