Oilite

Last updated

Oilite is a brand of self-lubricating bearing that is made from metal alloys with pores that channel lubricants between the bearing itself and the shaft. It is manufactured from different types of material. Traditional Oilite is mostly made of copper with approximately 10% tin and up to 1% iron, while both Super Oilite and Super Oilite 16 are primarily made of iron with about 20% copper and, in the case of the latter, up to 1% graphite. Oilite is currently a registered trademark of Beemer Precision, Inc. [1]

Contents

History

One of the core engineers of Chrysler Carl Breer had an idea to pack graphite with metal in 1927, despite the fact that GM earlier failed to make a bushing from compressed copper and graphite. He hired engineer Sherwood and metallurgist Bill Caulkins, who succeeded in sintering copper, tin and graphite in a furnace without oxygen. [2]

Oilite was developed by Chrysler in 1930, [3] originally as bearings for water pumps and spring shackles, and without oil as the porous filter element in gasoline filters. Chrysler sold approximately 500,000 Oilite bearings in 1930 and approximately 2.5 million the next year. The Super Oilite was introduced in 1932. Overall sales of all Oilite material in 1932 was seven million; this rose to 18 million in 1933. Oilite was a profit center for Chrysler during this time. [3] In 2009, the Oilite trademark belongs to Beemer Precision. [4]

Composition

Oilite is manufactured using powder metallurgy so that tiny pores are present in the bearings. The pores are then vacuum impregnated with an oil to improve the material's bearing ability. [1] The material holds approximately 20% oil by volume. [5] The most common lubricant is SAE 30 oil. [6]

Due to the porous structure, machining Oilite poses a special situation. To machine Oilite, the cutting tool must be—and stay—sharp; therefore, tungsten carbide is often used. The sharp tool preserves the open-pore structure, because a dull tool would smear the material and close up the pores that are on the surface adjacent to the journal, which is where the lubrication needs to be. Reaming is not recommended, but can be done with an extremely sharp tool. Honing and grinding should not be performed on any surface that is in contact with the journal as these processes always smear the pores. [1]

Chemical composition of various Oilite grades [1]
Copper [%]Iron [%]Graphite [%]Tin [%]Other elements (max.) [%]
Oilite87.2–90.51 max.0–0.39.5–10.51.0
Super Oilite18–22Balance--2.0
Super Oilite 1618–22Balance0.6–1.0-2.0

Types

The different types of Oilite bearings vary by the metal alloy used, not by the type of oil with which they are impregnated. Many types of oil can be impregnated to facilitate various applications, such as high and low speed, high and low load, various temperature ranges, food-grade applications, and plastic compatibility. [1]

Oilite

Oilite material is the most widely used of all the types of Oilite bearing materials. Standards that encompass the Oilite material are: ASTM B-438-95A Grade 1 Type II, MIL-B-5687D Type 1 Grade 1, CT-1000-K26, SAE 841, and old SAE standard Type 1 Class A. [1]

Oilite Plus

Oilite Plus is the same bronze alloy as an Oilite, impregnated with turbine oil and fine particles of polytetrafluoroethylene (PTFE). This reduces the friction by approximately 17% versus standard Oilite material. This material is usually used in applications that exhibit mixed-film or boundary condition lubrication. Situations where this type of lubrication is encountered commonly include oscillating motions, slow speeds, intermittent use, pulsating loads, and uneven loads. [1]

Super Oilite

Super Oilite is an iron-based material that is harder, stronger, and cheaper than Oilite. It is rated for slower speeds, but it can handle higher loads. Common applications include farm equipment, winches, sheaves, conveyors, and pulleys. Applicable standards are: ASTM B-439-95 Grade 4, MIL-B-5687D Type 2 Grade 4, SAE 863, and old SAE standard Type 3. [1]

Super Oilite 16 is Super Oilite that has been heat treated to a hardness greater than HRC 50. This material is used for extreme loads and slow oscillating motions. Common applications include cranes, hoists, machine presses, and conveyors. The applicable standard is ASTM B-426 Grade 4 Type 2. [1]

Comparison

Physical and mechanical properties [1]
OiliteSuper OiliteSuper Oilite 16
Density [g/cm3]6.4–6.85.8–6.26.0–6.4
Minimum porosity [% oil by vol.]191915
Strength constant (K)26,50040,00060,000
Tensile strength [psi]14,00022,00032,000
Elongation [% in 1"]110.5
Yield strength in compression [psi]11,00022,00040,000
Maximum bearing limits [1]
MaterialPVStatic P [psi]Dynamic P [psi]V [ sfm ]
Oilite50,0008,0002,0001,200
Super Oilite35,00020,0004,000225
Super Oilite 1675,00050,0008,00035


Related Research Articles

A lubricant is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, transporting foreign particles, or heating or cooling the surfaces. The property of reducing friction is known as lubricity.

<span class="mw-page-title-main">Ball bearing</span> Type of rolling-element bearing

A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races.

Fluid bearings are bearings in which the load is supported by a thin layer of rapidly moving pressurized liquid or gas between the bearing surfaces. Since there is no contact between the moving parts, there is no sliding friction, allowing fluid bearings to have lower friction, wear and vibration than many other types of bearings. Thus, it is possible for some fluid bearings to have near-zero wear if operated correctly.

<span class="mw-page-title-main">Motor oil</span> Lubricant used for lubrication of internal combustion engines

Motor oil, engine oil, or engine lubricant is any one of various substances used for the lubrication of internal combustion engines. They typically consist of base oils enhanced with various additives, particularly antiwear additives, detergents, dispersants, and, for multi-grade oils, viscosity index improvers. The main function of motor oil is to reduce friction and wear on moving parts and to clean the engine from sludge and varnish (detergents). It also neutralizes acids that originate from fuel and from oxidation of the lubricant (detergents), improves the sealing of piston rings, and cools the engine by carrying heat away from moving parts.

<span class="mw-page-title-main">Bearing (mechanical)</span> Mechanism to constrain relative movement to the desired motion and reduce friction

A bearing is a machine element that constrains relative motion to only the desired motion, and reduces friction between moving parts. The design of the bearing may, for example, provide for free linear movement of the moving part or for free rotation around a fixed axis; or, it may prevent a motion by controlling the vectors of normal forces that bear on the moving parts. Most bearings facilitate the desired motion by minimizing friction. Bearings are classified broadly according to the type of operation, the motions allowed, or to the directions of the loads (forces) applied to the parts.

<span class="mw-page-title-main">Plain bearing</span> Simplest type of bearing, comprising just a bearing surface and no rolling elements

A plain bearing, or more commonly sliding contact bearing and slide bearing, is the simplest type of bearing, comprising just a bearing surface and no rolling elements. Therefore, the journal slides over the bearing surface. The simplest example of a plain bearing is a shaft rotating in a hole. A simple linear bearing can be a pair of flat surfaces designed to allow motion; e.g., a drawer and the slides it rests on or the ways on the bed of a lathe.

<span class="mw-page-title-main">Rolling-element bearing</span> Bearing which carries a load with rolling elements placed between two grooved rings

In mechanical engineering, a rolling-element bearing, also known as a rolling bearing, is a bearing which carries a load by placing rolling elements between two concentric, grooved rings called races. The relative motion of the races causes the rolling elements to roll with very little rolling resistance and with little sliding.

<span class="mw-page-title-main">Babbitt (alloy)</span> Metallic alloys

Babbitt metal or bearing metal is any of several alloys used for the bearing surface in a plain bearing.

<span class="mw-page-title-main">Gear oil</span> Lubricant used in vehicles and machinery

Gear oil is a lubricant made specifically for transmissions, transfer cases, and differentials in automobiles, trucks, and other machinery. It has high viscosity and usually contains organosulfur compounds. Some modern automatic transaxles do not use a heavy oil at all but lubricate with the lower viscosity hydraulic fluid, which is available at pressure within the automatic transmission. Gear oils account for about 20% of the lubricant market.

<span class="mw-page-title-main">Pillow block bearing</span> Bracket used to provide support to rotating shafts

A pillow block bearing is a pedestal used to provide support for a rotating shaft with the help of compatible bearings and various accessories. The assembly consists of a mounting block which houses a bearing. The block is mounted to a foundation and a shaft is inserted allowing the inner part of the bearing / shaft to rotate. The inside of the bearing is typically 0.025 millimetres (0.001 in) larger diameter than the shaft to ensure a tight fit. Set screws, locking collars, or set collars are commonly used to secure the shaft. Housing material for a pillow block is typically made of cast iron or cast steel.

<span class="mw-page-title-main">False brinelling</span>

False brinelling is a bearing damage caused by fretting, with or without corrosion, that causes imprints that look similar to brinelling, but are caused by a different mechanism. False brinelling may occur in bearings which act under small oscillations or vibrations.

<span class="mw-page-title-main">Galling</span> Form of wear caused by adhesion between sliding surfaces

Galling is a form of wear caused by adhesion between sliding surfaces. When a material galls, some of it is pulled with the contacting surface, especially if there is a large amount of force compressing the surfaces together. Galling is caused by a combination of friction and adhesion between the surfaces, followed by slipping and tearing of crystal structure beneath the surface. This will generally leave some material stuck or even friction welded to the adjacent surface, whereas the galled material may appear gouged with balled-up or torn lumps of material stuck to its surface.

Grease is a solid or semisolid lubricant formed as a dispersion of thickening agents in a liquid lubricant. Grease generally consists of a soap emulsified with mineral or vegetable oil.

<span class="mw-page-title-main">Gray iron</span> Alloy of iron and carbon

Gray iron, or grey cast iron, is a type of cast iron that has a graphitic microstructure. It is named after the gray color of the fracture it forms, which is due to the presence of graphite. It is the most common cast iron and the most widely used cast material based on weight.

<span class="mw-page-title-main">SAE steel grades</span> Standard alloy numbering system for steel grades

The SAE steel grades system is a standard alloy numbering system for steel grades maintained by SAE International.

Dry lubricants or solid lubricants are materials that, despite being in the solid phase, are able to reduce friction between two surfaces sliding against each other without the need for a liquid oil medium.

<span class="mw-page-title-main">Aerospace bearing</span> Aircraft part

Aerospace bearings are the bearings installed in aircraft and aerospace systems including commercial, private, military, or space applications.

Graphalloy is the trademark for a group of metal-impregnated graphite materials. The materials are commonly used for self-lubricating plain bearings or electrical contacts. They are proprietary materials owned by the Graphite Metallizing Corp. based in Yonkers, New York, USA.

<span class="mw-page-title-main">Spiral groove bearing</span> Hydrodynamic bearings using spiral grooves to develop lubricant pressure

Spiral groove bearings are self-acting, or hydrodynamic bearings used to reduce friction and wear without the use of pressurized lubricants. They have this ability due to special patterns of grooves. Spiral groove bearings are self-acting because their own rotation builds up the pressure needed to separate the bearing surfaces. For this reason, they are also contactless bearings.

Self-lubricating chains, also referred to as lube-free chains, are commonly found in both roller chain and conveyor chain varieties, with specialty self-lubricating chains also available. These chains utilize a bush made of an oil-impregnated sintered metal or plastic to provide continuous lubrication to the chain during drive, eliminating the need for further lubrication.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 Oilite (PDF), archived from the original (PDF) on 2011-08-20, retrieved 2009-12-17.
  2. ↑ https://www.allpar.com/threads/oilite-bearings-and-the-chrysler-amplex-division.227757
  3. 1 2 Curcio, Vincent (2001), Chrysler: The Life and Times of an Automotive Genius, Oxford University Press US, p. 485, ISBN   978-0-19-514705-6.
  4. ↑ Oilite bearings , retrieved 2009-12-17.
  5. ↑ SAE 841 (PDF), archived from the original (PDF) on 2011-02-06, retrieved 2009-12-17.
  6. ↑ McMaster-Carr catalog (115th ed.), McMaster-Carr, p. 1116, retrieved 2009-12-17.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.