Category Archive: Uncategorized
When it comes to hydraulic fluid, it’s not possible to make one, definitive recommendation that covers all types of hydraulic equipment in all applications. But in response to the common question: “What type of oil should I use in my hydraulic machine?”, here are 3 important factors to consider:
Multigrade versus monograde
The operating temperature range of the machine is the factor that determines whether a multigrade or monograde oil is required. If the machine is required to operate in freezing temperatures in winter and tropical conditions in summer, then multigrade oil will likely be required to maintain oil viscosity within optimum limits across this wide operating temperature range.
If the machine has a narrow operating temperature range, and it’s possible to maintain optimum fluid viscosity using monograde oil, I wouldn’t chose a multigrade. Multigrade hydraulic oils are more expensive. And if a monograde oil is used, there is no possibility of loss of viscosity as a result of VI improver shear down.
Detergent versus non-detergent
Detergent oils have the ability to emulsify water, and disperse and suspend other contaminants such as varnish and sludge. This keeps components free from deposits but means that contaminants are not precipitated out – they must be filtered out. These are desirable properties in mobile hydraulic machines which, unlike their industrial counterparts, have limited opportunity for the settling and precipitation of contaminants at the reservoir, due to its smaller volume.
When using an oil with detersive/dispersive additives, it’s even more important to closely monitor water content via oil analysis. Water accelerates aging of the oil, reduces lubricity and filterability, reduces seal life and leads to corrosion and cavitation. And emulsified water can be turned into steam at highly loaded parts of the system. These problems can be largely avoided by maintaining water content below 100 ppm.
Anti-wear versus no anti-wear
The purpose of anti-wear additives is to maintain lubrication under boundary conditions (loss of full-film lubrication). The most common anti-wear additive used in engine and hydraulic oil is Zinc dialkyl dithiophosphate (ZDDP). The presence of ZDDP is not always seen as a positive, due to the fact that it can chemically break down in the presence of water, and attack some yellow metals. However, an anti-wear additive is essential for any oil used in high-pressure, high-performance hydraulic systems.
Fill ‘er up
In summary, choosing the right hydraulic oil for an application is not a quick or simple exercise. And it’s worth taking the time to get this right. Because using the WRONG hydraulic oil can turn out to be a very costly mistake. And to discover six other costly mistakes you want to be sure to avoid with your hydraulic equipment, get “Six Costly Mistakes Most Hydraulics Users Make… And How You Can Avoid Them!” available for FREE download here.
You likely have a busy schedule ahead of you, and with the holidays coming up, there may be little time to pursue the upgrades and repairs you are planning to finish before the year ends. Now would be a good time to take stock of what you need at your place of business and see what hydraulic services are required to increase shop efficiency. Here are the hydraulic services in Minnesota that we offer, and how they can help you:
- Cylinder repair: For hydraulic and pneumatic equipment, cylinders are vital. If they are corroded and not operating well, you risk down time, blown deadlines and unhappy clients. Call us in to inspect your cylinders and repair them before they let you down. We handle small and large cylinders on many different types of machines, so you know these essential parts are in the right hands.
- General machining work: Hydraulic equipment often requires welding and fabrication. Sometimes, a quick repair is needed or a worn out section needs extra attention, and chances are, we have done the same type of work before. Besides checking your hydraulic components, we also offer general machining when you need it.
- Custom parts: You may have an old reliable machine that no longer has new parts made by its manufacturer. Or you might have a shop full of truly unique equipment, and parts off the rack do not work for it. Rather than go through a trial and error with aftermarket parts, we can adapt to the cylinder size and use machining and welding techniques to create the part you need. Very few machines run on a one-size-fits-all template, so contact us today to take the custom approach.
- Prototyping: When you have been in your industry long enough, you’ve likely seen the best and worst in design. You can see where an adjustment will help a part work better, but lack the expertise to do that yourself. If you have ideas for helping your equipment operate, you can hire us to design and test your ideas through prototypes. We offer our own experience in the process, as well, and may find ways to improve on your idea so it performs even better. Our services in general machining, welding and fabrication will leave your tools and equipment in better condition so you can rely on them more fully.
- Rebuilding: When you experience an equipment failure, you can save money by rebuilding cylinders, pumps, motors and valves. It depends on the extent of the damage, but these efforts can restore them to nearly new condition. Allow us to inspect your older machine and find the worn or damaged parts before they fail. We can then start a rebuild immediately and save you the stress and expense of an emergency repair.
- Consulting: You may sense inefficiencies or shortcomings and require an expert opinion. Our consulting services offer just that. Our expert field service troubleshoots issues and recommends changes or upgrades. If you are attempting to make decisions about your next capital investment, have us visit first so you spend your money wisely.
M & M Hydraulic Company is available for hydraulic services in Minnesota, Wisconsin, North Dakota, South Dakota and Iowa. Contact us today for a consultation.
Overheated oil can wear out hydraulic parts quickly in the shops and businesses that depend on them. That is why you should consider adding an oil cooler to keep your hydraulic parts in Minnesota running well and prevent overall machine failure. Here is an overview regarding heat load and how to find the best oil cooler for your equipment.
Understanding hydraulic oil and heat load
Generally speaking, excessive heat compromises the hydraulic oil by accelerating oxidation. That breaks down the oil and produces sludge and varnish, which can both restrict the motion of the components and lead to failure. Since overheated oil cannot normally be handled by workers, changing it out for cooler oil is not an option.
The reason oil becomes overheated is that hydraulic systems perform their purposes very well, but they do not always run efficiently. Input power that is not allocated to output is wasted out as heat. Since hydraulics depend on oil to run, all that heat goes straight to that fluid, which eventually results in overheating.
Designers install a general heat load tolerance of 30 percent of the input power. This is the normal industry standard—however, it is not always appropriate. Other factors can increase or reduce tolerance, so you may find your components start corroding at lower temperatures than indicated in your equipment specifications.
Choosing the right oil cooler
Adding an oil cooler reduces this risk substantially. It will keep the oil temperature at a stable level, which preserves your equipment. Since you likely rely on your machinery performing well throughout the day, this is additional reassurance for your bottom line, as well.
You will base the size of your oil cooler first on input power. This gives you a good idea of the general heat load, so you find an oil cooler that can keep up with it. For example, if you have a hydraulic system with input power of 100kw and it has an efficiency rating of 80 percent, that makes 80kw available for output and 20kw converts to heat. In other words, your oil cooler must be capable of handling that 20kw.
Efficiency of your system must also be considered. More efficient equipment normally does not produce as much heat, and you can likely get away with an oil cooler with a lower capacity.
Finding the right oil cooler is often a guessing game. You want to get approximate numbers but also add a margin of safety in case your component condition or other factors cause it to operate outside manufacturer specifications. Going with a cooler that is too big rather than too small is great for reliability, although it will not save on costs. It all depends on your tolerance for risk and the knowledge you currently have about your hydraulic systems.
For repair and maintenance of hydraulic parts in Minnesota, Wisconsin, North Dakota, South Dakota and Iowa, contact M & M Hydraulic Company. We can address your need for an oil cooler, plus any other shortcomings in your equipment.
For machine shops and other businesses, hydraulic components in Minnesota require regular maintenance to keep working. You also have to be aware of when they need attention and pass that knowledge along to your employees. Here are some common symptoms that require attention and troubleshooting when you detect them:
- Abnormal noise: When your equipment starts to sound unusual, that is often due to aeration. This is when air builds up in the hydraulic fluid. You will often hear banging or knocking, but usually it is just different from the usual noises. Fluid foaming is also common. Check the lines for good condition as well as clamps, seals and fittings. This often happens due to a leak, and once you fix it, the problem will stop. If the fluid reservoir is low, that also leads to air buildup. Top it off while you are inspecting these other parts and check the reservoir to make sure it is not leaking either.
- Knocking sound: Knocking is often a symptom of aeration, but it also indicates cavitation. This is a serious situation where the amount of fluid demanded exceeds the fluid that is supplied. That places pressure on circuits and risks implosion, which could injure workers and damage equipment and goods. You will frequently be able to trace this development to clogged strainers or lines. Clearing these areas normally solves the problem. If there are any isolation valves on your system, check to see if they are opening fully. When lines get old, they also get stiff, which impedes the movement of fluid. Replace them when that happens.
- High fluid temperature: Your hydraulic fluid should not exceed temperatures of 180 degrees. When this occurs, viscosity drops and the fluid will be less likely to perform its functions. You will normally be able to trace this problem to heat dissipation systems. If the reservoir is constantly low due to a clog or leak, that will sometimes raise fluid temperature. However, it is also likely that your heat exchanger is malfunctioning, so consider cleaning or replacing it if you do not find blocked lines. If you do not solve this problem quickly, the fluid will damage seals and reduce the life of your equipment. Consider installing a high temperature alarm to assure that you and your employees become aware of any issues with fluid temperature.
- Slow operation: When machines take longer to cycle, this indicates low fluid flow. This can arise from leaks and clogs, just like the other issues listed above. However, in this case, the leaks are usually internal and difficult to detect. If you notice a pressure drop along with a rise in temperature, there is likely a leak somewhere in your equipment’s interior. You will likely need to bring in a professional to find the leaks quickly before you start compromising the condition of your machinery.
Regular troubleshooting of your hydraulic components in Minnesota will keep your shop or manufacturing operation running smooth. When these problems become challenging, a skilled hydraulic shop will prove essential. For these jobs, contact M & M Hydraulic Company to get your equipment working well again.
Sometimes, despite all the careful maintenance and attention paid to hydraulic parts in Minnesota, there are still equipment failures. Gear pumps tend to make up the more catastrophic failures in terms of expense and down time at shops. Here are five of the most common causes that arise in failure analysis, and how to recognize them before they shut you down:
- Fine particles: Even the smallest debris can damage gear pumps. Fine particles are the most common cause of failure, and this is because we usually can’t see this happening. It starts as a gradual decrease in speed that might not even be noticeable. Then, the buildup of fine particles starts wearing out parts slowly until there is a failure. You can reduce the possibility of this happening by cleaning tank caps, funnels and the area around the filler neck before you top off fluid. If there are lines left disconnected, cover them when not in use. Working in a dusty or dirty environment often leads to this breakdown, so take extra care to keep machinery clean if this is your situation.
- Metal contaminants: Abrasions from metal contaminants occur from wear and tear, but also from insufficient fluid flushing after a previous failure. Unlike the damage from fine particles, which is gradual, metal contaminants may cause slow or sudden failure, depending on the damage they inflict. Fortunately, you can usually detect this situation early by checking for surface scratches on pressure plates. When you see these signs, flush your system again to reduce contaminants.
- Poor installation: Pumps must be installed carefully to ensure they do not handle loads that exceed their capacity. If piping is not connected well or components rub up against each other, your gear pump will wear out and fail. When it is time to replace pumps, hire a professional so you know this task is completed correctly.
- Aeration: When air mixes with the oil, aeration results. While this is a less common gear pump failure, it can cause extensive damage. The air can prevent the needed fluid flow and place pressure on lines and mechanisms. It can also eventually lead to leaks, which can corrode the gear pump. When you start hearing knocking noises, check for air leaks. If these are allowed to build up, your equipment could also suffer cavitation, which will reduce pump suction and cause overheating. This will also lead to eventual failure and expensive repairs.
- Low oil: There are two reasons your pump may suffer for lack of oil. One, your workers forget to refill the reservoir. Put system checks in place so this task is not overlooked. Two, your hydraulic lines and systems could have a leak. Gear pumps cannot work properly without sufficient oil, so keep an eye on this problem until you find a resolution. Sometimes, awareness of the oil level is all that is needed, but if this is being monitored well and you still have an issue, inspect further and consider bringing in a repair technician.
For the care, maintenance and repair of hydraulic parts in Minnesota, contact M & M Hydraulic Company for assistance.
Taking proper care of your possessions is a major part of ensuring they work for as long as possible. If you’ve recently invested in an expensive tool, you definitely want to get the most you can out of it. The more advanced the tool, the more maintenance you need to do on it.
Proper pneumatic maintenance in Minnesota should occur daily, with more intense maintenance coming at the end of each week, and again after 90 days of use.
Daily maintenance
Before you clock out for the evening, you’ve got to make sure your air compressor is good to go for the next day. This means taking a few extra minutes to do some quick maintenance to ensure a properly running compressor.
- Relieve unit pressure: You probably already do this at the end of each day but make sure all of the air pressure in the unit is relieved before you do any maintenance. Forgetting step one can result in serious injury to yourself and anyone else around you.
- Check oil: Next, just like you do for your car, check the engine oil level. You’ll also need to check the oil level of the compressor. If either level is low, add enough lubricant to get it back to normal.
- Drain the tank: After your oil levels are good, drain the moisture from the tank. However, if the tank pressure is over 25 PSIG, skip this step.
- Check for oddities: Finally, take a second to make sure your machine isn’t making any strange noises. Any odd sounds could be the result of problems in the system and require further pneumatic maintenance in Minnesota.
Weekly maintenance
At the end of each week, after you’ve performed the above tasks, you have a few more things to do. While these minor chores will delay your weekend for a minute, they’re absolutely necessary.
- Clean: It’s safe to say that very few people actually enjoy cleaning. However, cleaning is a necessary part of tool maintenance. First, make sure you clean off all of the dirt, grime and dust from the cylinder head, motor, fan blade, air lines, intercooler and tank. Next, clean the air intake filters. You’d be surprised how dirty those can get over the course of a week!
- Adjust V-belts: After you’ve cleaned, you need to make sure the compressor will be in working order for the next shift. This means making sure the V-belts are at the correct tightness, as defined by the manufacturer.
90-day maintenance
After three months, or 500 hours of use, your 90-day maintenance needs to take place. This process will take a bit longer than the weekly and daily maintenance, but is just as important (if not more so).
- Change crankcase oil: Hopefully your engine and compressor oil levels are up to par. Now it’s time to change the crankcase oil. Obviously it’s necessary to use the correct type of oil, as defined by the manufacturer.
- Check for leakage: Using either a high-tech ultrasonic leak detector or just soapy water and a brush, check for air leakage throughout the system. Air leakage can come out of fittings, connections, and gaskets.
- Tighten: Make sure the nuts and bolts are all as tight as the day you bought it.
- Check and clean: Go around and check all of the compressor valves. You’ll probably need to clean them as well.
- Finally: Once all the above steps are complete do one final check of the machine. Pull the ring on all the pressure relief valves. The last thing you want is a failure after all of this maintenance.
If all of the above steps are taken, you should have an air compressor that lasts for as long as you need it.
