Hydraulic equipment are critical to the procedure of many elements of contemporary life, from massive plants that count on hydraulics come manufacture components to the hydraulic device that powers a neighborhood garbage truck. As massive and powerful as these systems might be, they do have actually a proverbial Achilles heel: temperature extremes. Both low and high temperatures can impact the performance and efficiency that hydraulic systems, both big and small. If your system is no performing as expected, maybe it is an problem with temperature that requirements to be investigated and addressed.

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Low-Temperature operation Conditions


When most people think the the impacts of temperature on hydraulics, their instant thought is heat; however, cold temperatures can have a damaging effect ~ above hydraulic systems as well. Such sub-optimal operation temperatures can result from well-below-freezing ambient temperatures or the procedure of a hydraulic system at high-altitude, low-atmospheric conditions. Low-temperature impacts can be particularly problematic for mobile hydraulic systems found on the end equipment during the winter months.

Effects of short Temperatures top top Hydraulic Systems

Elastomeric materials like rubber are typically found on hydraulic solution of all sizes, and also rubber (as well as other types of elastomers) is perceptible to cold temperatures and also can behave together a brittle material when temperatures drop sufficiently low. Once hydraulic equipment is exposed come cold temperatures, rubber materials such as seals, fittings, mounts, and also hoses deserve to be serious damaged throughout operation. It is essential to inspect the condition of exterior rubber components for crack or tears before beginning the device and always have replacement parts on hand because that rubber materials just in case something is damaged.

Cold temperatures will affect the viscosity the the fluids in her hydraulic system, which means not simply the hydraulic fluid however lubricants. Short temperatures will increase the viscosity of hydraulic fluid and oil, which method that it will certainly behave as a thicker fluid. If the viscosity increases too much, the fluid will not behave normally; because that example, top top startup, oil v a greater than regular viscosity may not distribute evenly around critical parts fast sufficient to avoid damage. Store in mind that fluids deserve to actually congeal to the suggest where they will no much longer flow. This will an outcome in starved pumps, cavitation, and also lack that lubrication, subsequently leading come expensive damages to your hydraulic equipment and also the components it is consisted of of.


A wise practice is to examine the fluids in your hydraulic tools — including not just the hydraulic liquid but also engine fluid and also transmission liquid — before starting it up. You space not check the levels, but rather check the viscosity: if the liquid is too thick come drip off the end of the dipstick, that is as well viscous to function properly. Do the efforts to run your device in that problem will seriously damage it. This boost in viscosity is also why the is important to provide your hydraulic equipment a opportunity to warm up prior to use. Start up the equipment and let that idle in order to heat up the hydraulic system and also the fluids that it relies on prior to you put the equipment to work.

In general, it is important to make certain the fluids used in the mechanism are appropriate for the intended temperatures, taking right into account atmospheric pressure if high altitude problems are involved. Manufacturer guidance need to be sought if over there is any type of question regarding what form of fluids are suitable in cold temperatures.

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Effects the High temperatures on Hydraulic Systems

When hydraulic fluids and lubricants are exposed to high temperatures for prolonged periods the time, the fluids will start to experience irreversible deterioration and a major reduction in viscosity (i.e., the fluid will be much thinner and less viscous). The deterioration of hydraulic fluid leads to oxidation (in fact, the oxidation price itself substantially increases v temperature) and the formation of problem sludge. At the very same time, the liquid will experience chemical reactions in between degrading additives, all of which seriously weaken the performance of the fluid and also the hydraulic device as a whole.

The lessened viscosity have the right to render lubricants and hydraulic oil useless once it concerns protecting materials through to reduce friction, staying clear of abrasive damage, and also minimizing the rate of wear. A change in viscosity additionally affects the actions of the hydraulic liquid itself, negatively impacting the power of the hydraulic system as a whole. Relying on a mix of pressure and also temperature, some fluids may actually reach a vapor state — which will certainly obviously lead to damaged systems and also components.


While the usage of a hydraulic liquid that contains a vi (Viscosity Index) boosting additive may alleviate the trouble of lessened viscosity in high temperatures, it is an important to psychic that prolonged exposure to high temperatures can reason this very additive to malfunction — definition that VI improving additives are not an easy solution to the problem. Even more interesting is the reality that prolonged high-temperature procedure can deplete other an essential additives, including foam depressants, rust inhibitors, antiwear ingredients, and antioxidants.

As fluid deterioration continues and vital additives such together rust inhibitors and also antiwear ingredients start to deplete, then the components within the system (hydraulic motors, pumps, valves) will start to experience increased wear. Mechanism performance and efficiency proceed to drop and the system will begin generating its very own heat. The an outcome is a lethal cycle of damage to your hydraulic system as a whole and also the contents within. If the sped up wear is permitted to continue unhindered, then bits the surface steel may begin to undertake away, creating flakes and also tiny particles that will certainly contaminate the hydraulic fluid and also exacerbate the wear.

In short, extended exposure come high temperatures can ruin a hydraulic device over time.

Causes of warm Generation in Hydraulic Systems

High temperature can an outcome from extreme ambient temperature but are much more likely to be the an outcome of warm generation within the hydraulic system. Due to the fact that heat deserve to be for this reason damaging to a hydraulic system, it is vital to track down the resource of warmth generation. Warmth generation commonly results from liquid flowing from an area that high push to one area the low pressure without any output of mechanically work. One resource of together a loss of push is friction. High friction in the device will generate heat, and sources can incorporate the following:

Improperly lubricated contents (e.g., not sufficient lubrication or no the best kind)Use the a liquid with also high a viscosity because that the system, leading to friction within the fluidUse that a liquid with too low a viscosity that stops working to defend surfaces from excessive wearPressure set off piston sealsFluid passing v a constricting orifice or restriction in ~ high speedFluid flowing v a minimal passage

Other warmth sources can encompass the compression that aerated fluids, which occurs when the hydraulic fluid is contaminated with air. The compression that aerated liquid within a pump can easily lead to temperatures approximately 2000°F.

In part cases, the heat may no be created by the system itself. If the hydraulic system is operating close to a warm source, the could reason problems because that the hydraulic system. A absence of proper ventilation have the right to also result in elevated temperatures.


Temperature extremes will influence the power of her hydraulic system and an outcome in serious (and expensive) damage if nothing is done to either attend to the temperature issues or defend the system from the impacts of the temperature. This is true whether it is a tiny snowplow operating throughout extremely cold ambient problems or a hydraulic mechanism in a manufacturing plant the is generating enough heat come raise its operation temperature past recommended limits. The many immediate result of temperature involves the viscosity of the fluid: cold temperatures will certainly increase fluid viscosity, making the thicker; high temperatures, top top the various other hand, will certainly decrease the viscosity that the fluid. Such changes in viscosity can easily lead to permanent damage to the hydraulic system and also its components.

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Changes in performance deserve to be because of operating temperatures, and addressing those worries for high temperature cases involves some investigative work-related to identify the resource and reason of the warm generation.

MAC Hydraulics

As one of our plenty of services, MAC Hydraulics uses on-site maintenance of hydraulic systems and equipment with fully equipped business vehicles and also skilled technicians who only job-related on hydraulics. Our knowledgeable technicians will perform liquid analysis, inspect and also replace hydraulic hoses, inspect fluid levels, change filters, and also perform other necessary maintenance tasks. If friend have troubles — consisting of temperature problems — any kind of time, day or night, MAC Hydraulics will send out among our technicians to inspect, troubleshoot, and address your hydraulic problems using state-of-the-art equipment they have been trained come use. We even offer machining and also welding solutions as needed. Whether you have a tiny hydraulic system on mobile tools or a massive, complex hydraulic mechanism that is the love of her plant, contact us this particular day to see just how our technicians can help you construct the best maintenance arrangement for your hydraulic machinery!