Lubrication

Ball bearings are mechanical components in machines and equipment that enable the smooth and low-friction rotation of moving parts. When a bearing operates, the rolling elements and rings come into contact, which causes friction and heat. Lubrication reduces this friction by forming a film between surfaces, preventing metal-on-metal contact and overheating.

When selecting a lubricant, it is essential to consider the operating conditions, including temperature, speed, and potential exposure to contaminants. Additionally, it must be compatible with the bearing’s materials and other components that may come into contact with it.

Purpose of Ball Bearing Lubrication

Lubrication is essential for maintaining the proper operation and longevity of ball bearings. It also ensures the smooth and efficient operation of the equipment in which they are used.

Here are other significant purposes of ball-bearing lubrication:

  • Decreases risk of wearing
  • Hinders corrosion
  • Increases the bearing life
  • Lowers heat generation
  • Prevents metal-to-metal contact of the rolling elements with their raceways
  • Reduces the friction between the internal sliding surfaces of the bearing’s components

Types of Ball Bearing Lubricant

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There are two types of lubricants for lubricating ball bearings: oil and grease — each type has unique properties and advantages. Consequently, the most suitable lubricant for an application will depend on the operating conditions and bearing material.

Oil

Oil is a lubricant typically used in applications involving high speeds, loads, and temperatures. It delivers better heat dissipation and protection from wear and corrosion than grease. It also has a higher load-bearing capacity and oxidation resistance. Furthermore, oil can reach tight spaces that are difficult to lubricate with grease.

Grease

Grease is commonly used in lower-speed and lower-temperature applications. It is typically a combination of oil and a thickening agent for lubrication and keeping the lubricant in place. Grease lubricants are easy to apply and handle without constant monitoring. They can also separate contaminants and seal out dust and dirt.

Required Characteristics of a Lubricant

A ball-bearing lubricant must possess the following characteristics to provide adequate lubrication and bearing protection:

Low Friction and Abrasion

A lubricant that effectively reduces friction between the surfaces of a bearing will allow the parts to move smoothly and easily. Also, low abrasion properties can protect surfaces by minimizing the amount of friction caused by every movement.

High Thermal Stability

A lubricant with high thermal stability will withstand the bearing’s high temperatures without degrading or losing effectiveness. This is essential for components in high-temperature applications, such as engines and other machinery.

Good Thermal Conductivity

Good thermal conductivity will enable the lubricant to transfer heat away from the bearing and dissipate it into the environment. This helps maintain the temperature within safe limits, lowering the likelihood of overheating-related damage.

Strong Oil Film

A strong oil film protects the bearing from corrosion and other damage caused by exposure to contaminants. It can also serve as a thermal barrier and reduce heat transfer.

Non-Corrosive Properties

Lubricants highly resistant to corrosion can protect the bearing and its part surfaces from moisture damage. This will enable the bearing to operate correctly and last longer.

Stable Viscosity

A lubricant with stable viscosity will exhibit consistent resistance to flow over a broad range of temperatures, pressures, and shear rates. This characteristic ensures that the lubricant will provide the required film thickness and performance each time.

SPB-USA: The Leading Provider of Ball Bearings

High-quality bearings are essential for the proper functioning of equipment and machinery. Without them, even the best lubrication would not be able to maintain the performance and longevity of the component. At SPB-USA, we can provide precision bearings in various sizes and load capacities to suit different applications.

We hold ISO 9000, ISO 9001, and ISO 14001 certifications, guaranteeing that our products are of the highest quality and meet industry standards. Reach out to us today to learn more about our offerings or request a quote to start your next project with us!

LUBRICATING OIL AND GREASE

 LUBRICATING OILLUBRICATING GREASE
ROTATING SPEEDLOW MEDIUM HIGH SPEEDLOW MEDIUM SPEED
LUBRICANT EFFICIENCYEXCELLENTGOOD
COOLING EFFECTGOODNONE
TORQUECOMPARATIVELY LOWCOMPARATIVELY HIGH
LUBRICANT LIFELONGCOMPARATIVELY SHORT
LUBRICANT REPLACEMENTEASYDIFFICULT
LUBRICANT LEAKAGESHOULD NOT BE USED WHERE OIL LEAKAGE IS UNACCEPTABLELITTLE GREASE LEAKAGE
IMPURITIES FILTRATIONEASYDIFFICULT
SEALING EQUIPMENTCOMPLEXSIMPLE

GREASE FILLING VOLUME

SYMBOLFILLING VOLUME(%)OPERATING CONDITION
SPEEDLOAD
M70±10LOWHEAVY
S50±10LOWMEDIUM
G40±10MEDIUMMEDIUM
L30±10MEDIUMMEDIUM
Q25±5MEDIUMMEDIUM
K20±5HIGHLIGHT
X10±5HIGHLIGHT

NOTE: LIGHT LOAD ( 0.06Cr)
STANDARD LOAD ( 0.12Cr)


CRITERIA FOR LUBRICATING OIL SELECTION

OPERATING TEMPERATURE OF BEARING(°C)dnISO VISCOSITY GRADE OF
LUBRICATING OIL(VG)
MEDIUM LOADHEAVY LOAD/
SHOCK LOAD
-30~0UP TO PERMISSIBLE ROTATING SPEED15,22,3232,46
0~+60UP TO 1500032,46,68100
15000~8000032,4668
80000~15000022,3232
150000~5000001022,32
+60~+100UP TO 15000150220
15000~80000100150
80000~15000068100,150
150000~5000003268
+100~+150UP TO PERMISSIBLE ROTATING SPEED320

NOTE:

  1. IF HEAVY LOADS OCCUR AT LOW SPEEDS, A HIGHER VISCOSITY LUBRICATING OIL SHOULD BE USED.
  2. THIS TABLE IS FOR OIL BATH LUBRICATION SYSTEM AND RECIRCULATING OIL SYSTEMS.
  3. dn = BEARING BORE DIAMETER d(mm) ROTATING SPEED n(r.p.m)