Selecting a high temperature grease – what to look for

While you’re working in a machinery situation where the temperatures get a little heated, selecting the best grease is a critical determination to get right. How do you make the best choice?

The internet has some excellent resources out there that can help guide you to making the right decision.

One such resource is the Machinery Lubrication web site, where we discovered an excellent primer on all the factors that it’s worthwhile to consider in selecting the suitable kind of high temperature grease.

While you’re working in a machinery situation where the temperatures get a little heated, selecting the best grease is a critical decision to get right. How do you make the suitable resolution?

The internet has some wonderful resources on the market that may assist guide you to making the right decision.

One such resource is the Machinery Lubrication web site, where we discovered a wonderful primer on all of the factors that you could consider in choosing the right kind of high temperature grease.

deciding on a high temperature greaseWe’ve referenced a lot of that information here.

For the full article, check out Machinery Lubrication’s web site here.

What To Consider?

There are various criteria to consider when choosing a high-temperature grease for decent, grease-lubricated equipment – oil type and viscosity, oil viscosity index, thickener type, stability of the composition formed by the oil and the thickener, additive composition and properties, ambient temperature, working temperature, atmospheric contamination, loading, speed, relubrication intervals, etc. With the number of details to resolve, the collection of greases that should accommodate extreme temperature conditions is a challenging determination, and given potential for incompatibility problems and the high costs for many high-temperature grease, you really must be selective and discriminating when making the decision of which grease to use.

‘High temperature’ is relative when characterizing temperature conditions. Bearings running in a steel mill roll-out table application could also be uncovered to process temperatures of a number of hundreds of degrees, and may experience sustained temperatures of 250ºF to 300ºF (120ºC to ±150ºC). Automotive assemblers dangle painted metal parts on lengthy conveyors and weave them through giant drying ovens to dry painted metal surfaces. Working temperatures for these gas-fired ovens are maintained around 400ºF (205ºC). You may see that there’s a wide temperature range to consider here.

In these cases, the choice factors differ appreciably. In addition to heat resistance, the grease to be used in a scorching steel mill application may require distinctive load-carrying capability, oxidation stability, mechanical stability, water wash resistance and good pumpability, and at a price suitable for big-quantity consumption. With all the necessary factors to consider, it is useful to have a grease selection strategy.

The place To Start?

A reasonable starting level for selecting a high-temperature grease is to consider the nature of the temperatures and the causes of product degradation which can be inherent to no matter place you’re going to be utilizing it. There’s common correlation between a grease’s helpful temperature range and the anticipated value per pound. As an illustration, a fluorinated hydrocarbon-based (type of artificial oil) grease may work successfully as high as 570ºF (300ºC) in house applications however may additionally cost hundreds of dollars per pound. How well the grease holds up lengthy-term is influenced by the causes of degradation, three of which are particularly essential: mechanical (shear and stress) stability, oxidative stability and thermal stability. Oxidative and thermal stresses are interrelated. High-temperature applications will typically degrade the grease by thermal stress, in conjunction with oxidative failure occurring if the product is involved with air. This is comparable to what is to be expected with most industrial oil-lubricated applications. Bell Performance’s X-tra Lube Grease provides some advantages in these types of situations because of the residual lubricating energy of its additive package, that continues providing lubricating protection after different parts of the grease could have broken down as a result of these factors in normal use.

What’s In A Grease?

high temperature greaseFor the uninitiated, grease consists of a base oil with a thickener added, plus further additives thrown in to bulk up sure essential properties of the grease. Think of the whole thing like a sponge – the thickener is the spongy materials that holds the bottom oil together like a sponger holds liquid.

Base Oils

When choosing lubricants for oil-lubricated applications, one typically begins with the consideration of base oil performance properties. This can be an excellent starting point for grease products. Base oils might be subdivided into mineral and synthetic types. Mineral oils are probably the most widely used base oil part, representing approximately ninety five percent of the greases manufactured. Artificial esters and PAO (artificial hydrocarbons) are subsequent, followed by silicones and a few other unique synthetic oils.

The American Petroleum Institute divides base oils into five classes primarily based on their performance limits (Teams I-V). They tend to differ by how well they resist thermal or oxidative break down, and the way well they disperse and hold the additives which can be added to the grease product. Generaally speaking, the higher Teams are more resistant however cost more.

Mineral and synthetic base oils degrade thermally in conjunction with oxidative degradation if the product is involved with air. The break level at which the individual oil molecules in a highly refined (Group II+, Group III) mineral oil and artificial hydrocarbons will start to unravel, releasing carbon atoms from the molecular chain, is about 536ºF to 608ºF (280ºC to 320ºC). three,4 The grease producer will choose supplies given their familiarity, and perhaps availability, of the raw materials. If the producer makes a particular type of artificial base fluid and is intimately familiar with the varied destruction mechanisms of that fluid, then it is likely that this type of artificial base will usually be chosen for new product development.

Thickeners

The materials chosen because the grease thickeners may be organic, equivalent to polyurea; inorganic, resembling clay or fumed silica; or a cleaning soap/complex cleaning soap, comparable to lithium, aluminum or calcium sulfonate complex. The usefulness of the grease over time will depend on the entire package together, not just one thing like the thickening system or the type of base oil. For example, a silica grease thickener has a dropping level of 2,732ºF (1,500ºC) as one excessive example. However, because grease performance depends upon a mixture of materials, this does not characterize the helpful temperature range. Some examples of the kinds of thickeners you will have to choose from could be:

Organic polyurea – provides temperature range limits similar to the metal cleaning soap-thickened grease, however additionally it has good antioxidation and antiwear properties that come from the thickener itself. Polyurea thickeners might grow to be more widespread but they are difficult to fabricate, requiring the dealing with of a number of toxic materials. While the thickener has a high dropping point, the composition begins to thermally degrade at temperatures which limit its usefulness over time at high temperatures.

Calcium sulfonate – similar to the polyurea, it possesses inherent antioxidant, rust-inhibiting properties, but in addition has inherent high dropping points and EP/antiwear properties.

In the event you adored this article along with you wish to receive more details concerning จารบีทนความร้อนสูงยี่ห้อไหนดี i implore you to pay a visit to our own web-site.