Patent Application
20220251465
The present application relates to lubricating oil compositions. In particular, the present application pertains to a once through application of a non-drip lubricating oil compositions for roller chains and driving power trains having complex chain linkages.
Lubricants typically comprise base oil(s) with additives. Such lubricating oils have been in use for lubrication of roller chains and driving power trains.
Simple tacky heavy viscous lubricants made of animal waxes, petroleum base stocks have been used since historical days. These viscous chain lubricants provide great film strength to ensure metal to metal contact does not occur, and hence have high load bearing characteristics.
The roller chains have rollers in each chain link, rotating on pins. The rollers and pins are held in place by means of end plates, more specifically inner and outer end plates. There are different types of motions encountered in these chains which demand the following additional properties from a lubricant:
CN103773574 patent application relates to lubrication oil and a preparation method thereof. Disclosed lubricating oil composition comprises percentage by weight: 1.6 to 12.0% of composite additive package; 0.0001 to 0.01% of anti-foaming agent; and 70 to 90% of oil-soluble polyalkylene glycol; and, the balance base oil.
EP0468109 patent application provides biodegradable lubricants and functional fluids for use in an operation of lubricating oil. The oil comprises at least 10% by volume of at least one substantially biodegradable liquid hydrocarbon.
WO2016/043800 patent publication relates to a lubricant composition comprising a lubricant base, an oil soluble polyalkylene glycol, and an additive comprising (1) alkylated phenyl-α-naphthylamine; and (2) 2,2,4-trialkyl-1,2-dihydroquinoline.
In an aspect, the present application provides a lubricating oil composition comprising a) an oil soluble polyalkylene glycol polymer; b) a vegetable base stock; and c) an organic solvent excluding alcohol. The oil soluble polyalkylene glycol and the vegetable base stock are present in the weight ratio from 1:2.6 to 1:8.
The biodegradable lubricating oil composition has high film strength, high load carrying capability, zero drip property and maximum penetrability in the chain linkages, for roller chains and driving power trains having complex chain linkages.
The above summary is not intended to describe each embodiment or every implementation of the finding disclosed here. The Figures, Detailed description and Examples that follow more particularly exemplify these embodiments.
The disclosure herein may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings, in which:
The roller chains, which are increasingly present in two and three-wheeler motorcycles and driven by a gasoline power train, have the following specific demands.
The lubrication of these complex linkages is often not accessible or visible from the outer surface of the chain and has always been a challenge.
The use of low viscosity chain spray lubricants has been increasingly prevalent on light loaded chains such as for motorcycles and bicycles where stickiness from high viscous tacky products on the chain surface can seriously reduce the useful life of the chains due to the Three Body abrasion phenomenon. However, these chain lubricants often suffer low film strength and low load carrying capabilities. Moreover, viscous products cannot be sprayed owing to the limitations of being dispersible by gaseous propellants.
Some products exist where the viscous lubricants are thinned down by using fast evaporating solvents and then sprayed from canisters and aerosols. This has a bigger disadvantage of suffering from excessive dripping which results in wastage of the useful lubricant. Further, the application areas do not receive as much lubricant as required, as the sprayed product does not have enough time to sink in on the surface of the chain, and instead flows down and away due to the dripping action of the solvent.
Heavy and tacky lubricants have a limit for penetrating intricate gaps present in modern day roller chain construction. In addition to suffering from poor penetration and wetting of internal linkages, these lubricants remain on the outer surface of the chain allowing the chain to attract a lot of dirt and thereby making the chain sticky. This further has a damaging effect when the chains are exposed to dust particles and minerals found in the dust laden roads and other challenging environments.
Despite new types of material and advanced technology, the complex chain linkages still require effective lubrication to meet all the demands of the roller chains and gasoline driven power trains. Therefore, there is a need for lubricating oil compositions which provide effective chain lubrication, reduced wear on chain links, impact damping, high film strength, high load carrying capability, dispersible into fine mist, reduced galling, and zero drip characteristics, which thereby enables maximum residence time for the lubricant on the metal topography allowing better lubrication of individual elements in the chain linkages.
For the purposes of the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any of the operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification are to be understood as being modified in all instances by the term “about”. It is noted that, unless otherwise stated, all percentages given in this specification and appended claims refer to percentages by weight of the total composition.
Thus, before describing the present invention in detail, it is to be understood that this invention is not limited to particularly exemplified systems or method parameters that may of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only, and is not intended to limit the scope of the invention in any manner.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In the case of conflict, the present document, including definitions will control.
It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to a “polymer” may include two or more such polymers.
The term “ free” as used in the specification means that the composition is completely free of the referred agents or additives.
The term “tribological additives” as used in the specification means additives that have been added to the composition which are surface acting and sacrificial in nature, protecting the parent surface from effects of friction and consequent seizure and wear.
The term “tackifiers” refer to additives mixed in lubricants and greases to provide tack and surface adherence in fluid lubricants and stringiness in grease formulations. These are polymers like poly-isobutylenes, poly-alpha olefins or olefin copolymers and are miscible with the oil phase of the lubricant.
As used herein, the terms “comprising” “including,” “having,” “containing,” “involving,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to.
The recitation of all numerical ranges by endpoints is meant to include the endpoints of the range, all numbers subsumed within the range, and any range within the stated range.
In one aspect, the present application provides a lubricating oil composition for roller chains, increasingly present in two and three-wheeler motorcycles which are driven by a gasoline power train. The lubricating oil composition comprises a) an oil soluble polyalkylene glycol polymer; b) a vegetable base stock; and c) organic solvent excluding alcohol. The oil soluble polyalkylene glycol and the vegetable base stock are present in the weight ratio from 1:2.6 to 1:8.
The oil soluble polyalkylene glycol polymer may be derived from polymerization of butylene oxide monomers. In some embodiments, the oil soluble polyalkylene glycol polymer may be at least 12%, at least 14% or even at least 15% by weight of the lubricating oil composition and/or the oil soluble polyalkylene glycol polymer may be no greater than 24%, no greater than 21% or even no greater than 18% by weight of the lubricating oil composition. In accordance with an embodiment, the oil soluble polyalkylene glycol polymer is present from 15% to 18% by weight of the composition. Use of oil soluble polyalkylene glycol polymer in the said weight percentage range provides high film strength and metal affinity to the lubricant increasing the load carrying and durability characteristics for roller chains.
In accordance with an embodiment, the oil soluble polyalkylene glycol polymer has a kinematic viscosity from 612 cSt to 748 cSt at a temperature of 40° C. and a viscosity index of 170 or above. In some embodiments, the oil soluble polyalkylene glycol polymer viscosity may be at least 414 cSt, at least 500 cSt or even at least 612 cSt. The oil soluble polyalkylene glycol polymer when present in the said viscosity increases the load carrying capability and aids the anti-drip characteristics of the lubricant oil to a desired level set for its application.
In a specific embodiment, the oil soluble polyalkylene glycol polymer is obtained from the polymerisation of butylene oxide monomer group.
The lubricating oil composition in accordance with the disclosure comprises vegetable base stock as the base oil. In accordance with one embodiment, the vegetable base stock is present from 71% to 75% by weight of the composition. In some embodiments, the vegetable base stock may be at least 60%, at least 65% or even at least 71% by weight of the lubricating oil composition and/or the vegetable base stock may be no greater than 80%, no greater than 78% or even no greater than 75% by weight of the lubricating oil composition.
In one embodiment, the vegetable base stock includes, but is not limited to, castor oil, olive oil, peanut oil, rapeseed oil, corn oil, sesame oil, cotton seed oil, soybean oil, sunflower oil, hemp oil, linseed oil, tung oil, jojoba oil, lard oil, and/or derivatives thereof. In certain embodiments, the vegetable base stock includes double refined rapeseed oil, hydrogenated castor oil, and/or derivatives thereof. In a particular embodiment, the vegetable base stock is hydrogenated castor oil.
In accordance with an embodiment the vegetable base stock has a kinematic viscosity from 200 cSt to 300 cSt at a temperature of 40° C.
The oil soluble alkylene glycol and the vegetable base stock are present in a weight ratio from 1:2.6 to 1:8.
In some embodiments, the weight ratio of the oil soluble alkylene glycol and the vegetable base stock may be at least 1:2.6, at least 1:3, at least 1:3.5 or even at least 1:3.88 and/or the weight ratio may be no greater than 1:6.3, no greater than 1:5.5, no greater than 1:5 or even no greater than 1:3.88. In accordance with one embodiment, the oil soluble alkylene glycol and the vegetable base stock are present in the weight ratio from 1:3.88.
Synergistic effect is observed when one part of oil soluble polyalkylene glycol polymer is mixed with between 3 to 8 times by weight of the vegetable base stock which is dispersible in the presence of a solvent using a gaseous propellant to provide unique non-drip characteristics. The disclosed composition further satisfies the requirements of zero drip, disperseability, chain wear and elongation test requirements without the use of any flow modifier or thixotropic agents in the lubricant oil composition. This is due to the unique rheology and lower viscosity at room temperature allowing for non-drip feature and easy disperseability of the lubricant oil through an aerosol.
The lubricating oil composition further comprises a solvent. In accordance with one embodiment, the solvent is an organic solvent. In accordance with some embodiments, the solvent is selected from the group of organic solvents having an evaporation rate in the range of 6 to 9. The evaporation range here is a ratio of evaporation rate compared to reference n-butyl acetate. In accordance with some embodiments, the organic solvents include saturated hydrocarbons, oxygenated solvents, petroleum oils, aromatic hydrocarbons, ketones, glycols, glycol ethers, and/or halogenated solvents, excluding any alcohols.
In certain embodiments, the organic solvent is a non-polar hydrocarbon solvent. In some embodiments, the non-polar hydrocarbon solvent may be at least 4.5%, at least 5% or even at least 5.5% by weight of the lubricating oil composition and/or the non-polar hydrocarbon solvent may be no greater than 7%, no greater than 6.5% or even no greater than 6% by weight of the lubricating oil composition. In a particular embodiment, the non-polar hydrocarbon solvent is present up to 6% or up to 5% by weight of the composition. In one embodiment the non-polar hydrocarbon solvent is present at 5.5% by weight of the composition. The non-polar hydrocarbon solvent in accordance with the present disclosure may have a minimum purity of 99%. The solvent, e.g. the non-polar hydrocarbon solvent, of the present disclosure may be a fast evaporating solvent. In some embodiments, the evaporation rate (evaporation range here is a ratio of evaporation rate compared to reference n-butyl acetate) is from 6 to 9.
Addition of higher quantities of the solvent readily increases the penetration performance of the lubricant oil, which also helps in temporary reduction in viscosity to aid the lubricant in entering the crevices and minor clearances thus helping to protect the roller chain linkages.
In accordance with an embodiment, the lubricating oil composition further comprises tackifiers and additives. In a further embodiment, the additives may be tribological additives, anticorrosion additives and/or de-foaming agents, color pigments and/or perfumes.
In an embodiment the tackifiers is selected from the group consisting of but not limited to poly isobutylene, olefin copolymer and/or poly alpha olefins. In a certain embodiment the tackifier is long chain polyisobutylene having a kinematic viscosity of 2500 to 3300 cSt at 100° C. In some embodiments, the tackifier may be present in the lubricating oil composition in an amount no greater than 3.5% by weight, no greater than 3% by weight, no greater than 2% by weight or even no greater than 1.3% by weight. The tackifier in accordance with the present disclosure is present in the amount up to 1.3% by weight. The tackifiers present in such an amount increases the adhesion of oil on the metal substrate of the chain linkage.
The tribological additives, like extreme pressure additive and anti-wear additives, are used for improving the wear and seizure performance of the roller chains. The anti-wear additives include phosphorous, sulfur-phosphorous or chlorosulfur compounds, a chlorinated hydrocarbon compound or mixtures thereof. Examples of anti-wear additives include tri-cresyl phosphates, zinc dialkyl dithio phosphates and zinc dialkyl dithio carbamates. In some embodiments, the anti-wear additives may be present in the lubricating oil composition in an amount no greater than 5% by weight, no greater than 3% by weight, no greater than 2% by weight, or even no greater than 1% by weight. In some embodiments, the anti-wear additive in accordance with the present disclosure is present in the amount up to 1.6% by weight.
Extreme pressure additives include chlorine compounds like chlorinated paraffins, sulfur phosphorous compounds, sulfurized olefins, sulfurized polyols and organo sulfur compounds. These additives chemically react with the surface upon localized high pressure conditions initiated by sliding surface contacts and form a protective sacrificial tribo-layer. In some embodiments, the extreme pressure additives may be present in the lubricating oil composition in an amount no greater than 5% by weight, no greater than 3% by weight, no greater than 2% by weight or even no greater than 1.0% by weight. In one embodiment, the extreme pressure additive in accordance with the present disclosure is present in the amount up to 2.3% by weight.
The lubricating oil composition may further comprise other additives including further additional oxidation inhibitors, dispersants, viscosity index modifiers, rust inhibitors, and/or pour point depressants.
In accordance with an embodiment, the lubricating oil composition further comprises a corrosion inhibitor and a metal deactivator. The lubricating oil composition is further free of anti-sag and flow modifier additives. It is economically disadvantageous to add such additives as it involves the use of high-speed dispersion test equipment for manufacture of lubricant oil.
In accordance with an embodiment, the lubricating oil composition has a viscosity index as measured using ASTM D 2270 standard from 150 to 180. The viscosity retention at increased temperatures is brought about by the high viscosity index of oil soluble polyalkylene glycol polymer allowing retention of the oil film at localized contact zones where high temperatures result, where conventional oils get thinned and squeezed out.
The lubricating oil composition according to the present disclosure is synergistically shear stable and sag resistant, thereby allowing it to stay on the surface of the chain rendering the roller chain linkages a uniform coating of lubricant. The disclosed composition achieved the right amount of penetration index and zero drip characteristics needed to meet the application requirement in the roller chains.
The disclosed lubricating oil composition not only achieves high film strength that promises high load carrying capability but also easily and effortlessly disperses into fine mist using gaseous propellants. The disclosed lubricating oil exhibits zero dripping property and an extreme high viscosity index and thus a low application viscosity at room temperature. The viscosity of the lubricating oil composition is retained at the Hertzian contact zone, often in micron sizes where localized high temperatures are encountered. The lubricating oil composition further exhibits superior penetration by reaching the complex individual elements in chain linkages, thereby providing better lubrication.
Embodiment 1 is a lubricating oil composition comprising a) an oil soluble polyalkylene glycol polymer, b) a vegetable base stock, and c) an organic solvent excluding alcohol, wherein the oil soluble polyalkylene glycol and the vegetable base stock are present in a weight ratio from 1:2.6 to 1:8.
Embodiment 2 is a lubricating oil composition of Embodiment 1, further comprising tackifiers and additives.
Embodiment 3 is a lubricating oil composition of Embodiment 1, wherein the oil soluble polyalkylene glycol polymer is present in the range of 10% to 18% by weight of the composition.
Embodiment 4 is a lubricating oil composition of Embodiment 1, wherein the vegetable base stock is present in the range of 71% to 79% by weight of the composition.
Embodiment 5 is a lubricating oil composition of Embodiment 1, wherein the organic solvent is a fast evaporating solvent with evaporation rate (evaporation range here is a ratio of evaporation rate compared to reference n-butyl acetate) in the range of 6 to 9.
Embodiment 6 is a lubricating oil composition of Embodiment 1, wherein the organic solvent is present in the range of 4% to 7% by weight of the composition.
Embodiment 7 is a lubricating oil composition of Embodiment 1, wherein the organic solvent comprises at least one of saturated hydrocarbons, oxygenated solvents, petroleum oils, aromatic hydrocarbons, ketones, glycols, glycol ethers, and halogenated solvents.
Embodiment 8 is a lubricating oil composition of Embodiment 1, wherein the vegetable base stock comprises at least one of castor oil, olive oil, peanut oil, rapeseed oil, corn oil, sesame oil, cotton seed oil, soybean oil, sunflower oil, hemp oil, linseed oil, tung oil, jojoba oil, lard oil, and derivatives thereof.
Embodiment 9 is a lubricating oil composition of Embodiment 1, wherein the vegetable base stock is a hydrogenated castor oil.
Embodiment 10 is a lubricating oil composition of Embodiment 1, further comprising at least one of an anti-wear additive, extreme pressure additive, a corrosion inhibitor and a metal deactivator.
Embodiment 11 is a lubricating oil composition of Embodiment 1, wherein the vegetable base stock has a kinematic viscosity in the range of 200 cSt to 300 cSt at a temperature of 40° C.
Embodiment 12 is a lubricating oil composition of Embodiment 1, wherein the oil soluble polyalkylene glycol polymer has a kinematic viscosity in the range of 612 cSt to 748 cSt at a temperature of 40° C.
Embodiment 13 is a lubricating oil composition of Embodiment 1, wherein the composition is free of anti-slag and/or flow modifier additives.
Embodiment 14 is a lubricating oil composition of Embodiment 1 having a viscosity index as per ASTM D 2270 between 150 and 180.
These examples are merely for illustrative purposes and are not meant to be limiting on the scope of the appended claims. All parts, percentages, ratios, and the like in the examples and the rest of the specification are by weight, unless noted otherwise.
The components shown in Tables 2 and 3 were blended to prepare lubricating oil compositions. The lubricating oil compositions prepared in Inventive Examples and Comparative Examples were analyzed and then these compositions were tested for performance as described further below under section Test Methods. All the results are shown in Tables 2 and 3.
The identity of the specific constituents of the lubricant oil composition of the present disclosure is listed in Table 1.
Test Methods
The following tests have been performed to qualify the overall performance of the chain lubricants, these tests are:
Product Performance tests—simulating the actual motorcycle field conditions where the product must demonstrate its capability to perform in the conditions that would typically lead to premature failure of the motorcycle chain
Product Application tests—defining the application requirements of the product while being applied on the chain.
Product Performance Test
Accelerated chain wear and elongation testing: This is a load bearing capability test; the load bearing capability was tested in a simulated bench test of an actual motorcycle roller chain which was held between the two sprockets on a laboratory bench tester, this was driven at 2950 RPM for 72 hours, the driven sprocket had free sliding movement on a horizontal axis and was held in horizontal tensile load of 150 kilograms. This load was transferred to the chain, and the chain was lubricated every 24 hours. The machine was stopped for 5 minutes at the end of every 24 hours to enable re-lubrication of the chain.
Before start of the test, the factory chain sprocket set was washed and cleaned thoroughly in solvents hexane, toluene and ethanol and dried in an oven at 50° C. for 10 hours and cooled. This was done to ensure that the factory filled lubricant was removed completely and that the chain was dry and fresh for use with the formulated chain lubricant.
The load capability of the lubricant was deemed as Pass or Fail. The lubricant Failed if:
Product Application Tests
The specific components of the lubricant oil composition used in comparative examples are listed in Table 2
The specific components of the lubricant oil composition used in further inventive examples are listed in Table 3
It is evident from the data contained in Table 2 and 3, that the lubricant oil composition according to the present application (Inventive examples 1-8) exhibits high load carrying capability, zero drip property, blend stability, maximum disperseability and penetrability in the chain linkages. The comparative examples in 1-7 using alcohols, synthetic derived polymer, castor oil, and aliphatic solvent below and beyond the claimed weight ratios do not pass the performance test for all the critical performance attributes required for complex chain linkages.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201941016732 | Apr 2019 | IN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2020/053869 | 4/23/2020 | WO |
