[0001] The present invention relates to a metalworking fluid, and more particularly a metalworking
fluid comprising a blend of synthetic (water-based) and semi-synthetic (oil-based)
components.
[0002] Metalworking fluids have many applications within industry, such as destructive metalworking
(chips of metal are produced, such as in milling or grinding) and deformation metalworking
(chips of metal are not produced, such as in rolling), as well as more specific applications
such as wire drawing. The metalworking fluids are used to cool and lubricate during
metalworking operations. Such fluids typically comprise an oil-based (oleaginous)
component, an aqueous component and emulsifier. The products are typically supplied
as concentrates which are diluted with water by the user. In use the continuous water
phase provides cooling, whilst the oil droplets plate out on metal surfaces to form
a lubricating film between the metal being worked and the tool.
[0003] Mixing otherwise immiscible aqueous and oil-based components requires the use of
emulsifiers to create an emulsion. Surfactants are typically used as emulsifiers,
with sufficient surfactant included to ensure that the emulsion forms completely.
Ideally there should be no residual immiscible components, and the emulsion should
be stable, such that the individual components do not separate out during storage
or use.
[0004] Historically metalworking fluids were soluble oils, typically comprising a majority
of mineral oil together with other components such as emulsifiers, corrosion inhibitors
and other additives. The oil was mixed with water to form an emulsion. As performance
requirements have become more demanding the proportion of additives has increased,
such that the oil content has reduced to 10-50wt% (excluding water). Such products
are known as "semi-synthetic" metalworking fluids. Known disadvantages of semi-synthetic
fluids include limited long-term stability and also adverse reactions between anionic
emulsifiers and cations in the water, which can lead to insoluble reaction products
generating deposits on machines and in filters, and can also deplete the level of
emulsifier, potentially leading to phase separation.
[0005] An alternative type of metalworking fluid is known as a "fully synthetic" fluid,
all components of which are soluble in water. The lubrication is provided by compounds
whose solubility in water is inversely proportional to temperature, such that at room
temperature they are soluble in water, whereas as the temperatures typically encountered
at the metalworking surface due to friction (80°C or more) they plate out to form
a lubricating film on the metal surface. Examples of such compounds are polyelkylene
glycols (PAGs), which are copolymers of ethylene oxide and propylene oxide.
[0006] The absence of reactive anionic species and an emulsified oil phase means that fully
synthetic products do not have any sensitivity to cations, nor do they form problematic
deposits with the consequent risk of phase separation. However they have their own
inherent problems due to their design. PAGs are strong surfactants, and the absence
of an oily residue on surfaces following evaporation of the water phase can lead to
corrosion problems. Additionally, the fact that lubrication is only provided above
a certain temperature (that at which the PAG is no longer fully soluble in water,
known as the "cloud point") means that at the start of a metalworking operation, before
friction has raised the temperature of the working surfaces sufficiently, no lubrication
is provided and damage to the surfaces may occur, particularly if the worked metal
is soft.
[0007] A similar problem occurs in conditions where surface temperatures are lower throughout
the process, in which case lubrication may generally be insufficient. This is particularly
the case in wire drawing applications, where a wire is drawn out of a die onto a capstan
and differential speeds cause the wire to slip on the capstan. The slipping wire is
lubricated, but because the contact pressure between the wire and the capstan is low,
the temperature may not rise high enough to cause the PAG to become insoluble. Consequently
lubrication is minimal, leading to a reduction in surface quality of the wire, and
poor or inconsistent slipping can cause the tension in the wire to increase resulting
in breakage of the wire.
[0008] In order to overcome these specific difficulties in wire drawing, it has been known
to to provide an aqueous solution of a fully synthetic product and then add to this
dilution a small amount of a soluble oil concentrate. This can improve the slip of
the wire, but it is difficult to monitor and control the relative proportions of the
active materials in the final fluid, which can be critical for successful performance.
[0009] It is an object of the invention to overcome some of the above disadvantages of both
synthetic and semi-synthetic fluids, and to provide a metalworking fluid which can
provide lubrication at all working surface temperatures and hence throughout the process,
as well as long-term stability.
[0010] Accordingly in a first aspect the present invention provides a metalworking fluid
concentrate comprising
(A1) 1.5 - 4.0wt% of a blend of a C8-C30 alcohol with a fatty acid ester R1CO2R2 where R1 is a C8-C30 acid residue and R2 is a C1-C12 alcohol residue
(A2) 1.5 - 4.0wt% wt% of a surfactant
(A3) 0.5-1.8wt% of additives selected from anti-gelling agents, foam control agents,
anti-wear additives, extreme pressure additives, pH buffers and biocides
(B1) 6 - 15wt% of an amine which is water-soluble at room temperature
(B2) 2 - 5wt% of a corrosion inhibitor which is water-soluble at room temperature
(B3) 5 - 15wt% of a compound selected from ethylene oxide or propylene oxide block
copolymers, ethylene oxide or propylene oxide random copolymers, ethylene oxide or
propylene oxide polymer esters and ethylene oxide ethers
(B4) 60-80wt% of water.
[0011] We have found that the composition of the invention provides excellent lubrication
in a wide range of applications including wire drawing, gives low deposits during
use and also has excellent long-term stability.
[0012] Throughout this specification the term "water-soluble" means that no more than 0.5wt%
of a compound is left undissolved in the aqueous phase when the compound is either
dissolved in water or reacts in water to form a salt which itself dissolves.
Component (A1)
[0013] Component (A) is a blend of a C
8-C
30 alcohol with a fatty acid ester R
1CO
2R
2 where R
1 is a C
8-C
30 acid residue and R
2 is a C
1-C
12 alcohol residue.
[0014] The alcohol is preferably a C
12-C
24, more preferably a C
14-C
20 alcohol, with C
16 being particularly preferred.
[0015] In the fatty acid ester, the acid residue R
1 is preferably a C
12-C
24 hydrocarbyl group, more preferably C
14-C
20, with C
16-C
18 being particularly preferred. The alcohol residue R
2 is preferably a C
1-C
8 hydrocarbyl group. Examples of the alcohol of which R
2 is the residue are methanol, 2-ethylhexanol, ethanol, butanol and isotridecanol.
[0016] Amounts of component (A1) range from 1.5 to 3.7wt%, preferably from 1.8 to 3.5wt%
and more preferably from 2 to 3wt%.
Component (A2)
[0017] Component (A2) is a surfactant, which means anything capable of acting as an emulsifier.
[0018] The surfactant is preferably nonionic, and may have a hydrophobic portion of C
10-C
28, preferably C
14-C
24, and more preferably C
16-C
20 chain length, optionally modified with 1-20, preferably 4-16 and more preferably
6-12 units of a hydrophobic polyalkoxylate chain, plus a hydrophilic portion comprising
a polyalkoxylate. Alternatively the nonionic surfactant may comprise a C
10-C
28, preferably C
14-C
24 and more preferably C
16-C
20 fatty acid esterified with a polyfunctional alcohol.
[0019] The surfactant may alternatively be anionic, in which case it may have a hydrophobic
portion of C
10-C
28, preferably C
14-C
24, and more preferably C
16-C
20 chain length, optionally modified with 1-20, preferably 4-16 and more preferably
8-10 units of a hydrophobic polyalkoxylate chain, and capped with an anionic group
such as carboxylate, sulfate, sulfonate, sulfosuccinate or phosphate, with carboxylate,
sulfonate and phosphate being preferred, of which carboxylate and phosphate are most
preferred.
[0020] A further list of possible surfactants includes C
16 -C
18 fatty alcohol ethoxylates - with an ethoxylation range of 0-9 moles (fatty alcohol
polyglycol ethers); C
16 -C
18 fatty alcohol ethoxylate and propoxylate; C
6/C
8/C
16 -C
18 alkyl polyoxyethylene ether carboxylic acids with a 2 to 9 mole ethoxylation range;
alkyl ether ethoxylate mono phosphate esters - alkyl chain C18 , with a 2 to 5 mole
ethoxylation range; ethoxylated oleine with a 6/9 mole ethoxylation range; and polyethylene
glycol esters of C
16 -C
18 fatty acids. Combinations of various surfactants may be particularly advantageous.
[0021] Other possible surfactants include alkanolamides, alkylaryl sulfonates, alkylaryl
sulfonic acids, amine oxides, amide and amine soaps, block copolymers, carboxylated
alcohols, carboxylic acids/fatty acids, ethoxylated alcohols, ethoxylated amines/amides,
ethoxylated fatty acids, ethoxylated fatty esters and oils, ethoxylated phenols, fatty
amines and esters, glycerol esters, glycol esters, imidazolines and imidazoline derivatives,
lignin and lignin derivatives, maleic or succinic anhydrides, methyl esters, monoglycerides
and derivatives, naphthenic acids, olefin sulfonates, phosphate esters, polyalkylene
glycols, polyols, polymeric (polysaccharides, acrylic acid, acrylamide), propoxylated
& ethoxylated fatty acids, alcohols or alkyl phenols, quaternary surfactants, sarcosine
derivatives, soaps, sorbitan derivatives, sucrose and glucose esters and derivatives,
sulfates and sulfonates of oils and fatty acids, sulfates and sulfonates ethoxylated
alkylphenols, sulfates of alcohols, sulfates of ethoxylated alcohols, sulfates of
fatty esters, sulfonates of dodecyl and tridecylbenzenes, sulfonates of naphthalene
and alkyl naphthalene, sulfonates of petroleum, sulfosuccinamates, sulfosuccinates
and derivatives, tridecyl and dodecyl benzene sulfonic acids.
[0022] Particularly preferred classes of nonionic surfactants are fatty alcohol alkoxylates,
polyethylene glycol esters, sorbitan esters and sorbitan ester alkoxylates.
[0023] Particularly preferred classes of anionic surfactants are alkyl ether carboxylates,
sulfosuccinates, sulphonates, alkyl phosphate esters and alkyl ether phosphate esters.
[0024] Combinations of surfactants may also be particularly advantageous.
[0025] Amounts of component (A2) range from 1.5 to 3.7wt%, preferably from 1.8 to 3.5wt%
and more preferably from 2 to 3wt%.
Component (A3)
[0026] Types of additives include glycols and glycol ethers to prevent gelling, foam control
agents, anti-wear additives, extreme pressure additives, pH buffers and biocides.
[0027] Biocides include, but are not limited to, formaldehyde releasing agents including
ortho-formal, hexahydratriazine and derivatives, methylene bis morpholene, oxazoladine
and derivatives, isothiazolinones and derivatives and iodo propyl butyl carbamate-fungicide.
[0028] Extreme pressure additives include, but are not limited to, chlorinated and sulfurized
fatty acids and esters, polysulfides, organophosphates, and neutralized phosphate
esters.
[0029] Examples of foam control agents include, but are not limited to, methyl silicone
oil, fluorosilicone oil, polyacrylate and the like.
[0030] The total amount of all components (A3) ranges from 0.5 to 1.8wt%, preferably from
0.6 to 1.5wt% and more preferably from 0.7 to 1.4wt%.
Component (B1)
[0031] Component (B1) is an amine which is soluble in water at room temperature. Examples
include aminomethylpropanol (AMP-95), 3-amino-4-octanol, diglycolamine (DGA), monoethanolamine
(MEA), monoisopropanolamine (MIPA), butylethanolamine (NBEA), dicylclohexylamine (DCHA),
diethanolamine (DEA), butyldiethanolamine (NBDEA), triethanolamine (TEA), and methylpentamethylenediamine.
[0032] Amounts of component (B1) range from 6 to 15wt%, preferably from 6.5 to 10wt% and
more preferably from 7 to 8wt%. Alternative preferred ranges are from 9 to 12wt%,
preferably from 10 to 12wt%.
Component (B2)
[0033] Corrosion inhibitors are chemical compounds which, when added at low concentrations,
inhibit the corrosion of metals and alloys. They generally function by either forming
a passivation layer on the metal, or by inhibiting either the oxidation or reduction
part of the redox corrosion system (anodic and cathodic inhibitors), or by scavenging
dissolved oxygen. Different metals typically require different corrosion inhibitors.
Examples of corrosion inhibitors include alkylphosphonic acids, alkali and alkanolamine
salts of carboxylic acids, undecandioic/dodecandioic acid and its salts, C
4-C
22 carboxylic acids and their salts, tolytriazole and its salts, benzotriazole and its
salts, imidazoline and its salts, alkanolamines and amides, sulfonates, alkali and
alkanolamine salts of naphthenic acids, phosphate ester amine salts, alkali nitrites,
alkali carbonates, carboxylic acid derivatives, alkylsulfonamide carboxylic acids,
arylsulfonamide carboxylic acids, fatty sarkosides, phenoxy derivatives and sodium
molybdate.
[0034] A further list of possible corrosion inhibitors which can be used includes polycarboxylic
acid compounds, polymeric phosphoric acid compounds and benzotriazole. but are not
limited to amine/alkali salts of short chain carboxylic mono acids, di acids and tri
acids, short chain acidic phosphate esters, including alkoxylated esters, semi-succinate
half esters, amide-carboxylic acid salts, fatty amides, and amine and alkali sulphonates
or their derivatives. Inhibitors for yellow metals include benzotriazole or its derivatives
and tolutriazole or its derivatives. Suitable esters include, but are not limited
to TMP (trimethylol propane) mono, di and tri esters of C
8 - C
18 fatty acids, glycol esters of predominantly olely fatty acids, methyl or isopropyl
esters of predominantly olely fatty acids or triglycerides, natural triglycerides,
such as rapeseed, and modified natural oils such as blown rapeseed.
[0035] Preferred cast iron corrosion inhibitors include undecandioic/dodecandioic acid and
its salts. Preferred yellow metal corrosion inhibitors include tolytriazole sodium
salts. Preferred aluminum corrosion inhibitors include octanephosphonic acid and citric
acid monohydrate.
[0036] Amounts of component (B2) range from 2 to 5wt%, preferably from 2.1 to 4.5wt% including
ranges from 2.2 to 2.8wt% and from 4.0 to 4.5wt%, with the higher range being for
applications involving copper. The amounts and types of corrosion inhibitor required
for different metals are well understood by those skilled in the art.
Component (B3)
[0037] Component (B3) is a compound having a solubility in water which varies inversely
with temperature. As stated above it is selected from ethylene oxide or propylene
oxide block copolymers, ethylene oxide or propylene oxide random copolymers, ethylene
oxide or propylene oxide polymer esters and ethylene oxide ethers. Examples of such
compounds are the reaction products of alcohols and alkylene oxides commonly known
as polyalkylene glycols (PAGs). Polyalkylene glycols are well known as lubricants
in many applications including metalworking fluids due to their high thermal and oxidative
stability, excellent lubricity and high film strength/load capacity, as well as good
anti-wear properties and shear stability.
[0038] PAGs are random or block copolymers containing ethylene oxide (EO) and propylene
oxide (PO) units. The cloud point, defined as the temperature at which the PAG in
a 1% aqueous solution comes out of solution, is dependent primarily on the EO content,
which can range from 10% to 80%, and is typically between 20% and 75%. The cloud point
may vary from 20°C to 90°C, with values in the range 40°C to 90°C being preferred.
The exact PAG used may depend on the cloud point required, which in turn depends on
the intended final application of the concentrate.
[0039] Amounts of component (B3) range from 5 to 15wt%, preferably from 6 to 14wt% and more
preferably from 7 to 13wt%.
Component (B4)
[0040] Component (B4) is water, and is present in an amount of 60-80wt%, preferably 69-78wt%,
more preferably 70-77wt%. Alternative prefered ranges are 60-72wt%, preferably 62-70wt%.
[0041] Each of the above components of the concentrate (A1)-(A3) and (B 1)-(B3) may comprise
either a single compound or more than one compound.
[0042] A preferred metalworking fluid concentrate formulation comprises
(A1) 1.5 - 3.7wt% of a blend of a C12-C24, preferably a C14-C20 alcohol with a fatty acid ester R1CO2R2 where R1 is a C12-C24, preferably C14-C20 hydrocarbyl acid residue and R2 is a C1-C8 alcohol residue, preferably a residue of methanol, 2-ethylhexanol, ethanol, butanol
or isotridecanol;
(A2) 1.5 - 3.7wt% wt% of a surfactant which is either
- (i) nonionic, being a hydrophobic C10-C28 portion optionally modified with 1-20 units of a hydrophobic polyalkoxylate chain
or alternatively a C10-C28 fatty acid esterified with a polyfunctional alcohol, or
- (ii) anionic, being a hydrophobic C10-C28 portion optionally modified with 1-20 units of a hydrophobic polyalkoxylate chain
and capped with an anionic group;
(A3) 0.5 - 3.0wt% of additives selected from anti-gelling agents, foam control agents,
anti-wear additives, extreme pressure additives, pH buffers and biocides;
(B1) 6 - 15wt% of an amine which is water-soluble at room temperature selected from
aminomethylpropanol (AMP-95), 3-amino-4-octanol, diglycolamine (DGA), monoethanolamine
(MEA), monoisopropanolamine (MIPA), butylethanolamine (NBEA), dicylclohexylamine (DCHA),
diethanolamine (DEA), butyldiethanolamine (NBDEA), triethanolamine (TEA), and methylpentamethylenediamine;
(B2) 2 - 5wt% of a water-soluble corrosion inhibitor;
(B3) 5 - 15wt% of a polyalkylene glycols (PAG) having an ethylene oxide content of
20-75% and a cloud point between 20°C and 90°C;
(B4) 60 - 80wt% of water.
[0043] Formulations which are particularly suited for metalworking operations at relatively
high temperatures, such as those involving ferrous metals, preferably contain amounts
of the various components listed above as follows:
(A1) 1.8 to 3.7wt%, preferably from 2 to 3wt%, more preferably from 2.6 to 3.0wt%;
(A2) 1.8 to 3.7wt%, preferably from 2 to 3wt%, more preferably from 2.6 to 3.0wt%;
(A3) 0.6 to 1.5wt%, preferably from 0.7 to 1.4wt%, more preferably from 0.7 to 1.0wt%;
(B1) 6.5 to 10wt%, preferably from 7 to 8wt%;
(B2) 2.1 to 2.9wt%, preferably from 2.2 to 2.8wt%, more preferably from 2.3 to 2.6wt%;
(B3) 6 to 14wt%, preferably from 7 to 13wt%, more preferably from 8 to 10wt%;
(B4) 69-78wt%, preferably 70-77wt, more preferably from 72 to 76wt%.
[0044] A particularly preferred formulation suited for metalworking operations at relatively
high temperatures is a metalworking fluid concentrate comprising
(A1) 2.6 to 3.0wt% of a mixture of G16 guerbet alcohol and methyl oleate/methyl palmitate;
(A2) 2.6 to 3.0wt% of a mixture of oleth-9-carboxyate and either a C16-C18 phosphate ester or oxirane, 2-methyl, polymer with oxirane, hexadecyl ether (CAS
9087-53-0);
(A3) 0.7 to 1.0wt% of additives selected from anti-gelling agents, foam control agents,
anti-wear additives, extreme pressure additives, pH buffers and biocides;
(B1) 7 to 8wt% of triethanolamine;
(B2) 2.3 to 2.6wt% of a polycarboxylic acid;
(B3) 8 to 10wt% of a polyalkylene glycol (PAG) having an ethylene oxide content of
40-75% and a cloud point of 60-85°C;
(B4) 72 to 76wt% water.
[0045] Formulations which are particularly suited for metalworking operations at lower temperatures,
such as those involving non-ferrous ("yellow") metals or wire drawing operations,
typically contain lower amounts of water, because the lower operating temperature
means that the PAG reaches its cloud point more slowly and hence additional lubricant
components are required. If the worked metal is copper, such as in some wire drawing,
such formulations also require higher amounts of corrosion inhibitors due to the presence
of corrosive copper ions. Preferred formulations for such operations contain amounts
of the various components listed above as follows:
(A1) 1.8 to 3.7wt%, preferably from 2.5 to 3.7wt%, more preferably from 3.5 to 3.7wt%;
(A2) 1.8 to 3.7wt%, preferably from 2.5 to 3.7wt%, more preferably from 3.5 to 3.7wt%;
(A3) 1.5 to 3.0wt%, preferably from 1.8 to 2.6wt%, more preferably from 2.0 to 2.4wt%;
(B1) 8 to 15wt%, preferably from 9 to 14wt%, more preferably from 10 to 12wt%;
(B2) 22.1 to 4.5wt%, preferably from either 2.2 to 2.8wt% or 4.0 to 4.5wt%; more preferably
from 2.3 to 2.6wt% or 4.0 to 4.5wt%, with the higher range preferred for use with
copper;
(B3) 6 to 14wt%, preferably from 7 to 13wt%, more preferably from 8 to 10wt%;
(B4) 60-72wt%, preferably 62-70wt%, more preferably from 63 to 68wt%.
[0046] A particularly preferred formulation for lower temperature operation is a metalworking
fluid concentrate comprising
(A1) 3.5 to 3.7wt% of a mixture of G16 guerbet alcohol and methyl oleate/methyl palmitate;
(A2) 3.5 to 3.7wt% of a mixture of oleth-9-carboxyate and either a C16-C18 phosphate ester or oxirane, 2-methyl, polymer with oxirane, hexadecyl ether (CAS
9087-53-0);
(A3) 2.0 to 2.4wt% of additives selected from anti-gelling agents, foam control agents,
anti-wear additives, extreme pressure additives, pH buffers and biocides;
(B1) 10-12wt% of triethanolamine;
(B2) 2.3 to 2.6wt% or 4.0 to 4.5wt%of a polycarboxylic acid and/or benzotriazole;
(B3) 8 to 10wt% of a polyalkylene glycol (PAG) having an ethylene oxide content of
40-75% and a cloud point of 40-60°C;
(B4) 63 to 68wt% water.
[0047] The metalworking fluid concentrate is preferably formulated by mixing components
(A1)-(A3) and (B1-B4) as two separate formulations or phases (A) and (B), which are
then combined to form the final formulation. For example components (B1) and (B2)
may be dissolved in water (B4), and the PAG (B3) dissolved in the resulting solution.
Pre-blended components (A1)-(A3) may then be added. Components (A1)-(A3) may be regarded
as oleaginous components, and (B1)-(B4) as aqueous components similar to a fully synthetic
metalworking fluid.
[0048] A key feature of the present invention is that the oleaginous phase (A) and the aqueous
phase (B) are capable of forming a stable emulsion when mixed together. The precise
amounts of component (A2) can be adjusted in order to optimise the long-term stability.
[0049] For use the metalworking fluid concentrate is diluted with water in a known manner,
either prior to or during use. Accordingly a further aspect of the invention provides
a metalworking fluid comprising 3-20wt% of the above metalworking fluid concentrate
and 80-97wt% of water. Preferably the concentrate comprises 10-15wt% of the metalworking
fluid.
[0050] The present invention will now be described by way of example only, with reference
to illustrative embodiments.
EXAMPLE 1
[0051] A drawing oil concentrate was formulated by forming an oleaginous phase (A) comprising
components (A1)-(A3) and an aqueous phase (B) comprising components (B1)-(B4). The
two phases were then mixed together to form an emulsion having the composition shown
in Table 1:
TABLE 1
| Component |
Compound |
wt% |
| A1 |
G16 Guerbet alcohol |
1.8 |
| A1 |
CE-1875 (methyl oleate/methyl palmitate) |
0.9 |
| A2 |
Oleth-9-carboxyate |
0.9 |
| A2 |
Oxirane, 2-methyl, polymer with oxirane, hexadecyl ether (CAS 9087-53-0) |
1.8 |
| A3 |
Foamban® 1840 |
0.1 |
| A3 |
Ethyl diglycol ether |
0.75 |
| B1 |
Triethanolamine 90% |
14.44 |
| B2 |
Polycarboxylic acid 50% |
4.0 |
| B2 |
Benzotriazole |
0.4 |
| B3 |
PAG W270 (75% EO, cloud point 85°C) |
9.0 |
| B4 |
Water |
65.91 |
[0052] To evaluate its stability, the emulsion was diluted in both deionized water and also
water containing 500ppm Ca salts to a concentration of 10%. In both cases the result
was a bright, semi-translucent and stable emulsion.
[0053] The performance of this formulation was compared with two commercially available
non-ferrous wire drawing oils, one a soluble drawing oil and the other a fully synthetic
drawing oil, using a Reichert wear tester, which determines overall lubrication by
measuring the weight loss of the bearing pin, and also determines the time taken to
establish a lubricating film by measuring the time taken for noise drop off. All formulations
were used as a 10% dilution in water. The results are shown in Table 2 below:
TABLE 2
| |
Noise drop-off time (secs) |
% weight loss of bearing pin |
| Example 1 |
17.5 |
14.9 |
| Commercial soluble drawing oil |
78.5 |
53.4 |
| Commercial fully synthetic drawing oil |
21.5 |
26.5 |
[0054] It can be seen that Example 1 provides lubrication slightly more rapidly than the
fully synthetic oil, and much more rapidly than a soluble oil. Overall lubrication
was also significantly better than both commercial oils.
EXAMPLE 2
[0055] Example 2 is a general purpose metal-cutting fluid designed for use with both ferrous
and non-ferrous metals. It was formulated in the same way as Example 1, and has the
composition shown in Table 3:
TABLE 3
| Component |
Compound |
wt% |
| A1 |
G16 Guerbet alcohol |
1.8 |
| A1 |
CE-1875 (methyl oleate/methyl palmitate) |
0.9 |
| A2 |
Oleth-9-carboxyate |
0.1 |
| A2 |
C16-C18 phosphate ester |
2.7 |
| A3 |
Foamban® 1840 |
0.3 |
| A3 |
20% bisisothiazolinone in glycol (biocide) |
1.2 |
| A3 |
Ethyl diglycol ether |
0.75 |
| B1 |
Triethanolamine 90% |
7.8 |
| B2 |
Polycarboxylic acid 50% |
2.5 |
| B3 |
Pluronic PE6400 (PO/EO block, -40% PEG) |
9.0 |
| B4 |
Water |
72.95 |
[0056] The stability of this formulation was found to be similar to that of Example 1. The
performance of this formulation was compared with two commercially available metalworking
fluid concentrates, one a soluble oil and the other a semi-synthetic cutting fluid,
using a Reichert wear tester as in Example 1. All formulations were used as a 10%
dilution in water. The results are shown in Table 4 below:
TABLE 4
| |
Noise drop-off time (secs) |
% weight loss of bearing pin |
| Example 2 |
21.5 |
14.9 |
| Commercial soluble cutting oil |
100 |
81.7 |
| Commercial semi-synthetic cutting oil |
100 |
77.4 |
[0057] It can be seen that Example 2 provides lubrication much more rapidly than both commercial
oils, and overall lubrication was also significantly better than both commercial oils.
EXAMPLE 3
[0058] Example 3 is a metal-cutting fluid designed for use with non-ferrous metals, which
are typically softer and therefore generate less heat. As a result the temperature
of the working surface rises to the cloud point of component B3 more slowly, thereby
requiring a higher degree of lubrication from the oleaginous phase. Consequently the
amount of oleaginous phase is higher and the amount of water lower in this Example.
Such formulations may also require a higher level of corrosion inhibitor due to the
presence of corrosive copper ions from the worked metal. Example 3 was formulated
in the same way as Example 1, and has the composition shown in Table 5:
TABLE 5
| Component |
Compound |
wt% |
| A1 |
G16 Guerbet alcohol |
2.42 |
| A1 |
CE-1875 (methyl oleate/methyl palmitate) |
1.21 |
| A2 |
Oleth-9-carboxyate |
1.21 |
| A2 |
Oxirane, 2-methyl, polymer with oxirane, hexadecyl ether (CAS 9087-53-0) |
2.42 |
| A3 |
Foamban® 1840 |
0.13 |
| A3 |
20% bisisothiazolinone in glycol (biocide) |
1.2 |
| A3 |
Ethyl diglycol ether |
1.01 |
| B1 |
Triethanolamine 90% |
11.9 |
| B2 |
Citric acid monohydrate |
0.5 |
| B2 |
Polycarboxylic acid 50% |
2.5 |
| B3 |
Pluronic RPE1740 (EO/PO block. -40% PEG) |
9.0 |
| B4 |
Water |
66.5 |
[0059] The stability of this formulation was found to be similar to that of Example 1. The
performance of this formulation was compared with two commercially available metalworking
fluid concentrates, one a non-ferrous cutting fluid and the other a semi-synthetic
cutting fluid, using a Reichert wear tester as in Example 1. All formulations were
used as a 10% dilution in water. The results are shown in Table 6 below:
TABLE 6
| |
Noise drop-off time (secs) |
% weight loss of bearing pin |
| Example 3 |
11 |
9.0 |
| Commercial soluble cutting fluid |
100 |
98.3 |
| Commercial semi-synthetic cutting fluid |
100 |
77.4 |
[0060] It can be seen that Example 3 provides lubrication much more rapidly than both commercial
oils, and overall lubrication was also significantly better than both commercial oils.
1. A metalworking fluid concentrate comprising
(A1) 1.5 - 4.0wt% of a blend of a C8-C30 alcohol with a fatty acid ester R1CO2R2 where R1 is a C8-C30 acid residue and R2 is a C1-C12 alcohol residue;
(A2) 1.5 - 4.0wt% wt% of a surfactant;
(A3) 0.5 - 3.0wt% of additives selected from anti-gelling agents, foam control agents,
anti-wear additives, extreme pressure additives, pH buffers and biocides;
(B1) 6 - 15wt% of an amine which is water-soluble at room temperature;
(B2) 2 - 5wt% of a corrosion inhibitor which is water-soluble at room temperature;
(B3) 5 - 15wt% of a compound selected from ethylene oxide or propylene oxide block
copolymers, ethylene oxide or propylene oxide random copolymers, ethylene oxide or
propylene oxide polymer esters and ethylene oxide ethers; and
(B4) 60-80wt% of water.
2. Metalworking fluid concentrate according to claim 1, comprising
(A1) 1.5 - 3.7wt% of a blend of a C12-C24, preferably a C14-C20 alcohol with a fatty acid ester R1CO2R2 where R1 is a C12-C24, preferably C14-C20 hydrocarbyl acid residue and R2 is a C1-C8 alcohol residue, preferably a residue of methanol, 2-ethylhexanol, ethanol, butanol
or isotridecanol;
(A2) 1.5 - 3.7wt% wt% of a surfactant which is either
(iii) nonionic, being a hydrophobic C10-C28 portion optionally modified with 1-20 units of a hydrophobic polyalkoxylate chain
or alternatively a C10-C28 fatty acid esterified with a polyfunctional alcohol, or
(iv) anionic, being a hydrophobic C10-C28 portion optionally modified with 1-20 units of a hydrophobic polyalkoxylate chain
and capped with an anionic group;
(A3) 0.5 - 3.0wt% of additives selected from anti-gelling agents, foam control agents,
anti-wear additives, extreme pressure additives, pH buffers and biocides;
(B1) 6 - 15wt% of an amine which is water-soluble at room temperature selected from
aminomethylpropanol (AMP-95), 3-amino-4-octanol, diglycolamine (DGA), monoethanolamine
(MEA), monoisopropanolamine (MIPA), butylethanolamine (NBEA), dicylclohexylamine (DCHA),
diethanolamine (DEA), butyldiethanolamine (NBDEA), triethanolamine (TEA), and methylpentamethylenediamine;
(B2) 2 - 5wt% of a water-soluble corrosion inhibitor;
(B3) 5 - 15wt% of a polyalkylene glycols (PAG) having an ethylene oxide content of
20-75% and a cloud point between 20°C and 90°C;
(B4) 60 - 80wt% of water.
3. Metalworking fluid concentrate according to claim 2 wherein component (A1) comprises
guerbet alcohol plus methyl oleate and/or methyl palmitate.
4. Metalworking fluid concentrate according to any preceding claim wherein component
(A2) is selected from fatty alcohol alkoxylates, polyethylene glycol esters, sorbitan
esters, sorbitan ester alkoxylates, alkyl ether carboxylates, sulfosuccinates, sulphonates,
alkyl phosphate esters and alkyl ether phosphate esters.
5. Metalworking fluid concentrate according to any preceding claim wherein for component
(A3),
any anti-gel agents present comprise glycols or glycol ethers;
any biocides present comprise formaldehyde releasing agents, hexahydratriazine or
derivatives, methylene bis morpholene, oxazoladine or derivatives, isothiazolinones
or derivatives or iodo propyl butyl carbamate-fungicide;
any extreme pressure additives present comprise chlorinated and sulfurized fatty acids
or esters, polysulfides, organophosphates, or neutralized phosphate esters;
any foam control agents present comprise methyl silicone oil, fluorosilicone oil or
polyacrylate.
6. Metalworking fluid concentrate according to any preceding claim wherein component
(B1) is triethanolamine (TEA).
7. Metalworking fluid concentrate according to any preceding claim wherein component
(B2) is selected from alkylphosphonic acids, alkali and alkanolamine salts of carboxylic
acids, undecandioic/dodecandioic acid and its salts, C4-C22 carboxylic acids and their salts, tolytriazole and its salts, benzotriazole and its
salts, imidazoline and its salts, alkanolamines and amides, sulfonates, alkali and
alkanolamine salts of naphthenic acids, phosphate ester amine salts, alkali nitrites,
alkali carbonates, carboxylic acid derivatives, alkylsulfonamide carboxylic acids,
arylsulfonamide carboxylic acids, fatty sarkosides, phenoxy derivatives and sodium
molybdate.
8. Metalworking fluid concentrate according to any preceding claim wherein component
(B3) is a polyalkylene glycol (PAG) having an ethylene oxide content of 20-75% and
a cloud point between 40°C and 75°C.
9. Metalworking fluid concentrate according to any preceding claim, wherein the components
are present in amounts:
(A1) 1.8 to 3.7wt%, preferably from 2 to 3wt%;
(A2) 1.8 to 3.7wt%, preferably from 2 to 3wt%;
(A3) 0.6 to 1.5wt%, preferably from 0.7 to 1.4wt%;
(B1) 6.5 to 10wt%, preferably from 7 to 8wt%;
(B2) 2.1 to 2.9wt%, preferably from 2.2 to 2.8wt%;
(B3) 6 to 14wt%, preferably from 7 to 13wt%;
(B4) 69-78wt%, preferably 70-77wt%.
10. Metalworking fluid concentrate according to claim 9, wherein the components are present
in amounts:
(A1) 2.6 to 3.0wt%;
(A2) 2.6 to 3.0wt%;
(A3) 0.7 to 1.0wt%;
(B1) 7 to 8wt%;
(B2) 2.3 to 2.6wt%;
(B3) 8 to 10wt%;
(B4) 72-76wt%.
11. Metalworking fluid concentrate according to claim 10, wherein the components are:
(A1) a mixture of G16 guerbet alcohol and methyl oleate/methyl palmitate;
(A2) a mixture of oleth-9-carboxyate and either a C16-C18 phosphate ester or oxirane, 2-methyl, polymer with oxirane, hexadecyl ether (CAS
9087-53-0);
(A3) additives selected from anti-gelling agents, foam control agents, anti-wear additives,
extreme pressure additives, pH buffers and biocides;
(B1) triethanolamine;
(B2) a polycarboxylic acid;
(B3) a polyalkylene glycol (PAG) having an ethylene oxide content of 40-75% and a
cloud point of 60-85°C;
(B4) water.
12. Metalworking fluid concentrate according to any of claims 1 to 8, wherein the components
are present in amounts:
(A1) 1.8 to 3.7wt%, preferably from 2.5 to 3.7wt%;
(A2) 1.8 to 3.7wt%, preferably from 2.5 to 3.7wt%;
(A3) 1.5 to 3.0wt%, preferably from 1.8 to 2.6wt%;
(B1) 8 to 15wt%, preferably from 9 to 12wt%;
(B2) 2.1 to 4.5wt%, preferably from either 2.2 to 2.8wt% or 4.0 to 4.5wt%;
(B3) 6 to 14wt%, preferably from 7 to 13wt%;
(B4) 60-72wt%, preferably 62-70wt%.
13. Metalworking fluid concentrate according to claim 12, wherein the components are present
in amounts:
(A1) 3.5 to 3.7wt%;
(A2) 3.5 to 3.7wt%;
(A3) 2.0 to 2.4wt%;
(B1) 10 to 12wt%;
(B2) 2.3 to 2.6wt% or 4.0 to 4.5wt%;
(B3) 8 to 10wt%;
(B4) 63 to 68wt%.
14. Metalworking fluid concentrate according to claim 13, wherein the components are:
(A1) a mixture of G16 guerbet alcohol and methyl oleate/methyl palmitate;
(A2) a mixture of oleth-9-carboxyate and either a C16-C18 phosphate ester or oxirane, 2-methyl, polymer with oxirane, hexadecyl ether (CAS
9087-53-0);
(A3) additives selected from anti-gelling agents, foam control agents, anti-wear additives,
extreme pressure additives, pH buffers and biocides;
(B1) triethanolamine;
(B2) a polycarboxylic acid and/or benzotriazole;
(B3) a polyalkylene glycol (PAG) having an ethylene oxide content of 40-75% and a
cloud point of 40-60°C;
(B4) water.
15. Metalworking fluid comprising 3-20wt%, preferably 10-15wt%, of a metalworking fluid
concentrate as defined in any preceding claim and 80-97wt% of water.