What is Tribology and how can lubricant selection improve leaf chain performance?
Traditionally, lubrication needed for a forklift chain application could be fulfilled by using all round, off-the-shelf lubricants and chosen generally based on experience. Nowadays, demanding environments dictate that the forklift mast chain runs faster, longer and at different temperature environments rendering the traditional approach almost obsolete. Modern lubricants need to meet exacting specifications that are specific to each forklift chain application.
So, what is tribology? – Officially it’s the study of friction, lubrication and wear and in recent years has become the byword for lubricant selection. Each lubricant has its own tribological system.
Identifying TheTribological System
Identifying the tribological system of an application takes place before the selection of a lubricant which includes factors involving motion, speed, temperature, load and the working environment.
Once identified, the lubrication engineer can use chemical analysis to determine the correct lubricant that will optimize the performance of the chain according to application
The first factor of the tribological system involves the type of motion. What type of movement is involved?
Speed is the second tribological system parameter. Speed of chain element bearings can be broken into three general ranges: fast, moderate and slow.
All lubricants have specific temperature ranges for optimal performance. Many lubricants have a broad operational temperature range; however, some lubricants are more suited for lower temperatures.
Load is an important factor affecting the chain lubricant requirement. A light load may indicate the application is sensitive to frictional torque, and therefore a lubricant would have to be selected to minimise the fluid friction while still providing protection from metal-to-metal friction. A heavily loaded forklift chain, which could require specific additives to help protect from pitting, galling and extreme wear.
The last parameter of the tribological system is the forklift’s operating environment. If the environment includes moisture or water, the lubricant must provide good anticorrosion properties as well as resistance to water washout or contamination. If the application operates in a vacuum or partial vacuum, the atmospheric pressure of the application must be within the operational limits of the lubricant and above its vapor pressure at the operating temperature.
Multipurpose lubricants cannot provide satisfactory service in current demanding environments. Lubricant performance must be optimized to meet the increasing demands of modern industry.