Cold heading is preferred over metal cutting operations for this process due to its ability to generate less waste while producing large quantities. However, while more efficient – cold heading machines are not immune to the output of oil and smoke buildup.
Learn how oil mist collectors aid in reducing exposure to smoke and oil mist in cold heading processes below.
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How does Smoke and Oil Mist Occur in Cold Heading?
Cold heading, also known as cold forming, is the manufacturing process where metal wire is fabricated into fittings and fasteners without heat and at high speed. The amount of smoke and oil mist will depend on several factors – the type of metal used, the diameter of the stock, the speed, the specific process being performed, and the type of lubricant applied.
Oil lubricants are used to prevent excess wear and tear of the dye in the cold heading process. When lubricants are used, heat becomes vapor – resulting in smoke and oil mist. Mist is generally defined as a liquid droplet that is or less than 20 microns in diameter. Smoke is much smaller in comparison as it can range from 0.07 to 1 micron in diameter, and can be either liquid or solid.
Identifying Oil Mist Problems
Some believe that if they are unable to see the mist, it must not exist. This point of view fails to realize the issues that submicron mist can pose in the shop environment. Moreover, the presence of mist can be realized by the other senses. There is typically a distinguishing odor when oil mist is present.
Depending on the lubricant used, the smoke and oil mist can also accumulate and become sticky to touch – adhering to the shop environment and the machines it houses. Regular cold heading operation without adequate industrial air filtration will eventually lead to the visibility of smoke and oil mist – on the floors, walls, lights, and equipment.
The Risk of Long-Term Exposure to Smoke and Oil Mist
Simply put, conventional methods of managing air quality around cold heading machines do not effectively mitigate the risks associated with long-term exposure to smoke and oil mist. Using masks, mechanical vents with primary filters, and regular clean-up of the shop environment may be able to mitigate the impact of minimal exposure to smoke and oil mist. But they are unable to properly manage the air quality when it comes to long-term exposure to smoke and oil mist.
Maintaining industrial air quality is essential when it comes to the health of shop personnel, your equipment performance, and ultimately – the success of your business.
Slick or sticky shop environments and poor air quality due to smoke and oil mist can result in severe health issues for shop personnel. Slick environments can lead to more injuries related to slip and fall accidents. People that are exposed to oil mist can experience irritation of the eyes and skin, a burning sensation in the mouth and throat, as well as fever, rapid heart rate, shortness of breath, headache, and vomiting. More severe health issues related to long-term exposure to smoke and oil mist can also lead to skin and respiratory diseases, as well as cancer.
Improper air filtration of smoke and oil mist will also deteriorate machine life over time- ultimately contributing to increased operational and maintenance costs. It is for these reasons that proper air filtration for cold heading is essential to ensuring the health and safety of shop personnel and equipment.
Mist Collectors for Cold Heading Machines
Mist concentration in cold heading processes will differ in comparison to other machining processes. Cold heading processes create a high amount of oil smoke, and exclusively used electrostatic mist collectors up until 15 years ago. The primary issue with the use of electrostatic mist collectors is that they did not efficiently collect the oil in the smoke, as the oil is an insulator. This resulted in the electrostatic cells to decrease in efficiency, and led to increased cleanings of the electrostatic oil mist collector (as often as twice a week for heavy loading, and once a month on lighter loading).
The primary purpose of an oil mist collector for cold heading machines is to remove smoke and oil mist droplets from entering the shop environment. However, certain mist properties will impact mist collector performance.
OSHA states that the limit for airborne metalworking fluids (coolants) by 8-hour exposure, from 5 mg/m³ for mineral oil and 15 mg/m³ for other coolant types. NIOSH recommends lower at 0.4 mg/m³.
Increased temperature can result in condensation – impacting droplet size and how it is collected. For instance, when water-based coolants are utilized – water will evaporate at higher temperatures and lower humidity – resulting in smaller droplet sizes.
The type of mist will also impact mist collector performance. As different types of mist droplets will have varying surface tension and viscosity properties, this will affect the mist collector’s ability to collect and drain the fluid. Moreover, if a mist contains many dry particles (swarf) then they will also need to be removed in addition to the coalescing (collection) of the droplets.
Aeroex Mist Collectors for Cold Heading Processes
Innovation in oil mist collector technology over the past 15 years has introduced a more efficient solution that requires less maintenance. Today, most cold heading operations have converted to mist collectors that use fibre beds to deal with smoke and oil mist.
Canadian-based Aeroex Technologies’ line of Mist-Fit and ARO mist collectors are made with cold heading applications in mind. Aeroex’s mist collector solutions reduce consumables by utilizing mechanical progressive filtration, quality fibre bed technology, and HEPA filtration in tandem to provide superior smoke and oil mist collection performance that ensures clean air and reduced maintenance costs. In fact, maintenance is low with filter life spanning up to 3 years.
The Aeroex team of engineers and specialists will evaluate your unique needs, and can recommend an industrial oil mist collector solution that will limit exposure to oil and coolant mist as the result of cold heading processes. Get in touch with a representative today and eliminate the negative effects of long-term exposure to smoke and oil mist on your shop personnel and equipment.
