The purpose of lubrication is to control friction and wear by the introduction of a friction-reducing film between moving surfaces in contact. Various substances can be used to lubricate, however, the most effective are Oil and Grease.
This is a general description of lubrication, which has many different aspects and variables, from the installation of a specific lubrication system to the type of lubricant that is being used.
What is a lubrication system?
An automatic lubrication system, also known as a Centralized lubrication system, is defined as the following: the controlled and precise amount of a particular lubricant that is delivered to a specific point at an exact time using the correct method, while the machine remains operational.
The structure of a lubrication system is composed of a pumping element, lubricating tank, electrical control device, dividers, distributors, and distribution lines (pipes and fittings).
The main purpose of lubrication
An efficient lubrication system reduces:
- Friction and wear of components
- Energy and lubricant consumption
- The generation of heat
- The noise from friction
- Corrosion damage and avoids the insertion of contaminants at the work site.
Furthermore, it ensures such advantages as a general increase in machine performance, improvement of working accuracy, an increase in a machines’ life, and the reduction of maintenance costs and downtimes.
Types of Lubrication Systems
Different types of lubrication systems have been designed and developed throughout the years, based on the specific requirement of machinery and the different industrial sectors.
1. Petroil System
In these types of the lubrication system, it is commonly used in the two-stroke petrol engines such as scooters and motorcycles. It is the simplest form of the lubricating system. For lubrication purposes, it does not have any separate parts like an oil pump.
But the lubricating oil is added to the petrol itself during filling in the petrol tank of the vehicle in a specified ratio. When fuel enters the crank chamber during engine operation, oil particles go down into the bearing surfaces and lubricate them. The piston rings, cylinder walls, piston pins, etc. are easily lubricated in the same way.
If the engine is allowed to remain unused for a considerable time, the lubricating oil separates off from petrol and starts to clogging of passages in the carburetor, occurring in engine start problems. Thus are the main disadvantages of this system.
2. Splash lubrication system
In these types of lubrication systems, the lubricating oil accumulates in an oil trough or sump. A scoop or dipper is made in the lowest part of the connecting rod. When the engine runs, the dipper dips in the oil once in every revolution of the crankshaft and causes the oil to splash on the cylinder walls.
This action affects engine walls, piston rings, crankshaft bearings, and large end bearings. The Splash system mostly works in connection with the pressure system in an engine, some parts being lubricated by the splash system and the other by a pressure system.
3. Grease lubrication system
In this system, the greasing pumps provide a proper amount of grease to the lubrication points. The main systems used for grease lubrication are Dual Line and Progressive systems.
4. Dual Line Lubrication Systems
The Dual Line system has a modular design that allows for simple configuration and expansion of the system, and it is suitable for industries with large machines and many lubrication points: iron and steel industry, cement plants, platforms, large cranes, and cargo handling equipment.
Dual Line Lubrication Systems are found in every industry which requires continuous duty operation. They are economical for systems having more than 20 bearing points and points can easily be added without redesigning the entire system.
When a blockage between the feed line and bearing occurs, it will not shut the system down; the remaining bearings will continue to be lubricated. There are positive lubrication indicators for each bearing point. Dual Line Lubrication Systems have the ability to positively displace a wide range of lubricants from light oil to grade-2 grease. Lubrication discharge volume at each bearing is fully adjustable even after start-up.
5. Progressive Lubrication Systems
A Progressive system distributes the flow of a grease pump into separate “progressive outlets” by the use of a progressive spool arrangement. The modular concept allows for the quick replacement of an element without interrupting the work cycle. It is suitable for small, medium, and large-sized machines that require total control of plant operations (machine tools, woodworking machines, presses, and textiles machines).
Series Progressive lubrication systems are most often used on medium-duty machinery and equipment. One advantage of this lubrication system is the ease of installation. Because pumps are connected to lubrication manifolds, some of which are modular, installation, modification, and maintenance can take place without the removal of the tubing.
In a Series Progressive lubrication system, progressive movement divider blocks operate in a pre-arranged sequence. This makes for easy monitoring of system operation through a moving indicator pin. Sequential movement of the pistons inside the divider block comes about by cyclic discharge from a lubricator. Fixed volumetric amounts of lubricant are displaced to each point connected to the lubrication system network
6. Oil lubrication system
The oil Lubrication system in total loss lubrication, oil, or fluid grease creates a thin oil film that protects parts. This is renewed at regular intervals by an automated lubrication system with an electric oil pump.
The main systems utilized in Oil lubrication are the Single-line system and the 33V system.
7. Single Line Resistance Lubrication Systems
The Single Line systems a simple and effective system that offers different solutions for a variety of application requirements. It is suitable for small machines operating in protected environments with a few lubrication points and space limitations: tools, woodworking machines, textiles machinery, and printing machines.
Single Line Resistance Systems are the simplest to operate and maintain. They are compact, economical, and ideally suited for equipment with closely configured bearing clusters or groups. The oil discharge is precisely controlled and delivered to each point while the machine is in operation. To keep reduce friction and wear, this lubrication system provides a clean film of oil between critical bearing surfaces.
Advantages to Single Line Resistance Lubricating Systems
- Easy to Design
- Simple to Operate
Suited for closely configured bearing clusters or groups
Single Line Resistance Systems are low-pressure oil lubrication systems. They are designed for light or medium machinery and can lubricate up to 100 points. When considering the type of lubricating system needed for your machinery, you can count on a Single Line resistance system to be compact, economical, and simple to operate and maintain.
The system precisely controls the discharge of oil to each delivery point while the machine is in operation, keeping a clean film of oil between critical bearing surfaces. The Single Line Resistance lubricating system will
- Keep friction and wear to a minimum
- Extend machinery life
- Increase production efficiency.
Automatic lubrication pumps are highly recommended over manual pumps. An automatic lubrication system is a safer, more exacting, and more reliable method of machine lubrication, thus providing a cost-effective alternative to manual systems. Automatic lubrication pumps are programmed to operate at preset interval times between lubrication cycles, eliminating the need for a machine operator to activate the process.
8. MQL (minimum quantity lubrication) system & Near dry machining
An innovative new technology that replaced traditional and pure oil fluid systems in a machining environment. fundamentally, a controlled compressed air stream carries minimal quantities of cutting oil in an “aerosol” format to the cutting surface by External or Internal (through the tool lubrication).
9. Semi-pressure System
It is the combination of a splash system and pressure system of the lubrication system. Some parts are lubricated by a splash system and some parts by a pressure system. Almost all four-stroke engines are oiled or lubricated by this semi-pressure system.
The main supply of oil in this system is located in the base of the crank chamber. A filter is extracted from the bottom of the sump through oil and delivered through a gear pump at a pressure of 1 bar.
Larger bearing ends are lubricated through a nozzle spray. Consequently, the oil also oils or lubricates crankshaft bearings, cams, cylinder walls, and timing gears.
The oil supply is measured with the help of oil pressure gauges. This system is less costly to install. This enables high bearing loads and engine speed to be applied than the splash system.
10. Air-Oil lubrication system
This system consists of a controlled air-oil stream utilized for both cooling and carrying small quantities of air-oil particles to the lubrication points. It is suitable for large machines in heavy industry and machine tools.
11. Recirculating oil system
The purpose of oil recirculation is to supply lubrication and provide cooling to bearings and gears. An electric pump ensures that an appropriate lubricant pressure is available in the mainline, where the oil flow is also measured and regulated.
12. Positive Displacement Injector lubrication systems
Positive Displacement Injector lubrication systems are driven by pressure generated by a centralized system lubricator. These systems are preferred for machinery which needs a very specific amount of lubricant to multiple points.
At regular intervals, injectors are alternately activated and deactivated. When the lubrication system reaches operative pressure, oil, and fluid greased discharges from the injectors.
13. Dry Sump System
The system in which lubricating of oil collects in the oil sump is known as a wet sump system as a pressure system. But the system in which the lubricating oil is not located in the oil sump is known as the dry pump system.
In this system, the vanes sweep the oil from the inlet to the outlet side. As the drum is applied in an eccentric manner, the volume between the drum and the casting continuously decreases, and the oil pressure at the outlet increases.
14. Wet Sump System
In this system, oil is transported to various engine parts with a sump strainer. In this wet sump system, oil pressure is of about 4 to 5 kg/cm2. After lubrication, the oil is carried back to the oil sump. In this case, the oil is present in the sump. Therefore, it is called a wet sump lubrication system.
The benefits of a wet sump system are its simplicity. And the oil is close to where it will be applied, doesn’t have a lot of parts to repair, and is relatively safe to build in a car.
15. 33V Lubrication System
The 33V system, a precise system for dosing that requires a specific amount of oil directly to the lubrication points. It is suitable for small, medium-sized machines such as woodworking machines, textiles machines, and presses.