Tuesday, July 24, 2018


5.2 TYPES OF AUTOMATIC LUBRICATION SYSTEMS
Automatic lubrication system generally fall into below categories:


OIL MIST SYSTEM
Mostly used in high-speed precision service
 Example:
  • ·         Grinding machinery
  • ·         Woodworking
  • ·         Air craft compressor


Working principle:
·         Injecting oil drop by drop into a stream of low pressure air to circulate just enough oil to wet the operating surface

 ORIFICE-CONTROL SYSTEM
  • ·         Use only oil as a lubricant with viscosity usually limited to 300 SUS or less
  • ·         Orifice used to control the amount of lubrication going into a bearing
  • ·         Best for small, single purpose machinery in a stable environment.
  • ·         Generally cheap, and simple to design and install.
  • ·         Additional point can be added without disrupting the original system
  • ·         Not suitable for area has vary temperature, viscosity change as temperature change viscosity
  • ·         Single broken line will disable complete system.


INJECTOR SYSTEM
  • ·         Can be used with oil and light greases,, usually limited to NLGI 1.
  • ·         Working principle: Quickly pressurized main system line so that the lubricant on the discharge end of a spool can be injected into a bearing.
  • ·         Pump capacity usually sized four times higher than the system’s requirement.
  • ·         Easy system to design
  • ·         Additional lubrication point can be added without disrupting original design.
  • ·         Broken line before any injector will disable complete system


     SERIES PROGRESSIVE SYSTEM
  • ·         Can operate with either oil or grease (suggested minimum viscosity 100 SUS, maximum NLGI 2)
  • ·         Provide positive displacement of lubricant by supplying each bearing with predetermined amount of lubricant before lubricating the next point.
  • ·         Main characteristic, system will disable when a line become plugged.
  • ·         Tamper resistant
  • ·         Complex design, expensive, require comprehensive engineering study & required high skilled maintenance personnel
  • ·         Additional point require re-design system




  • ·         Competitive system to series progressive, but can’t detect blocked line very well.
  • ·         Best choice to handle heavier lubricant for short runs.
  • ·         Much more tolerant of contaminant in the system as the feeder not easily blocked.
  • ·         Suitable for used in mining and steel mill application because the system proven successful in hostile environment.
  • ·         Working principle: Used two line running in parallel to deliver lubricant, pump supply flow at one line at a time, go to lubrication point then redirected to second line.
  • ·         Costly to install but advantageous in extremely long runs over several hundred feet in length.


    DUOLINE SYSTEM
  • ·         Innovative system which combine series-progressive and twin line system.
  • ·         This system extend for hundreds of feet the benefit of the series progressive system along the benefit of two lines.
  • ·         First used by Ford Motor Company in Europe (1970s) and then widely accepted in United States in short time.
  • ·         The system can be used with oil or grease and very reliable.
  • ·         Minimum oil viscosity is 100 SUS and maximum grease viscosity NLGI 2.


    PUMP-TO-POINT SYSTEM

  • ·         Simple system and easy to design
  • ·         Operates with a series of pumps that usually are driven off an eccentric cam that is powered by an electric motor
  • ·         Number of lubrication point limited by the number of pumps that can fit onto the eccentric cams
  • ·         Not suitable for location far from pump location and many lubricating point – expensive. Suitable for small, simple machine with under 12 lubricating point.
  • ·         Most system restricted to use oil as a lubricant


ZONE-CONTROL SYSTEM
  • ·         A system design for flexible machining centers.
  • ·         It is a series progressive system that utilizes a series of zero-leak solenoid valves that can be turned on to lubricate a particular station or cell of the machine.
  • ·         System can be configured to change the frequency of lubrication
  • ·         Can be used for oil or grease
  • ·         Minimum oil viscosity is 100 SUS and maximum grease viscosity is NLGI 1.


EJECTION SYSTEM
  • Single and multipoint ejection system ejects lubricant into the wear point or onto the wear surface such as:
  • ·         Chain conveyor links and bearings
  • ·         Roller chains
  • ·         Slides and guides
  • ·         Mold car conveyors and drives
  • ·         Open gears


LUBRICATION PROTECTION

Protection of lubricant to ensure its longevity and satisfactory performance by proper handling and storage of lubricants.
Protection practice to prevent:
a) Contamination of dirts
b) Contamination with excessive moisture or water
c) Exposure to extreme temperature


FIVE WAYS OF LUBRICATION PROTECTION


1. LOCATION AND PERSONNEL

  • ·         Provide clean and well-lighted room
  • ·         Provision for heating if expose to cold weather / environment
  • ·         Assign trained personnel for inventory and dispensing
  • ·         Provide clear label for each type of lubricant
 2. FACILITIES FOR HANDLING 

  • ·         Facility to ensure easy handling and proper storage arrangement
  • ·         Facility design so that various type of lubricant is mixed
  • ·         Handling equipment must keep clean and well maintained. 



3. LIGHTING
  • ·         Proper lighting ensure healthy and comfortable working environment
  • ·         Proper records and monitoring can be done
  • ·         Promote safety


4. BULK STORAGE

Benefits:
  • ·         Improved efficiency
  • ·         Reduced handling costs
  • ·         Reduced risk of contamination
  • ·         Simplified inventory

Expensive investment:
  • ·         Each products required its own dedicated system
  • ·         Bulk shipments can be done with tank trucks, car or tote bins.
  • ·         Products should be inspected visually for clarity and cleanliness and viscosity check prior to unload.

 5. FIRE PROTECTION

Enforce strict rules for safety:
  • ·         No smoking area
  • ·         Allow specific trained personnel to have access
  • ·         Allow the used of sparking or arcing producing tool only under the conditions of good ventilation
  • ·         Only allow minimum quantity of waste or wiping rags and stored in metal container
  • ·         Oil dripped is prevented or cleaned up properly


Good safety features:
  • ·         Suitable fire extinguishing equipment are available
  • ·         Clean area

LUBRICATION DEVICES AND SYSTEM



MANUAL LUBRICATION
  • ·         Grease gun
  • ·         Spraying type lubrication
  • ·         Apply by hand
  • ·         Compressed air / electrically powered lubrication equipment

AUTOMATIC LUBRICATION
  • ·         Efficient
  • ·         Reduce man-hours
  • ·         Precise control lubrication application
  • ·         Reduce material consumption

CENTRALIZED AUTOMATIC LUBRICATION SYSTEM
Centralized automatic lubrication system can be readily justified for the following reasons:
·         SAFETY
·         MORE EFFICIENT LUBRICATION
·         INCREASED PRODUCTIVITY
·         REDUCED OPERATING COST
·         BETTER HOUSEKEEPING
SAFETY
  • ·         No climbing around machinery
  • ·         No excess spillage around machines to cause slippery
  • ·         Difficult to access area due to location gas, fumes or height

EFFICIENT LUBRICATION
  • ·         Lubricant applied in small carefully controlled, correct amounts more frequently
  • ·         Prevent under-lubrication
  • ·         Prevent wasteful over-lubrication

INCREASED PRODUCTIVITY
  • ·         Increased machine life
  • ·         Lubrication done automatically while machine is running
  • ·         Reduced downtime

REDUCED OPERATING COST
  • ·         Reduce maintenance labour cost
  • ·         Less friction – lower power requirement
  • ·         Fewer man-hours for manual lubrication

BETTER HOUSEKEEPING
  • ·         Machine and surrounding area remain clean of excess lubricant


                                                     PROPERTIES OF  LUBRICANTS


There are various properties of lubricants such as Viscosity Index Oiliness,Volatility, Flashand Fire Point, Cloud Point And Pour Point, Emulsification, Carbon Residue, Aniline Point, Saponification Number.


                                                                    Viscosity Index
The viscosity index (V.I.) of an oil is a number that indicates the effect of  temperature changes on  the  viscosity  of  the  oil.  A  low  V.I.   signifies   relatively  large  change  of  viscosity   With changes of  temperature.  In  other  words,  the  oil  becom es extremely thin at high temperatures and extremely thick at low temperatures. On the other hand, a  high  V.I.  signifies  relatively  little  change  in viscosity  over  a  wide  temperature  range






      Motor Oil Characteristics

·         Oil Viscosity/SAE •Ease which oil flows •S.A.E  Rating  (Society of Automotive Engineers)
·         Service Rating/API
·         Oil Quality •A.P.I. (American Petroleum Institute)
·         Other Fluids & Lubricants


                                                                Asperities – Formidable
All surfaces, no matter how smooth they may appear to the unaided eye, when sufficiently magnified are rough and uneven. This  unevenness is know as asperities


                                        Three Common Types of Wear as a Result of Friction




                                                                             Tribology


Since the late 1960’s the field of Tribology – the study of friction, wear and lubrication in fluid systems - has  developed sophisticated tests to gain much knowledge into  the effects of friction and ways to reduce friction in order  to reduce wear, heat and particle contamination.




                                                                        The Problem


Friction and heat cause the destruction of asperities resulting in metal particles interrupting the oil film between two surfaces generating more particles. These particles react with moisture, impurities and lubricant additives creating corrosive acids that further pit the surface creating new asperities. These acids oxidize the lubricant, accelerate wear and rapidly deteriorate the functions of the lubricant resulting in the 3-common wears in the fluid system.





                                                       FLUID MANAGEMENT

                     Apply four essential components in a fluid management program. 


·                                                                                             Selection and purchase of lubrication 




·                                                                                 Lubrication monitoring during use





·                                                                           Lubricant maintenance using processing  






·                                                                                                    Refortification techniques 






·                                                                                          Disposal of the spent lubricant.  




5.2 TYPES OF AUTOMATIC LUBRICATION SYSTEMS Automatic lubrication system generally fall into below categories: OIL MIST SYSTEM Mo...