Finished Lubricants

Spotlight on Grease

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Spotlight on Grease

From industrial machinery to the modern motor vehicle, technologies are changing rapidly—as are expectations for improved performance and efficiencies. For grease manufacturers, the challenge is to constantly enhance and modify formulations to keep pace with these ever-changing demands and requirements.

For decades, the industry has relied on the National Lubricating Grease Institute’s GC-LB Certification Mark, an easily identifiable logo, to help end users ensure the right greases are used for the right applications. After all, using an unsuitable product could result in costly equipment failure, or at least reduced efficiency and effectiveness. 

Yet while greases have seen their fair share of change over the years, NLGI’s globally recognized mark has not. When it was created, for example, vehicles did not have such long warranties and greases did not need to operate in such a wide temperature range. Many manufacturers have actually exceeded the standards, the technology overtaking them.

Now, 30 years after their introduction, Chuck Coe, consultant with Grease Technology Solutions who also sits on the NLGI board of directors, says it is time the NLGI grease specifications were enhanced to meet today’s performance and market needs. 

The changes will be twofold. First, said Coe, the existing GC-LB performance classification is being “upgraded,”along with standards organization ASTM International, focused on revising and improving current test methods. 

Originally targeting the automotive sector, GC-LB has long been recognized by specifiers as an indicator of quality and performance for greases used on wheel bearings and chassis systems. 

These past few decades, grease producers have been able to meet certain criteria and register their products so they can bear the mark on their packaging. In September 2019, a total of 308 products had been licensed, proving that they comply with ASTM D4950, “Standard Classification and Specification for Automotive Service Greases.”

It was recognized that some of the tests had precision problems, so ASTM is currently working on overhauling several of the tests. Specifically, this includes addressing the precision of the current wheel bearing life test, as well as ironing out problems with the fretting wear test.

Grease manufacturers will soon see an entirely new grease standard in place, too.

NLGI is hashing out a new high-performance multiuse (HPM) grease specification, said Coe. This is being finalized and, despite the current coronavirus lockdown, it remains on track to launch in January 2021. 

The HPM standard is aimed at industrial applications and has been developed to cover everything from pumps to conveyor belts, rather than the automotive sector already served by GC-LB, he noted. 

The new grease certification mark will not replace the long-standing GC-LB standard but will run in parallel, setting out criteria for high-performance multiuse greases. NLGI has committed to continuing support of GC-LB certification and the use of the mark. 

“As users come to realize HPM is actually superior and it becomes more widely recognized, it wouldn’t surprise me if they eventually shifted across to this new specification, but we will not be ending our support for the GC-LB spec,” Coe assured.

Besides a base HPM specification, there will also be five sub-categories: Enhanced Water Resistance (WR), Enhanced Load Carrying Capacity (HL), Enhanced Salt Water Corrosion Resistance (CR), Enhanced Long Life (LL), and Enhanced Low Temperature (LT) greases.

NLGI expects to have HPM and four of these enhancements ready for the start of next year, but Coe said the fifth, the LL enhancement, will follow sometime later as it will take significantly longer—perhaps a few years—for NLGI and ASTM to develop and approve the necessary dynamic grease life test.

“This is just the start, and it will certainly evolve over time. We need to gather far more data for some of the testing so haven’t set the final limits yet,” he said. 

“Unlike GC-LB, I think it far more likely that the HPM spec will be updated periodically. We anticipate that this will be used as the foundation and that OEMs or end users will eventually put additional requirements on top of that.”

A working group held initial discussions about the new specification in 2015, with a steering committee formed in mid-2019. Industry stakeholders have been invited to offer their input and feedback about the new requirements. 

Despite the disruption caused by the Covid-19 outbreak, Coe remains confident everything will stay on schedule in the months ahead, with final approval expected by September. At the time of writing, the logo design was still to be confirmed.

A day-long online workshop held in March involved 45 participants including OEMs, grease producers, additive suppliers and test equipment manufacturers, to discuss progress and to build consensus—demonstrating widespread support from the industry. 

The proposals have been welcomed by the grease sector, he noted, and the reception has been overwhelmingly positive about the new HPM specification.

“It has been decades since the last industry approved certified spec was issued and there really is no better time than the present to introduce an improved one,” said Wayne Mackwood, global head of detergent and grease technology at Lanxess. “This will help level the playing field and make the decision-making process for the end user much simpler and more confident.”

“The time is right to have a specification aimed at industrial use—to have a foundation in place for high-performance greases with sub-categories targeting the needs of different applications within the industrial space,” added Matthew McGinnis, vice president, commercial development at Daubert Chemical Co. “I think it’s a great stepping stone to have something more applicable to real-world end users, and I’m really happy with the direction it’s going.”

“There’s a lot of colorful language in the lubricants industry around performance, which can set high expectations for products that maybe should be considered average,” he continued. “This makes it difficult for end users to correctly identify the grease that best suits their needs. The new certification mark should help diminish the confusion created by various marketing claims and help people understand whether these greases truly are worth a premium.”

David Turner, product specialist in the Fluid Technology Group at Citgo, agreed. “Many greases are used in a wide variety of applications today, and some grease manufacturers make claims for applications for which their greases may not actually be suitable,” he said. “The introduction of the NLGI HPM grease specification will set a standard for general use greases that can be quoted in equipment operations and maintenance manuals and requests for quotations for bid purposes. The NLGI HPM specification will provide a common basis upon which greases can be compared.”  

“Once these specifications are instituted, it will be difficult to imagine how the industry survived without them,” Turner concluded.

Today, companies that want to carry the GC-LB Certification Mark need to fill out forms, certify they have the relevant test data and submit the information and fees to NLGI. An audit program is also in place. The new standard will be far more rigorous, said Coe. With HPM, the audit procedure is going to be even more extensive, with a requirement to submit the supporting test data.

“I’m not familiar with anything like this being done anywhere else in the world,” insisted Coe. “This is a real landmark.”

For a rapidly changing marketplace that is becoming even more demanding of its greases, having suitable standards in place that meet these expectations is paramount. In the coming months, the various stakeholders will be focused on finalizing these plans to ensure a frictionless transition.  

Focused on Cost Savings and Performance

Continuous improvement and innovation are vital to ensuring today’s greases can meet demanding applications.

Dorf Ketal, a well-established supplier to the oil and gas industry, has a proven track record of manufacturing lubricant and grease additives to protect machinery, reduce wear, extend equipment life and help improve output and efficiencies. Since entering the lubricant additives business in 2007, Dorf Ketal has grown its portfolio and believes innovation is an important component in all its products. 

Among them is PX-3871, a multifunctional lubricity improver and dropping point additive for grease.  It outperforms competing products and offers significant cost savings. The unique alkyl borate ester improves a grease’s dropping point by 10% and boosts its load carrying capacity by 20-40%. This high-performance additive can reduce the cost of lithium greases by 3-13 cents/lb. This means that users could see their dropping point additive costs fall by as much as 50%.

Dorf Ketal also offers ashless dispersants, corrosion inhibitors and antioxidants for use in grease and other lubricant applications.   

To find out more about Dorf Ketal and its range of lubricant additives, visit https://www.dorfketal.com/industry-solutions/lubricant-additives-components

From Extreme-pressure Components to Fully Formulated Packages, LANXESS Offers Different Solutions for Grease Systems

From Extreme-pressure Components to Fully Formulated Packages, LANXESS Offers Different Solutions for Grease Systems

LANXESS’ long-standing experience with extreme-pressure additives has positioned it as a leading supplier of sulfur carriers. In the recent Spotlight on Metalworking, sulfur carriers were shown to embody a powerful and versatile solution for cutting oils, as well as for gear industrial oils. However, due to the release of free sulfur, these kinds of additives can have a detrimental effect on the corrosiveness of a grease system when the contact material is a yellow metal (i.e. copper alloys). The free sulfur reacts with the copper to create copper sulfides, leaving black discoloration on the metal surface.

So, what extreme-pressure alternatives are there that could be used in greases, and how can we achieve optimal performance without compromising with copper corrosion? 

Only a handful of solutions have been put forward over the years, such as the formulation of greases with balanced usage of active sulfur carriers and yellow metal inhibitors, the use of inactive sulfur carriers like sulfurized isobutenes (SIB), and specifying alkyl-dimercaptothiadiazoles or DMTD derivatives. 

DMTD derivatives have a primary function of providing yellow metal inhibitions by creating a protective layer that prevents the contact between free sulfur and the metal surface while also acting as a sulfur scavenging agent. (See Figure 1.) 

As a distinctive feature from other yellow metal inhibitors (such as benzotriazole, tolytriazoles and their derivatives), DMTD derivatives also provide extreme-pressure properties, as they have linked sulfur within their mercaptane and thiadiazole structures that can be activated when the pressure and temperature thresholds are met. This prevents cold welding of the contacting surfaces. 

LANXESS revolutionized the development of DMTD derivatives in the 1980s with the introduction of Additin® RC 8210. This has since become the popular choice of grease manufacturers because of its yellow metal inhibition, extreme-pressure properties, wear protection and lower odor.

By comparing the performance of Additin® RC 8210 to SIB (Figure 2), we can draw the following observations:

a) Extreme-pressure: Additin® RC 8210 and SIB provide significant weld load improvement over the grease with no additives at all. 

b) Wear protection: SIB had a negative effect on wear, whereas Additin® RC 8210 did not have any damaging impact on the grease.

c) Copper corrosion: Additin® RC 8210 and SIB inhibited or did not promote corrosion of the contacting metal.

d) Odor: Additin® RC 8210 had a lower odor compared with SIB.

Besides these four factors, the differences in thermal stability of these substances must also be considered. (See Figure 3.)

Data suggests that a DMTD derivative such as Additin® RC 8210 is the better option when considering the operational temperatures of the grease, if it ranges from 70-150°C.

Clearly, DMTD derivatives represent an outstanding extreme-pressure solution for grease systems where the contacting metal surfaces contain copper, cobalt or an alloy of these. 

Additive packages for greases

Grease manufacturers are looking for multipurpose additive packages suitable for a variety of base greases, offering well-balanced performance across different key properties such as anti-wear, corrosion inhibition and extreme pressure. To avoid changes that cost time and money, particularly for long-term applications, characteristics such as corrosion inhibition (including yellow metal inhibition) are of growing significance within the grease compositional make-up.

Suitable formulations need to consider antagonism and synergistic effects of the different components to provide well-balanced performance. LANXESS has a deep and long-term understanding of formulating well-balanced additive packages for grease application.

Grease packages from LANXESS are extremely versatile and provide grease formulators a wide range of options. Additive packages such as Additin® RC 9502 combine high extreme-pressure performance with good copper corrosion protection and low wear. (See Figure 4.) Furthermore, Additin® RC 9502 offers good thermal stability and low odor.

Over half the world´s multipurpose greases are still of the conventional lithium type due to its very versatile application range, despite the fact complex greases offer better thermal stability. Additin® RC 9502 enables very balanced performance and supports good corrosion resistance at EMCOR Rating compared with traditional grease packages that contain SIB (sulfurized isobutylene) as an EP additive. Additin® RC 9502 is not formulated with SIB but offers competitive EP performance in Four-ball tests, weld load (kgf) and wear scar (mm).

The remaining volume of base greases is highly diversified. Polyurea greases, in particular, have seen a renaissance due to e-mobility. Similar to the performance seen in lithium greases (Figure 5), Additin® RC 9502 also shows very positive performance in polyurea greases, outperforming traditional grease packages in the EMCOR Rating (Figure 6).

LANXESS is proud of the quality of its additives for grease systems and continues to innovate with its EP additives (sulfur carriers and DMTD derivatives) and grease packages, anti-wear additives, ferrous corrosion inhibitors and antioxidants.  o

For more information, visit https://lanxess.com/en/Company/Corporate-Structure/Business-Units/Lubricant-Additives-Business

Retraplex Diamond Blue is Drydene’s Crown Jewel

Drydene® is confident the latest addition to its popular Retraplex® line could become the grease of choice for the market.

Retraplex Diamond Blue™ is a new premium-grade lithium complex grease developed from the ground up that fills the market’s need for a truly versatile product—ideal for heavy-duty use whether in the commercial, agricultural, mining or construction sectors.

“There’s been a gap in the market for a product like this, and we believe we’ve created something really special,” says Dave Stover, product manager at Drydene Performance Products. “We’re always looking to expand our range, rework existing products and improve our chemistries. Product innovation is always a focal point for Drydene.”

Diamond Blue was launched in May after a year in development and extensive testing to ensure it could withstand the rigors of modern machinery.

Drydene wanted to develop a grease that not only excelled in reducing friction and extending the life of equipment but also boasted excellent wear protection, superior performance in wet conditions and a wide temperature range.

“The formula features some very robust extreme pressure properties, which also lends itself to heavy load bearing capacity,” he says. “The product’s water-resistant properties result in extremely low water washout and spray-off, which means the grease stays where it is supposed to be, and surfaces are always being protected. In addition, Diamond Blue has an extremely robust roll stability rating.”

“With our unique polymer configuration, the cohesion and adhesion of the grease helps provide a long-lasting protective boundary layer. It is very tenacious, and the lab and field testing we’ve done so far has been excellent in terms of physical consistency and extreme-pressure performance,” adds Stover.

Since Drydene introduced its Retraplex greases three years ago, it has quickly established itself as a trusted brand suited to a wide variety of applications. Diamond Blue joins Retraplex Onyx, Topaz, Ruby Red, and its top-selling Ruby Red Plus greases. 

“We know from our early market feedback there is tremendous excitement about the product, and I think the reaction is going to be very strong,” says Stover. “We’re pleased with the results and know our customers and users will be as well.”  

“Diamond Blue has unique physical characteristics and an advanced co-polymer configuration, which is what lends itself to how the product reacts to the elements in exposed environments. Where it shines the most is being outdoors in adverse conditions. It takes lithium complex grease to another level.” 

To find out more about Drydene Retraplex Diamond Blue, visit www.drydene.com/BLUEGREASE

Looking into the Long Term

Having specialized in the production of brine-based lithium for the past 20 years, SQM knows all too well how supply concerns and fluctuating prices can affect market sentiment. The Chilean-based company has become the world’s largest and lowest-cost producer of lithium and has seen the sector flourish and dynamics change. 

Looking ahead, it is positive the market is set for another exciting period of growth in the mid- to long term. Certainly, lithium will perhaps never be more in demand. 

Typically, lithium hydroxide is used as a thickener and is found in around 70% of lubricating greases, while the growing e-mobility megatrend has increasingly seen it siphoned away for battery production in recent years. 

Just a decade ago, energy storage represented only about a quarter of overall lithium demand, but this has since soared to 65%, largely due to the widespread adoption of the electric vehicle. 

SQM says the perfect storm of increased consumption and constrained supplies saw lithium prices spike in 2017 and triple in value. Yet while spot values have halved since those highs, thanks to lower-than-expected demand and the addition of new production capacities shifting the sector into oversupply, the company believes the market may now have bottomed out and that prices will soon start to bounce back.

SQM, given its size and scale, will ensure its customers continue to receive a quality product with competitive and transparent indexed pricing. SQM’s goal is to continue being a leader in the lithium market and grow enough to be able to support the grease industry in the long term.

SQM produces lithium hydroxide for greases at its Salar del Carmen plant, near Antofagasta in the Chilean desert, and over the years has also grown its production capabilities globally through ongoing investment.

SQM says its strong balance sheet has allowed it to commit 25% of its $2 billion turnover to expanding its output, modernizing facilities and developing new technologies. Among its most recent projects is a joint venture to add capacity in Mount Holland in Western Australia. 

Its ability to adapt and enhance its production process has also enabled the business to deliver better solutions to its customers, it says. 

Rather than supplying typical industrial-grade lithium hydroxide, for example, higher quality bespoke products with fewer impurities and longer-term contracts can also be offered, suited to individual requirements. This has been welcomed by clients, removing the need for them to have to further process the lithium themselves in house or involve a third party – saving both time and money.  

SQM’s North American office is in Atlanta, GA. To find out more, email sales.iod@sqm.com, call 770 916 9400 or visit https://www.sqm.com/en/productos/litio-y-derivados/