Machine Lubrication and Cutting Fluids PDF

MACHINIST PROGRAM - FIRST PERIOD MACHINE LUBRICATION AND CUTTING FLUIDS 150102h  MODULE OBJECTIVES 1.Describe the Health Hazards associated with Cutting Fluids 2.Describe the Characteristics and Functions of Cutting Fluid. 3.Describe Methods used to apply Cutting Fluids 4.Describe lubricat...

MACHINIST PROGRAM - FIRST PERIOD MACHINE LUBRICATION AND CUTTING FLUIDS 150102h  MODULE OBJECTIVES 1.Describe the Health Hazards associated with Cutting Fluids 2.Describe the Characteristics and Functions of Cutting Fluid. 3.Describe Methods used to apply Cutting Fluids 4.Describe lubrication schedules from a Manufacturer’s Specification  COOLANT HEALTH HAZARDS What You Should Know About Coolant Toxicity Coolant Health Hazards Dermatitis (irritation of the skin). Irritation of the throat from inhaling. Irritation caused by bacteria growing in the coolant. Any specific health concerns are best addressed by consulting the product’s WHMIS information. MACHINE LUBRICATION AND CUTTING FLUIDS Safe Application and Hazard Avoidance Always wear your personal protective equipment (PPE). If possible, apply barrier creams for protection of your skin. Use splash guards on machines to avoid spills and unintentional contact. MACHINE LUBRICATION AND CUTTING FLUIDS Coolant Handling Atomization Coolant that is atomized requires appropriate ventilation. PPE – Use a Respirator that ensure no droplets of coolant enter the bloodstream Control Rancidity Application of bactericide and detergents to reduce the potential for the coolant from becoming rancid. MACHINE LUBRICATION AND CUTTING FLUIDS Protection Read the MSDS (Material Safety Data Sheet) for all of the lubricants that you handle. Observe the warnings and recommendations found in the WHMIS documentation. Some chemicals build up in the body. Their effects may not become evident until many years later. MACHINE LUBRICATION AND CUTTING FLUIDS Protection Protect yourself from these potentially hazardous materials, create a barrier between you and the lubricant. Wear gloves and safety glasses as well as oil- or chemical- resistant boots. Keep all exposed skin covered. If oil misting, wear an appropriate safety mask. MACHINE LUBRICATION AND CUTTING FLUIDS WHMIS Label on NAIT Coolant MACHINE LUBRICATION AND CUTTING FLUIDS  CUTTING FLUID CHARACTERISTICS Characteristics of Cutting Fluids Transparency Low viscosity Resistant to Rancidity Non-Toxic Provides Corrosion protection MACHINE LUBRICATION AND CUTTING FLUIDS Purpose of Coolant They provide cooling to the workpiece and the tool They lubricate the work Provides chip control Apply rust inhibition to the surfaces Most importantly they extend tool life MACHINE LUBRICATION AND CUTTING FLUIDS Basic Facts There are two primary groups of metalworking fluids – 1) Non-water cutting fluids (Neat Oils) 2) water soluble (or Miscible). MACHINE LUBRICATION AND CUTTING FLUIDS CUTTING FLUID TYPES Types of Coolants and Cutting Fluids Three Main Categories are: 1. Straight Cutting Oils / None Mixed. 2. Emulsions (Soluble Oil). 3. Chemical (Synthetic) Cutting Fluids. MACHINE LUBRICATION AND CUTTING FLUIDS Active and Inactive Cutting Fluids. Inactive Straight Cutting oils Mineral oils are an example of straight oils. Mineral oils provide excellent lubrication, but are not very good at heat dissipation Mineral oils are particularly suited to non-ferrous materials such as aluminium, brass, and magnesium. MACHINE LUBRICATION AND CUTTING FLUIDS Active Straight Cutting Oils They are recommended for tough low carbon and chrome-alloy steels. Free Sulphur Based Oils that react well with cutting metals. They are widely used in thread cutting. MACHINE LUBRICATION AND CUTTING FLUIDS Chemical Cutting Fluids Non-toxic and non-hazardous Biodegradable Does not contain sulfur, chlorinated solvents, chlorine water, mineral oil or inactive fillers Description Effective on tough-to- Great for cutting, drilling, tapping, drill metals and alloys or threading metal components such as beryllium, molybdenum, stainless Ozone-Friendly formula contains steel and Stellite. no 1,1,1 trichloroethane MACHINE LUBRICATION AND CUTTING FLUIDS SOLUBLE OILS Soluble oils These emulsify into water and contain 60-85% mineral oil. As the least expensive fluid alternative, they are widely used as they offer good lubrication and have a great cooling capacity. MACHINE LUBRICATION AND CUTTING FLUIDS Emulsions (Soluble Oil) Emulsions, an emulsion is a dispersion of oil droplets in water. Soluble oils are mineral oils that contain emulsifiers. Emulsions (soluble oils) when mixed with water produce a milky white product. MACHINE LUBRICATION AND CUTTING FLUIDS Semi-synthetic fluids These emulsify into water and comprise 5-50% mineral oil. The heat transfer performance and cost of these fluids lie between synthetic and soluble fluids. MACHINE LUBRICATION AND CUTTING FLUIDS  Full Synthetic fluids With no mineral oil, they provide the best cooling performance and microbial control. Clear liquid increases visibility Elevated corrosion control. MACHINE LUBRICATION AND CUTTING FLUIDS COOLANT TESTING AND CALIBRATION  Refractometer Concentrations usually vary between 90 – 100 percent water to cutting fluids Refractometer Calibration to Zero  Example Refractometer Readings No Liquid Distilled Water Sugar NAIT ECOCOOL 712 is mixed with water for use. It may be used at concentrations ranging from 10:1 to 20:1. SELECTING CUTTING FLUIDS FOR SPECIFIC MATERIALS  Figure 13 - Cutting fluid chart. Material Tapping Drilling Turning Milling Machine Sulphur-based Soluble oil Soluble Soluble oil Steel cutting oil oil Alloy Steel Lard oil with Soluble oil Soluble Soluble oil mineral oil oil Aluminum Lard oil Soluble oil Soluble Soluble oil or Kerosene oil or Mineral oil Brass/Bronze Mineral oil with Dry or Soluble Soluble oil 20 % lard oil Soluble oil oil Cast iron Dry Dry Dry Dry CUTTING FLUID APPLICATION Coolant Delivery Systems Emulsion: a mix of water and oil (5-10% oil in the water) is the most common coolant media Oil : application of oil instead of emulsions. Active and Non-Active oils Compressed air delivery: used for chip evacuation but does not take away heat in a good way MQL (minimum quantity lubrication) Misting: compressed air with a minimum quantity of oil for lubrication Cryogenic coolant: a liquefied gas is used as coolant to maximize the cooling effect MACHINE LUBRICATION AND CUTTING FLUIDS Flood Application For all machining operations apply coolant directly on the tool Thru-Spindle Cutting Fluid Application Characteristics Good for cooling at deep machining condition. Excellent Chip evacuation © Her Majesty the Queen in Right of the Province of Alberta by the Minister of Advanced Education. 1998 Thru-spindle Misting System Air Infused with Coolants Characteristics Chip evacuation - Good Cooling levels – excellent Ease of viewing - excellent MACHINE LUBRICATION AND CUTTING FLUIDS  Misting Application Characteristics Less potential for contamination in tanks Ease of sight line High efficiency cooling affect Good chip evacuation © Her Majesty the Queen in Right of the Province of Alberta by the Minister of Advanced Education. 1998  MACHINE MAINTENANCE LUBRICATION Purpose of Lubrication in the Fight against Friction Supports a reduction of machine tool Wear Lubrication reduces friction. Supports corrosion resistance Lubricant supports machine tool seal health. Cleaning, Cooling, Prevents adhesion MACHINE LUBRICATION AND CUTTING FLUIDS Types of Friction This friction occurs as two different objects slide over each other. This friction occurs as two round objects roll around or on top of each other. This friction occurs as a pressurized fluid is restricted in its flow causing heat. MACHINE LUBRICATION AND CUTTING FLUIDS Sliding Friction Example The saddle of a lathe creates sliding friction as it moves along the ways, as well as a shaft rotating in a bushing. MACHINE LUBRICATION AND CUTTING FLUIDS Rolling Friction Example of Rolling Friction : A ball bearing meets Rolling Friction as it rolls around a bearing race. MACHINE LUBRICATION AND CUTTING FLUIDS Fluid Friction Fluid friction is the resistance one molecule in a fluid meets as it flows past another. MACHINE LUBRICATION AND CUTTING FLUIDS LUBRICANT PROPERTIES Properties of Lubricants 1. Viscosity 2. Flash point 3. Fire Point 4. Pour Point MACHINE LUBRICATION AND CUTTING FLUIDS  Figure 4 - Viscosity. Viscosity is measurement of a fluid to flow. at a specific temperature. Flows Quickly Flows Slowly Choosing Oils Based on Viscosity Too low an Oil Viscosity not provide for adequate protection and ultimately poor reduction of sliding friction. ( Like Olive Oil) Too high a Oil Viscosity will cause Fluid friction and elevated temperatures and also poor lubrication protection. ( Like Molasse’s. What affects Viscosity? - Temperature has the largest impact on Lubrication. - Pressure can increase a fluids viscosity MACHINE LUBRICATION AND CUTTING FLUIDS Flash Point , Fire Point, Pour Point Flash Point : The temperature where a fluids vapour will ignite when exposed to flame. Fire point : When a fluid burns steadily once ignited once exposed to flame. Pour Point : The lowest temperature where a lubricant will pour freely. This is important when working with tools that are exposed to poor weather. MACHINE LUBRICATION AND CUTTING FLUIDS Examples of Lubricating Oil Additives Anti-wear and EP Reduce friction and wear, and prevent scoring and seizure Agents Corrosion and Rust Prevent corrosion and rusting of metal parts in contact with the lubricant Inhibitors Detergents Keep surfaces free of deposits Dispersants Keep insoluble contaminants dispersed in the lubricant Friction Modifiers Alter the coefficient of friction Pour Point Depressants Enable lubricant to flow at low temperatures Seal Swell Agents Swell elastomeric seals Viscosity Modifiers Reduce the rate of viscosity change with temperature NAIT Specific Oil Requirements for Machine Tools LUBRICANTS: TYPES SELECTION APPLICATION Lubricant Types Petroleum Based - Petroleum-based oils incorporate molecules of hydrocarbons as well as additives such as paraffin, salts, and metals. Synthetic Oils - are so called because their lubricant bases are poly-alpha-olefins that contain no sulfur, metals or phosphorus and are synthesized into simpler chemical compounds. Animal By-product based - Lards , fatty acids from Cows, Sheep, Fish Vegetable based – Oils from vegetables like Canola, Olives MACHINE LUBRICATION AND CUTTING FLUIDS LUBRICANT SELECTION Lubrication Types Commonly Found In The Machine Shop Liquids - Oil that flows with viscosity of SAE 0 – 100, Semi Solids - Greases. Requires some form on injection system. Solids - Such as Metal elements ( Molybdenum, Graphite) MACHINE LUBRICATION AND CUTTING FLUIDS Basic Selection Factors Extreme Operating Pressure – Pressure changes the lubricant viscosity( the higher the pressure the higher the lubricant viscosity. Elevated Speeds– High rate of wear at high speeds require additives, and a low viscosity level Elevated Temperatures – Change of Viscosity due to heat, higher heat , higher viscosity selected. Environment - Dirt dust can cause friction. Poor selection can cause dust and dirt to attach to the component MACHINE LUBRICATION AND CUTTING FLUIDS  MACHINE TOOL LUBRICATING SYSTEMS Lubrication Systems Oil Can Wick Feed Drip Feed Splash Lubrication Circulating and Ring Oiler MACHINE LUBRICATION AND CUTTING FLUIDS Manual Lubrication Should have a company label attached (WHMIS) Not very reliable (depends on operator) Machine Tool Lubrication Application MACHINE LUBRICATION AND CUTTING FLUIDS Wick feed Oiling System. Uses a wick to allow just enough oil to lubricate part Where? Over-arm supports on Milling Machines. Recirculating Oiling System Oil is recirculated through a system and returned to a reservoir via a pump MACHINE LUBRICATION AND CUTTING FLUIDS Recirculating Oil Example Lathe Spindle oil Features Highly refined, low viscosity Oil with high pressure additives MACHINE LUBRICATION AND CUTTING FLUIDS Drip feed system Comes with a valve to regulate flow of lubricant Splash Lubrication Oil is splashed up within a closed housing to lubricate all internal components. Gear rotation will cause this affect Where is this system found? Lathe Headstock https://youtu.be/FOl_uRSp4gw Ring or Chain Type Oilers Ring revolves with the rotation of shaft lifting oil to where it is needed These are also known as oil slinger type lubrication systems Note : Closely monitor for a full reservoir MACHINE LUBRICATION AND CUTTING FLUIDS Grease Nipple Application Semi solid Lubricant used to reduce sliding friction on machine tools MACHINE LUBRICATION AND CUTTING FLUIDS LUBRICATION SCHEDULES Manufacturer’s Schedule. Manufacturer’s Lube Schedule Points to be lubricated. How often to lubricate. What kind of lubrication. Always lubricate as recommended by the manufacturer’s lube chart. Example Lubrication / Maintenance for a Manual Lathe MACHINE LUBRICATION and CUTTING FLUIDS https://youtu.be/itQOP_JjilM MACHINE LUBRICATION AND CUTTING FLUIDS END