Importance of different wear modes

There are four main wear modes: abrasive wear, adhesive wear, corrosive wear, and surface fatigue wear.  Which of these is the most critical?  The mechanism causing the greatest loss will obviously vary by application and is easily determined.  However, an unexpected an unexpected failure will usually come from a wear mechanism you have not planned for.

Wear Mechanisms:

• Abrasive Wear
  Abrasive wear is one of the largest causes of failure in industry. It can usually be avoided by preventing hard wear particles from entering the contact and making sure that the harder of the contacting surfaces is smooth.
• Adhesive Wear
  Adhesive wear is caused by small wear particles adhering to the surfaces and is one of the largest causes of failure.  It usually cannot be eliminated; however, it does have a high wear rate.
• Surface Fatigue Wear
  Fatigue damage will only accumulate when other wear rates are very low because otherwise the surface fatigued volume will be removed as wear particles.  This is less common than either adhesive or abrasive wear.
• Corrosive Wear
  This form of wear can usually be eliminated by controlling the chemical reactivity of the surfaces, the lubricant, and the humidity of the air.  Consequently, it is the least common mode of failure.

Source

Friction and Wear of Materials by Erneset Rabinowicz

Formalization of the engineering profession

Formal engineering training began during the industrial revolution; however, the gains in formal education did not occur in the same places that practical developments were made.  The professional engineers also began banding together in trade associations many of which exist to this day.  The locations with the most success in practical engineering seem to have adopted formal engineering training later than other areas.

The French were the first to start training engineers at a university; they were followed by the Germans and then the British.  In Britain most of the industrial advancements took place in the North while the engineering departments were started at universities in the south.

Professional engineering societies began around the same time as well.  The British, who were leaders in practical engineering, were the first to start professional societies and these societies often fractured based upon interdisciplinary disputes and personal snubs.  The Smeatonian Society of Civil Engineers was the first professional society founded in 1771 and still exists today.  Smeatonian, the founders last name, was added after his death.

Source: History of Tribology by Dowson

Farm manufacturer switches from bronze to plastic bearings

link:  http://www.designnews.com/article/388455-Plastic_Bearings_Picked_over_Bronze.php

Harriston Industries, a farm equipment manufacturer, is replacing some of its bronze bearings with graphite plugs with high performance plastic bearings.  The older bronze bearings were performing poorly in two environments:

1. When there were high loads due farm machinery being operated in abrasive volcanic soil, seizure occured.
2. Near the Atlantic ocean the high salt environment was leading to corrosion.

Replacing the bronze bearings with plastic bearings increased life by 500-600%.  The plastic bearings also cost 70-80% less than the bronze bearings.  Needless to say, Harriston is very pleased with the changes.

Improvements to machine tools during the Industrial Revolution

During the industrial revolution the number and quality of machine tools increased dramatically making mass production possible because interchangeable parts could be manufactured. There were four key factors which allowed these breakthroughs in machining and manufacturing.

• Increasing variety of machines:  In the mid 1700s the machines in use were similar to those used during the middle ages.  By 1850 nearly all the machining tools in use today had been invented.
• Machining accuracy: At the beginning of the industrial revolution a steam engine cylinder could vary by 3/8 inch in diameter.  By the end of the era the tools necessary for manufacturing precision ball bearings had been developed although the precision ball bearing itself had not yet been invented.
• Construction materials: In 1750 machining tools were primarily composed of wood.  In 1850 machinists equipment were mostly made of iron.
• Interchangeable parts: Muskets with interchangeable were first manufactured in Europe in 1785 and in America in 1798.

An example of the savings made possible by these advances can be seen in the production of pulley blocks for the British Royal Navy.  The production levels which previously required 110 skilled craftsmen could now be met by 10 unskilled laborers using 43 machines driven by a 30 horsepower engine.

Source: History of Tribology by Dowson

SKF opens new factory in Pune, India

link:  http://www.business-standard.com/india/news/skf-inauguratessolution-factory/375581/

SKF is opening a Solution Factory in Pune, India.  SKF’s Solution Factories bring all of SKF’s manufacturing capabilities together in one location for better customer service and access to a wider amount of application knowledge.  This is the 7th Solution Factory built by SKF with 10 factories currently under construction and a total of 34 more factories planned over the next two years.

Making business deals with Asian companies

link:  http://memagazine.asme.org/Articles/2009/October/East_West.cfm

In the October, 2009 issue of Mechanical Engineering there is an article about interactions between Asian and Western companies.  The difficulties arise because in the East a business deal is a personal agreement entered into with a handshake.  In the West a business deal is a legal contracted made with a signature.

The upside of this difference is that you can count on your Asian colleagues to loyal and keep their promises.  The downside of it is that you will need to continue to negotiate after the contract has been signed.

The Asian approach to a business relationship differs from the American one.  On the first contract the goal is to develop a relationship.  In subsequent phases of the relationship profit becomes more important.  Once you have developed a relationship, you are able to more easily win bids against your competitors.

Rush University Medical Center to include tribology facilities

link:  http://www.chicagotribune.com/business/chi-thu-notebook-rush-1105-nov05,0,7258615.story

Rush University is nearing completion of its new medical center which will open on November 16.  Amongthe facilities will be tribology, biomechanics, human motion analysis and implant retrieval laboratories.

RBC bearings purchases Lubron

link:  http://www.hydroworld.com/index/display/article-display/7870757037/articles/hrhrw/technologyandequipment/general/rbc-bearings_acquires.html

RBC bearings has purchased some assets  Lubron for $2.9 million.  Lubron makes self lubricated bearings for use in a wide variety of large scale applications such as bridges, power generation, and oil drilling.

Nanotribology merger between Nanosurf and CETR

link:  http://www.nanowerk.com/news/newsid=13198.php

Nanosurf and the Center for Tribology Research (CETR) have announced a strategic partnership to create nano-scale measurement devices.  Nanosurf produces scanning probe microscopes and CETR manufactures tribology and engineering test equipment.

Advances in tribology spurred by locamotives

During the early days of the railroad industry, there were two main tribology issues facing engineers:

1.  Would the wheels be able generate sufficient traction?

The engineers were unsure about whether the railway wheels would be able to start and stop the train as well as pull heavy loads without slipping.  Matthew Murray the first major railway designer fitted a fifth cogged wheel to his engines in order to deal with this worry.  The cogged wheel remained on railway engines for the next 22 years.

2.  How would lubricant be supplied to the bearings?

In the past, all machinery had been stationary making it easy to supply lubricant; however, a train did not operate inside a factory.  Furthermore, it was difficult for operators to monitor the bearings on a locomotive from their location inside the cars.  These problems spurred the development of self contained lubrication systems.

Source: History of Tribology by Dowson