OIL DEGRADES BIOKEM

When oil is used in a machine, the oil will

degrade slowly during use over a period of time,

depending on the type of lubricant, operating

temperature, operating conditions and the

physical environment.

Lubricant degradation has negative effects on

system lubrication and for example, hydraulic

system pressures; these problems can result in

serious consequences for the equipment

performance and reduce reliability leading to

breakdowns.

New lubricants are a formulation of base oil and

chemical additives. Lubricant additives are

present to counteract the majority of ill effects

that contaminants cause.

Oil Refiners (Shell, Exxon-Mobil, etc.) produce

base oils that can be categorised into groups

which gives an indication of its oxidation

characteristics. Where longer life is required,

Group II, Group III and Group IV base oils are

used by lubricant manufacturers.

The Group of oil used is determined by the

Original Equipment Manufacturers recommendations to satisfy the OEM

requirements for equipment service and

warranty purposes.

Lubricant additives play a critical role in

preventing lubricant degradation. The additives

are essentially sacrificial in their role of

protecting the base oil because the additives

will degrade first while minimising any

degradation to the base oil molecular

properties.

After additive content is consumed by

operational forces, the integrity of the

hydrocarbon base oil becomes compromised

because it is no longer protected by additives.

At this point lubricant oxidation and the

consequent tell-tale discolouration

commences.

In short, the modern lubricant has been

designed and formulated to meet the harsh

operating environment of modern equipment.

Contaminants can unbalance the lubricant and can result in less than optimum

performance in its duty, increasing equipment

damage which can ultimately lead to

breakdowns.

Types of lubricant additives

include:

· Antioxidants (anti-oxidation)

· Antiwear agents

· Viscosity index improvers

· Rust/corrosion inhibitors

· Demulsifiers

· Extreme pressure additives

· Antifoam agents

· Detergents/dispersants

Additive depletion and

oxidation

Antioxidant additives are the key to extending

your lubricants remaining useful life by significantly limiting lubricant degradation from

occurring, but antioxidants are depleted in the

process.

Being sacrificial, antioxidants deplete first

before the base oil begins to oxidise and studies

have shown that once 70% of the antioxidant

additives in new oil have been depleted,

physical changes within the lubricant begin to

occur.

The resulting lubricant oxidation increases the

lubricant viscosity, Total Acid Number (TAN)

and the formation of sludge and varnish.

By monitoring the antioxidant content of

lubricant, Biokem detects additive depletion in

advance and prevents lubricant oxidation,

thickening and acid and varnish formation.

The additive depletion and oxidation reaction is

accelerated by a number of factors, primarily:

High operating temperatures

Moisture contamination

Particle contamination

High Operating temperatures

High operating temperatures in the form of

mechanical and thermal energy both produce

heat which will accelerate lubricant

degradation. Heat generated by operating

equipment is unavoidable, but excessive heat

will lead to increases in the consumption of

antioxidant additives. The rate of lubricant

oxidation doubles for every 10°C rise in

operating temperature above 100°C.

Moisture contamination

Water contamination adversely affects the

lubricants by acting as a catalyst for oxidation and

causes rapid additive depletion. Water will react

with many oil additives, fracturing the additive into

two or more chemical fragments. Water also

promotes rusting, corrosion and filter plugging.

Common sources of water contamination are heat

exchangers and seal leaks, condensation,

inadequate reservoir covers and temperature drops

that lead to dissolved water becoming free.

Particulate contamination

Particulate contamination occurs in many forms

within in-service oil, causing abrasive wear,

fatigue and erosion. Additional contamination

is evident whenever dirt particles circulate

through the system at high pressure and at high

speed.

Airborne dirt particle contamination is a major

contamination source. Light enough to float in

air these particles can be introduced in exposed

reservoirs as the oil level goes down. Oil

reservoirs with levels that change frequently are

most at risk to large amounts of dirt and

airborne contamination. This is commonly how

new oil delivered from oil companies becomes

contaminated.

Particulate contaminated lubricant provides reduced lubricating properties and increases friction that results in heat generation.

During oxidation, polymerisation causes sticky molecular structures, commonly referred to as sludge . Sludge is a resinous like substance

that is darker in colour and leaves deposits throughout the entire lubrication system. Sludge is often why lubricant will darken during its time in use.

With sludge molecules being microscopic in

size, the molecules are not removed by some

traditional filter systems. Combined with their

sticky molecular structure and corrosive effect,

lubricant sludge will directly affect the reliability

and efficiency of all systems it is found within.

Oxidation by-products cause more oxidation,

starting a cycle where the more by-products are

present, the faster oxidation accelerates.

Quickly the level of oxidation will reach a point

where the lubricant becomes destroyed by a

change in its molecular structure and must be

replaced with new oil.

Preventing lubricant

Oxidation

Rapid lubricant degradation will occur when the

additive quantity falls below critical level, at this

point the rate of oxidation will increase due to

the lubricant not having enough additives to

counteract oxidation.

The PROPEL Oil Management process includes

monitoring of active antioxidant additive to

determine the level of lubricant remaining

useful life (% RUL), moisture contamination and

particulate cleanliness level.

By lubricant condition monitoring and renewal,

additive levels do not deplete below critical

levels, preventing lubricant degradation and

waste. PROPEL Oil Management will renew

lubricant to as good as new specification (or

higher) before oxidation occurs, preventing

costly lubricant replacement.

PROPEL Oil Management – Professionally

Renewed Oil Prolongs Equipment Life.

To know more information, visit us

http://www.biokem.com.au/