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Corrosion ControlHeat removal is one of the
most important functions of a metalworking fluid. Effective heat removal yields good tool life and dimensional accuracy of parts. Water has greater capacity for removing heat than oil. However, water alone
in contact with freshly machined metal leads to corrosion. Thus, corrosion is a problem faced by every manufacturer of water diluted metalworking fluids. The term "rust" applies only
to iron and steel. The term "corrosion" is more appropriate because this also includes nonferrous metals.
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Foam ControlFoam generally is considered to be an undesirable property in a metalworking fluid. Since most metalworking fluids have good cleaning
properties to help keep machines clean, they also foam when agitated. The quantity of foam that occurs, then, depends upon the chemical composition of a metalworking fluid product, the quality of the water
used for mixing, and the degree of agitation in the system. Top of Page
Importance of Water Quality on Water Dilutable Metalworking Fluid
Water is the major ingredient in a water-based metalworking fluid mix. It may amount to as much as 80-99% of the mix as used. Therefore, its importance in product performance cannot be ignored.
Corrosion, residue, scum, rancidity, foam, excess concentrate usage, or almost any metalworking fluid performance problem can be caused by the quality of the water used in making the mix. Untreated water
always contains impurities. Even rain water is more pure. Some impurities have no apparent effect on a waterbased metalworking fluid. Others may affect it drastically. By reacting or combining with
metalworking fluid ingredients, impurities can change performance characteristics. Therefore, water treatment is sometimes necessary to obtain the full benefits of water-based metalworking fluids. Top of Page
Rancidity of Water Dilutable Metalworking Fluids - Causes, Concerns, Controls, and Corrective Actions
Rancidity is one metalworking fluid challenge which demands immediate attention. Employees will not tolerate a foul smelling fluid and even if they would, the rust, loss of finish, poor tool life, and the
generally poor performance that may accompany rancidity can be major concerns in metalworking operations. Rancidity can be prevented by understanding the causes and by following a few simple
control practices. Top of Page
Paint RemovalThe advent of water-based chemical metalworking fluids has led to some concerns to their
use because they can cause paint to soften and peel off the machine. This is not true of all water-based metalworking fluids. Paint does come off some machine tools that are not properly painted, causing
concerns. Top of Page
Overview of Precoat Types and Methods for Wire DrawingIn order to optimize lubrication during dry wire
drawing, it is important to have appropriately cleaned wire surface, to use precoating or carrier coating when appropriate, and to use cost effective dry powder wire drawing lubricants. Hot rolled steel rod
has an oxidized surface and since this oxide is very abrasive, it must be removed to allow proper lubrication during wire drawing. The two primary methods of removing the oxide are chemical or mechanical
descaling. For chemical descaling, some of the more common acids used: are hydrochloric or sulfuric acids for carbon steel and a mixture of nitric and hydrofluoric acids for stainless steels. For mechanical
descaling, some of the methods employed are reverse bending, shot blasting with an abrasive media, or surface removal with abrasive belts or brushes. Top of Page
A
Suggested General Treatment Cycle for Skin Irritation in a Metalworking EnvironmentDermatitis or skin irritation in a metalworking plant can arise
from a number of causes, such as improper use of solvents or cleaners, abrasive hand cleaners, personal hygiene, changes in weather conditions, contaminated metalworking fluid, etc. But, as
mentioned, various other sources with the metalworking environment may cause skin irritation. In this regard, the following steps may be beneficial should such skin irritation occur. Though these steps have
been found to have favorable results, they are not meant to substitute for the consultation with a physician as a precautionary measure if or when necessary. Top of Page
Metalworking Fluid Controls For Water Dilutable FluidsProlonging the life of the metalworking fluid and optimizing its performance are very
dependent on the control of the metalworking fluid system. This control includes maintenance of the mechanical components, as well as the metalworking fluid and is as important as the selection of the proper
fluid. The problems that beset metalworking fluids in central system applications are the same as those in an individual machine sump, only the magnitude is greater. A program to accomplish this control
should include the following steps. Top of Page
Definitions of Analysis Terms for Water Dilutable Metalworking FluidsA summation of well defined
definitions on the more common terms used in the analysis of water diluted metalworking fluids. Those included in this paper are: Concentration, pH, Dirt, Volume, Free Oil, Total Oil, Tramp Oil, Bacteria
Count, and Total Alkalinity. Top of Page
The National Toxicology Program (NTP) Dermal Study on Rats and Mice with DiethanolamineEtna
Products, Inc. has long been committed to understanding the potential health issues associated with the raw material and finished products that it produces and to communicating those concerns to our
associates and customers. Consistent with this commitment to product stewardship, Etna is a member of the Independent Lubricant Manufacturers Association (ILMA) which has a Health and Safety Taskforce that
monitors the scientific data available regarding raw materials used to formulate lubricants. In addition to participating as an active member of the Health and Safety Taskforce, Etna is also a member of the
Metalworking Fluid Product Stewardship Group (MWFPSG SM), which is an
independent group of companies committed to product stewardship and to funding research designed to identify and to understand the raw materials used to formulate metalworking lubricants.
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The Influence of Metalworking Fluids on Common ElastomersThe selection of elastomers for the metalworking industry requires balancing the
elastomeric properties to suit the particular application. The key elastomer compounds to consider are the polymer type, the cure system, and the filter content. The primary metalworking fluid
components to consider are the oil, water, and alkalinity level. Many problems associated with elastomers in metalworking fluids are the results of contamination. Simulated service testing can be a useful
tool to judge the relative chemical compatibility of elastomers with the various types of metalworking fluids.
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Formicary Corrosion of Copper TubeFormicary corrosion is a problem that has been known for years, although relatively little work has been done to research this phenomena. Yamanchi, Motoyo, and
others have conducted the bulk of the work in the 1980s. Description of the Problem Formicary corrosion differs from typical copper oxidation in that the corrosion manifests itself as
an ant nest (i.e. formicary) pattern within the metal. The end result of this tunneling effect can be pin hole leaks in copper tube. Identifying formicary corrosion can in many instances be quite
difficult. Microscopy is the most prevalent technique, with a blue/lviolet or gray/brown appearance being an indication of formicary corrosion rather than the green/blue associated with more common forms of
copper corrosion. Since the formicary corrosion mechanism can take place over a period of time, finished product at the mill can pass inspection and fail months later.
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General Clean Out Procedure For Water Dilutable Metalworking FluidsA clean metalworking fluid performs better and lasts longer than a dirty fluid.
When recharging an individual sump or central fluid tank, a clean out of the tank is beneficial so that the fresh charge of metalworking fluid can perform with maximum efficiency. If not
removed, accumulated shop waste, metal swarf oil, mold growth, and pockets of bacteria cause deterioration of the fresh mix. In a new system, construction debris in the trenches and tanks, the chemical
waste, such as welding flux, from the assembly of steel trenches must be removed. If the trenches are constructed of cement a good cleaning helps to season them. The clean out, therefore, is
an essential first step. It insures that your metalworking fluid has an "even chance" to give maximum performance with a minimum number of problems. The following clean out
procedure should be used whenever possible, while no operators are producing parts. Top of Page
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