::: SK ZIC :::

Definition of lubricant

Lubrication refers to the reduction of mechanical losses while making movement more harmonious by reducing frictional resistance through the supply of an appropriate substance (liquid or solid) between the frictional surfaces of 2 moving objects. Lubrication prevents damages to surfaces by separating the moving objects relative to each other by means of a membrane; the substance used in such situations is referred to as a lubricant.

Areas of application

Internal combustion engines (automobile, motorcycle, ship, train, etc.),
transmissions, industrial equipment (hydraulic equipment, compressors and turbines, etc.)
LUBRICATING AREAS
- AUTOMOTIVE ENGINE OIL
- GREASES
- INDUSTRIAL
- MARINE LUBRICANTS
- HYDRAULIC
- THF
- TRANSMISSION
- POWER PLANT
- LOCOMOTIVE
Lubricant function
- 1. Reduce friction / wear
  
  The foremost goal of lubrication is to reduce wear in machines by reducing friction.
- 2. Cooling
  
  Lubricants discharge the heat generated by friction and the lubrication system absorbs the heat.
- 3. Cleaning
  
  Lubricants prevent the entry of impurities such as carbonized substances from incomplete combustion, metal fragments, or dust.
- 4. Protection of machine (anti-rust)
  
  Lubricants protect the lubrication surface from rusting due to oxygen, moisture, or corrosive gas in the air.
- 5. Enclosure
  
  Lubricants seal the contacting section of the machine by preventing the leakage of gas injected into the cylinder or the entry of water or dust into the cylinder.
- 6. Dispersion of forces
  
  Lubricants uniformly disperse forces locally applied to frictional surfaces.
Accordingly, lubricants assist with the protection of equipment and extend its lifespan.
Lubricants can be thought of as similar to blood in the human body. A summary of the similarity between blood and lubricant follows.
- ACTIONS OF BLOOD
  
  Supplies nutrients
  
  Removes waste matter
  
  Antibacterial
  
  Assesses body condition
  
  Helps to prevent abnormality in blood and blood system
- ACTIONS OF LUBRICANT
  
  Prevents friction and wear
  
  Removes foreign matter
  
  Prevents rust and corrosion
  
  Assesses machine condition
  
  Helps to prevent abnormality in lubricant and closure of oil channel
Lubrication

In general, the lubrication condition is divided into the following three by the thickness of the oil film of the lubricant.
- Fluid-film Lubrication
  
  Also known as thick film lubrication or full lubrication.
- Boundary Lubrication
  
  Also known as thin-film lubrication or incomplete lubrication. Or when the amount of lubricating oil is not enough, the oil film becomes thinner. Lubrication is achieved by a thin molecular film adsorbed on the friction surface.
- Extreme Pressure Lubrication
  
  If a heavy load is applied or the temperature of the friction surface is high, the friction surface is likely to contact and be destroyed. In order to reduce the extreme friction, the lubricant is usually added with extreme pressure additives to chemically react with the metal surface to form an extreme pressure film.

Lubricant Composition

Lubricants are largely composed of base oils and additives.

Lubricant Class

There are several middle classes of lubricants currently in use, but generally they are divided into liquid lubricants,
semisolid greases, and other solid lubricants

1. Mineral oil

Mineral oils manufactured from crude oil are divided into three types according to the type of crude oil.

Paraffin Lubricant
Naphthine Lubricant
Mixed Lubricant

General Characteristics of Paraffinic and Naphthenic Lubricants

General Characteristics of Paraffinic and Naphthenic Lubricants
Classification	Paraffin	Naphthine
Specific gravity (S.G.)	Low	High
Viscosity index (VI)	High	Low
Pour point (PP)	High	Low

Mineral oil has a Viscosity-Index representing
the change of viscosity with temperature

Mineral oil has a Viscosity-Index representing the change of viscosity with temperature
Kinds	Viscosity inde
High viscosity index (HVI)	About 80 or more
Midpoint Index (MVI)	About 65 ~ 80
Low viscosity index (LVI)	About 65 or less

The oil that is used as the raw material of mineral oil-based lubricants is called base oil. Base oil is made by refining crude oil.

Common refined oil: Oil processed by acid, alkali, clay treatment, etc.
Solvent-refined oil: Oil refined using solvent, which has better oxidation stability than refined oil.
Hydrogenated Reforming Oil: Highly refined oil using catalyst under severe conditions of high temperature and high pressure. It has excellent performance in terms of oxidation stability compared to general refined oil.

2. Fatty oil

Vegetable oil and animal oil, used in aviation engines or in some applications for cutting, as raw materials for mixed oils and greases.

3. Mixed oil

4. Synthesized oil

Chemically synthesized lubricants from various raw materials are listed below.

Silicone oil: Used as precision machine oil, high temperature working oil and antifoaming agent.
Di-Ester oil: It is used as base oil of aircraft and jet engine, hydraulic oil and low temperature grease.

Lubricant classification

The classification of lubricants varies greatly depending on the criteria. Below is the classification of lubricants by engine / driveline / industrial use,
We represent our representative products belonging to the oil type.

Lubricant classification
Category	Application	Classification		Remarks	Our representative product	Industry standard
Non Off-Road	Engine	Car	Gasoline (PCMO)		X7	API SN Plus, ILSAC GF-5
			Diesel (Gasoline), (PCMO)	No aftertreatment device	Top, X9	ACEA A3/B3, A3/B4
			Diesel (Gasoline), (PCMO)	aftertreatment device	Top, X9	ACEA C1, C2, C3, C4
		Bus / Truck	Diesel (HDDO)	No aftertreatment device	X5000	API CI-4, ACEA E4
			Diesel (HDDO)	aftertreatment device	X7000, 9000	API CJ-4, ACEA E6/E9
			CNG		ZIC CNG	-
		Motor Cycle	2-stroke engine	Fuel / Lubricant Blend (Scooter)	ZIC M5	JASO FC/D, TC
		Motor Cycle	4-stroke engine	Engine / Transmission Simultaneous Lubrication	ZIC M9, M7	JASO MA, MB
		Select	2-stroke engine	Extra large ship	SuperMar Cyl	-
		Select	4-stroke engine	Medium / Large Ship	SuperMar TP	-
	DriveTrain	Transmission / Differential gear	Automatic transmission (ATF)	OEM-specific transmission design Different for each Product design required	DEXRON VI, XP-3, ATF 6	Dexron, Mercon, etc
			Manual / Differential Gear (MTF)	Compared to industrial gear oil Driving at high temperature	G-5, G-EP, G-FF	MT, GL-4, GL-5
			Other transmission	CVT, etc	CVTF Multi
		Shock Absorbing Oil (SAO)			Mando10, Mando7	-
Off-Road	Industrial Machinery / power plant/ Construction equipment	Hydraulics system	General purpose / low load	General Purpose Hydraulic Oil	SUPERVIS	-
			For heavy loads	Abrasion Resistant Hydraulic Oil	SUPERVIS AW/ZF	-
			Four seasons / heavy equipment	Hydraulic oil for heavy equipment	SUPERVIS X, ZIC VEGA	-
		turbine	Steam / gas	Water separation, oxidation stability, Sludge Prevention	TURBINE	-
		Industrial gear	Heavy load	Operation and water separation at low temperatures	SUPERGEAR EP	-
		cloud bearing	Grease	Yield stress lubricant (Including thickener)	Crown, Royal	-
	Other	Process oil (insulating oil, etc.), other than lubrication purpose (Functional Fluid)			-	-

Like PCDO (Passenger Car Diesel Oil) or HDDO (Heavy Duty Diesel Oil, heavy truck engine oil)For diesel engine oils, there are oils available depending on whether the aftertreatment unit is installed. PCMO stands for Passenger Car Motor Oil. It refers to engine oil for passenger vehicles, especially gasoline.

Two-stroke engines in motorcycle oil are designed to produce less smoke during combustion, while four-stroke engines are designed to satisfy the friction control characteristics.In the case of ship oil, the higher the content of fuel used, the higher the infectious value is used, and in the case of small vessels, land engine oil is usually used. ATF (Automatic Transmission Fluid, Automotive Gear Oil for Automatic Transmission) is different for each car manufacturer and needs a specific product design. Hydraulic oil and turbine oil of industrial oils require water separation and oxidation stability, and gear oils require extreme pressure performance.

Engine oil

Viscosity specifications

Complying with SAE (Society of Automotive Engineers) J300 regulations, there are low-temperature viscosity (CCS, MRV) and high-temperature viscosity (Kinematic Viscosity at 100°C, HTHS) conditions.

Viscosity specifications
Viscosity rating	Low temperature viscosity		Kinematic viscosity (cSt) @ 100°C		High temperature 26.1 shearing viscosity (HTHS, CP) @ 1500
Viscosity rating	Cranking viscosity (CSS, CP)	Pumping viscosity (MRV, cP)	Minimum	Maximum	High temperature 26.1 shearing viscosity (HTHS, CP) @ 1500
0W	6,200 at -35	60,000 at -40	3.8	ㅡ	ㅡ
5W	6,600 at -30	60,000 at -35	3.8	ㅡ	ㅡ
10W	7,000 at -25	60,000 at -30	4.1	ㅡ	ㅡ
15W	7,000 at -20	60,000 at -25	5.6	ㅡ	ㅡ
20W	9,500 at -15	60,000 at -20	5.6	ㅡ	ㅡ
25W	13,000 at -10	60,000 at -15	9.3	ㅡ	ㅡ
8	ㅡ	ㅡ	4.0	6.1	1.7
12	ㅡ	ㅡ	5.0	7.1	2.0
16	ㅡ	ㅡ	6.1	8.2	2.3
20	ㅡ	ㅡ	6.9	9.3	2.6
30	ㅡ	ㅡ	9.3	12.5	2.9
40	ㅡ	ㅡ	12.5	16.3	3.5(0W -40, 5W -40, 10W-40)
40	ㅡ	ㅡ	12.5	16.3	13.7(15W -40, 20W 16.3-40, 40 monograde) 21.9
50	ㅡ	ㅡ	16.3	21.9	3.7
60	ㅡ	ㅡ	21.9	26.1	3.7

Automobile gear oil

1. Viscosity specifications

Complying with SAE J3068 for low-temperature performance (Brookfield) and high-temperature viscosity (Kinematic Viscosity at 100°C) conditions..

Viscosity specifications
SAE Viscosity Grade	Maximum Temperature for viscosity of 150,000CP°C	Viscosity @ 100°C Minimum cSt	Viscosity @ 100°C Maximum cSt	Approx. EquivalentISO Grading
0W	-55	4.1	ㅡ	22-32
5W	-40	4.1	ㅡ	22-46
10W	-26	7.0	ㅡ	46-100
15W	-12	11.0	ㅡ	100-150
20W	ㅡ	7.0	<11.0	45-100
25W	ㅡ	11.0	<13.5	100
8	ㅡ	13.5	<18.5	150-320
12	ㅡ	18.5	<24.5	ㅡ
16	ㅡ	24.0	<32.5	320-680
20	ㅡ	32.5	<41.0	ㅡ
30	ㅡ	41.0	ㅡ	1000

2. Performance specifications

- API772: GL-1,2,3,4,5,6, MT-1
- US Military 772 : MIL-L-2105A, 2105B, 2105C, 21050, MIL-PRF-2105E

Specifications for industrial lubricant

Viscosity specifications

Complying with ISO (International Standards Organization) regulations and classified on the basis of kinematic viscosity at 40°C.

Viscosity specifications
Viscosity Grade	Kinematic viscosity at 40°C [mm² /s = cSt]
Viscosity Grade	Mid-point	Minimum	Maximum
ISO VG 2	2.2	1.98	2.42
ISO VG 3	3.2	1.98	2.42
ISO VG 5	4.6	4.14	5.06
ISO VG 7	6.8	6.12	7.48
ISO VG 10	10	9.0	11.0
ISO VG 15	15	13.5	16.5
ISO VG 22	22	19.8	24.2
ISO VG 32	32	28.8	35.2
ISO VG 46	46	41.4	50.6
ISO VG 68	68	61.2	74.8
ISO VG 100	100	90	110
ISO VG 150	150	135	165
ISO VG 220	220	198	242
ISO VG 320	320	288	352
ISO VG 400	460	414	506
ISO VG 680	680	612	748
ISO VG 1000	1000	900	1100
ISO VG 1500	1500	1350	1650

With industrial gear oil, the AGMA (American Gear Manufactures Association) divides this into AGMA 0-11 as follows in accordance with ISO VG (Viscosity Grade).

Viscosity specifications
ISO viscosity grade	Mid-point viscosity at 40°C ㎟/s1	Kinematic viscosity limits at 40°C ㎟/s1		Former AGMA grade equivalent2
ISO viscosity grade	Mid-point viscosity at 40°C ㎟/s1	min	max	Former AGMA grade equivalent2
ISO VG 32	32	28.8	35.2	0
ISO VG 46	46	41.4	50.6	1
ISO VG 68	68	61.2	74.8	2
ISO VG 68	68	61.2	74.8	2
ISO VG 100	100	90.9	110	3
ISO VG 150	150	135	165	4
ISO VG 220	220	198	242	5
ISO VG 320	320	288	352	6
ISO VG 460	460	414	506	7
ISO VG 680	680	612	748	8
ISO VG 1000	1000	900	1100	8A
ISO VG 1500	1500	1350	1650	9
ISO VG 2200	2200	1980	2420	10
ISO VG 3200	3200	2880	3520	11

NOTES

1The preferred unit for kinematic viscosity is mm/s, commonly referred to as centistokelcst).
2With the change from AGMA viscosity grade equivalents to ISO viscosity grade classifications, the designations S, EP, R and COMP will no longer be used as part of the viscosity grade nomenclature

Engine oil

1. Association specifications

API (American Petroleum Institute)
: Engine oil specifications made by API and divided into gasoline and large-scale diesel. The newer the specification, the more the reinforced oxidation stability, fuel efficiency, and durability, etc.
- Gasoline
  
  Begins with S as an abbreviation of ‘spark ignition,’ and followed by SA-SN. After using SA, SB, SC. SD, SE, SF, SG and SH, designations now being used include SJ, SL, SM, SN, SN Plus.
- Large-scale diesel
  
  CF4, CG-4, CH-4. CA4, C-4. CK-4(FA-4)
Begins with C as an abbreviation of ‘compression ignition,’ and is followed by CA-CK-4.
After having used CA. CB, CC. CD, CE. CF designations, CG-4, CH-4, C4, CJ-4, CK-4 have been enacted.

ILSAC (International Lubricant Standardization and Approval Committee, 2 89 standard and approval association)
: Engine oil specifications made by ILSAC composed of North American/Japanese automakers; includes GF1. 2, 3, 4 and 5. Fundamentally, they are specifications with fortified fuel efficiency performance added to API performance.

ACEA (Association des Constructeurs Europeans d'Automobilles)
: Engine oil specifications made by ACEA with emphasis on the characteristic durability and extension of the replacement interval of European vehicles compared to API or ILSAC. Generally, the specifications are amended on a 2-year interval.
Classified largely into 3 types depending on vehicle type with each type sub-classified according to performance and fuel efficiency (HTHSI/SAPS level).
- Passenger vehicle (gasoline/diesel) : A3/B3, A3/B4, A5/B5
  (although there were AI/BI specifications, it was abolished at the time of the ACEA
  amendment in 2016)
- Large-scale diesel : E4, E6, E7, E9
- For vehicles with built-in, post-processing devices (emission reduction device) : C1. C2, C3. C4, C5
2. OEM specifications

Apart from associations (API, ILSAC, ACEA), each automaker has its own in-house oil specifications with different specifications required for each OEM. Names of the specifications of the representative OEM are as follows.
- Passenger vehicles
  
  Mercedes-Benz: MB 229.1, 229.3, 229.31, 229.5, 229.51, etc
  Volkswagen: WW 50200, 504 00,505 00,505 01, 507 00
  General Motor: Dexos 1, Dexos 2
  Renault : RN 0700, 0710, 0720
- Large-scale diesel
  
  Mercedes-Benz: MB 228.1.228.3, 228.31.228.5.228.51, etc
  MAN : M 3275, 3277,3477, etc
  Volvo VDS-3, 4, 4.55, etc
  Cummins : Cummins 20078, 20081, etc
Automobile gear oil

Performance specifications

API specifications : GL-1, 2, 3, 4, 5, 6, MT-1
US Military specifications : MIL-L-2105A, 2105B, 2105C, 2105D, MIL-PRF-2105E

Automobile transmission oil

Performance specifications

Since there are many OEMs with long replacement intervals and recognized as a concept of component, there are no unified specifications per automaker as in the case of engine oil.
- General Motor: Dexron III, VI, etc.
  Ford : Mercon V, Mercon LV, Mercon SP, etc.
  Hyundai : SP III, IV , etc.
- ZE: TEEML 03D, 04D, 05L, 09, 11B, 16L, 170, 14A, etc.
  Chrysler : MS-1872, 5931, 9602, 10838, etc.
Specifications for industrial lubricant

Performance specifications

Oil types that belong to industrial oil are highly diversified and, as such, there are highly diversified performance specifications according to each oil type. Representative performance specifications of hydraulic oil, gear oil, and turbine oil are as follows:
- Hydraulic oil
  
  Denison : HF-0, 1, 2
  DIN 51524 : Part I, Part II, Part III
  ISO 11158 : HH, HL, HM, HV
  Cincinnati Machine(CM) : P-68, 69, 70
  Vickers : 104C, 35VQ25, 1-286-S, M-2950-S
  Us Steel : 127, 136
- Gear oil
  
  AGMA 9005 : E02, F17
  DIN 51517: Part I, Part II, Part III
  ISO 12925-1 : CKB, CKC, CKD, CKE, CKS
  US Steel : 224
- Turbine oil
  
  DIN 51515 : Part I, Part II
  General Electric: GEK-32568, GEK-107395
Trends in lubricants
- Improvement of fuel efficiency
  
  Striving to improve fuel efficiency by lowering viscosity and friction, as well as improving performance of oil in order to cope with the fuel efficiency regulations of each country.
- Long Drain Interval
  
  Striving for long drain intervals (replacement intervals) by fortifying the durability of the oil through performance improvement of volatility and oxidation stability of base oil and additives.
- Compatibility with post-
  processing device
  
  Reducing SAPS (Sulfated Ash, Phosphorous, Sulfur) contents in oil for the protection of performance and lifespan extension of post-processing devices (SGR, EGR, and DPF, etc.) introduced to cope with gas emission regulations.