Heavy Duty Balanced Opposed Compressors - Ariel Corporation

FOR MODELS: JGZ AND JGU SECTION 4 LUBRICATION
• Anti-wear additives to help prevent metal to metal contact
• Viscosity improvers to improve the viscosity characteristics (primarily for multi-viscosity
oil)
• Pour point depressants to reduce the temperature at which the oil solidifies
• Anti-foam agents to help break up foam from air entrainment
Ash is not an additive. It is the heavy metal residue left over when the oil burns. Some of the
additives, such as the detergents, dispersants and anti-wear additives contain heavy metals
such as calcium (Ca), barium (Ba), magnesium (Mg), phosphorous (P), Zinc (Zn) or sodium
(Na). When the oil is burnt on hot parts of the engine, these heavy metals are left behind and
build a barrier that helps prevent wear such as valve seat recession.
Engine oil will work satisfactorily in the compressor frame and in many force feed systems in
gathering or transmission applications since viscosity is the most important aspect of compressor
lubrication. Although engine oil is generally not the best choice for compressor lubrication,
operational aspects such as previous experience, inventory control, or simplicity of maintenance
practices may outweigh the benefits of using a different type of oil.
Emulsion
One common problem with engine oil is the formation of emulsions in the compressor and/or
downstream equipment. The detergents in the oil allow the oil and water to mix. If the gas contains
enough water, it will mix with the detergents in the oil and emulsify. Usually the emulsions
will accumulate in the downstream equipment such as the scrubbers, but can also be found in
the cylinders and coolers.
To eliminate an emulsion problem, the emulsions must be completely removed and all equipment
thoroughly cleaned. Re-start the compressor using a R&O oil or some other appropriate
non-detergent based oil.
Used Engine Oil
If used engine oil is supplied for lubrication of the cylinders and packings, it must meet the listed
requirements for cylinder and packing lubrication. The oil must be appropriately filtered (ß5=10
and ß12=75 and have an ISO 4406 cleanliness code of 17:16:14 ). Oil viscosity must be monitored
and tested to be sure of adequate quality.
Gear Oil
Gear oils are formulated for use in gear boxes or other components where components make
frequent contact (boundary lubrication). The primary difference between these and other oils is
the extreme pressure (EP) additives. The EP additives are usually sulfur or phosphorous based
chemicals that bond with the iron and creates a material that has a low melting point. When the
components contact each other, the new material easily breaks away to reduce wear.
The reaction of forming the new material takes place at very high local temperatures. These
high temperatures are non existent in the compressor and therefore, the compressor does not
need gear oil. However, it is commonly used in instances where a high viscosity oil is required
such as ISO 460 or ISO 680.
If gear oil is used in the frame, it will be necessary to be sure the additives are not corrosive to
PAGE 4 - 6 7/09