One of the leading Russian manufacturers of these grease products is the Elektrogorsk Oil Processing Institute. Viktor Kirillov, head of the institutes’ production unit, said the enterprise has been engaged in manufacturing of polyurea greases since the late 1980s.

“Our own production line has capacity to produce 300 tons of polyurea greases, and the product assortment consists of more than 50 types of such grease and paste products,” he told RPI’s Russia and CIS Industrial Oils and Metalworking Fluids conference held in Moscow May 25. The event was held in person and under strict protocols of social distancing and guidelines to minimize the coronavirus spread.

“The enterprise produces around 60 tons of the Politerm-branded polyurea greases and pastes,” said Kirillov, who is based in the scientific town of Elektrogorsk, not far from Moscow.

The institute found that in 2018, 4.6% of high-temperature application soap thickener supplies globally were polyurea thickeners. In the same year, these thickeners had a 6.4% market share in the United States and a 2.1% share in Europe. Russia consumes about 40,000 tons of greases annually, according to Intesmo, a 50-50 grease production joint venture between oil major Lukoil and the state transportation monopoly, Russian Railways.

About 73,000 metric tons of polyurea grease were produced in 2019, or about 6% of all greases globally, according to the National Lubricating Grease Institute’s annual production survey. About 11,566 tons were produced in Europe. “In Japan, the market for polyurea grease thickeners is much larger, and they account for 21.4% of the country’s total grease thickener demand,” Kirillov said.

The Elektrogorsk institute claims that some of its polyurea complex greases perform well compared to competing products, for example in terms of life expectancy. The company claims to have conducted tests demonstrating a service life of 20,000 hours for one of its low-temperature greases and a service life of 5,250 hours for one of its all-purpose products. Kirillov cited products of several other suppliers with life expectancy ranging from 3,000 to 7,550 hours.

Gost approved Litol-24 lithium complex grease product, a sort of default grease product used in some applications and extensively supplied by many grease marketers in Russia, has service life of just 1,085 hours, while the lithium complex grease products LZ-21 and LS 1P have service life of 1,650 and 2,246 hours respectively, Kirillov said.

Gost is a standard to verify the quality of the production used in the ex-Soviet Union. Its iterations extend well into the post-Soviet industrial development of Russia and many products made in the country are still eligible for sale only if strictly produced under this standard.

The Elektrogorsk institute’s polyurea grease and paste products are used by a number of major Russian automotive, machinery or mining companies such as Nizhny Novgorod-based commercial and heavy-duty vehicle maker Gaz, heavy machinery builder Energomash from St. Petersburg, automotive conglomerates Kamaz from Naberezhnye Chelny and Avtovaz from Togliatti, as well as Norilsk Nikel and the Moscow Metropoliten, operator of the underground transportation system in the capital.

In the West, the polyurea thickeners are considered to be a good alternative to lithium thickeners. For instance, the fine print of the grease product catalogues of many marketers point out that polyurea greases are often the preferred choice for sealed-for-life applications. These greases tend to have high operating temperatures, good antioxidation properties, high thermal stability and low bleed characteristics.

They also have a dropping point of approximately 270 degrees C (518 degrees F). In addition, since their formulation is not based on metal soap thickeners, like lithium greases, which can leave behind wetter sediment when used up, some consider them the preferred choice of lubrication for electric motors.

Experts argue that the biggest drawback is that polyurea thickeners are quite incompatible. This incompatibility can cause hardening or softening of the grease.

“Grease softening can lead to several issues, such as not allowing for proper lubrication of rollers,” according to a news release by Noria Corp., a provider of monitoring and analyses of lubricant and grease products, based in Tulsa, Oklahoma. “Additional grease must then be supplemented to maintain the appropriate lubrication until the incompatible mixture is displaced.”

Hardening of the grease can result in even worse problems, because the grease can no longer flow into the bearing cavity, leaving the bearing starved for lubrication, the company said.

Kirillov said that the polyurea greases show excellent pumpability in centralized lubricating systems.

“They can be used either in extremely low temperatures to minus 79 degrees C, or in high temperatures,” Kirillov said. “They have high water resistance and antioxidant capabilities, can work in wet conditions, such as water steam, acid or alkali solutions and in other volatile conditions.”

He also underlined that polyurea greases can be an excellent substitute for any kind of lithium greases, including the most efficient lithium or aluminum complex greases that work in the temperature ranges from -70 degrees C to up to 250 degrees C.

“The results we got during the bench testing of closed bearings show advantages in the life expectancy of the polyurea greases versus the life expectancy of the lithium greases. Our polyurea greases and high temperature pastes can be an excellent substitute for their imported counterparts,” Kirillov said, adding that the products’ operational properties are the same as the operational properties of their foreign counterparts.