Author: Cameron Ballentine
On our path to becoming the most trusted and dependable compressed air equipment provider in Norther America, we at FS-Curtis have just taken another major step forward.
FS-Curtis is proud to announce the newest addition of our Nx Rotary Screw Air Compressor Series. The Nx18-37 kW (25-50 hp), is now available in Variable Speed Drive! The NxV 18-37kW variable speed drive compressors are built on the same reliable platform as the fixed speed product introduced earlier this year. There are, however, some notable differences. These compressors are controlled by a variable speed drive to match energy consumption to demand, they utilize a robust direct drive arrangement, and the iCommand Touch controller is now standard on the 18-37 kW Variable Speed Drive units at no additional charge. With the standard iCommand-Touch, a full-color screen displays graphs which capture and track factual, real-time air usage by the hour, day, week and month. Historical data can be retrieved at any time with a touch of the screen. The data trending keeps your finger on the pulse of your entire compressed air system.
Introducing this new addition to the FS-Curtis Rotary Screw lineup continues to show that through the dependability of our people and our quality-focused manufacturing, FS-Curtis will continue to be a trusted name serving even more markets through our ever-growing global presence.
In order to help us grow in our mission, we welcome your feedback to help us improve and exceed your expectation.
The FS-Curtis Sales and Marketing Teams
Here’s What You Need to Know
If you’ve been in an auto body shop recently (which is unfortunate because it probably means you’ve had fender bender) or a small manufacturing operation, you may have heard the not-so-inconspicuous hum and rattle of an air compressor. More than likely it was a two-stage compressor. Why not a single-stage? Generally, single-stage units are for less demanding operations like home garages or construction job sites where the distinctive pop, pop, pop sound of nail guns pierce the air like firecrackers on the 4th of July. Nail guns or the occasional use of a rachet gun only require single-stage compressors.
So, why would you need a two-stage air compressor? There are three main reasons:
- Redundancy – If one pump/motor fails or needs service or repair, the other pump/motor can continue to operate, avoiding downtime. Important for any business. Your air flow may be cut in half, but it's better than shutting down your business while the compressor is service.
- Electrical Limitations – What if you absolutely need a 10-15HP compressor but three-phase electrical service is either not available or too expensive run? A duplex compressor with single-phase pump/motors would be your solution.
- Varying Air Usage – If you’re air needs, CFM, fluctuates throughout the work day, where one minute you’re using a small hand tool and the next a sand blaster, a two-stage compressor is perfect to help regulate air flow. When air consumption needs are low, only one pump/motor will operate on your two-stage compressor, but both pumps kick in when demand increases. Smart little boogers, aren't they.
If you’re in the market for a new two-stage compressor, here’s what to look for before you commit.
Definition: One HP is the force needed to lift 550 lbs. one foot in one second.
With all the hubbub made over HP, the CFM (cubic feet per minute) your compressor can generate is actually a more critical factor. But, it’s true that generally speaking, the more HP you have, the more CFM it can produce, so there is a direct correlation that can’t be overlooked. That said, it’s more prudent to shop by CFM, not HP.
CFM (cubic feet per minute)
Every air tool in your shop has a specific CFM requirement—the higher the CFM, the more air volume the tool uses. Keep in mind that if you’re a furniture shop then your sanders will require more air than nail guns.
Take an inventory of CFM requirements for each tool, and the number of everyday tools, and then calculate your necessary CFM, regardless of whether they will all be operating at the same time or not.
Single-phase? Three-phase? What’s the diff?
Generally speaking, single-phase electrical is found in residential settings. Three-phase in commercial buildings, manufacturing operations, etc. So, obviously your first consideration whether to choose a single-phase or three-phase compressor is based on where you will be using it.
Sidenote: Three-phase electricity is considered to be more efficient and therefore could result in less wear and tear on your compressor’s motor.
Keep in mind that electrical codes, voltage and phase vary widely geographically so be sure to check your local building codes and with an electrician before laying out that credit card.
So, now how big of a tank do you need for your compressor? How many gallons?
With two-stage compressors tank sizes range from 60 – 200 gallons. The size of your tank should be basedon how often the compressor will be in use.
This should give you enough to go when choosing your next, or first, two-stage compressor and enough ammunition to ask intelligent questions.
If you should have questions regarding purchasing a two-stage compressor, call our customer service department and we will be happy to assist you: 800-925-5431. Or, visit us online at: us.fscurtis.com
Click on the icons below to download product information about FS-Curtis reciprocating compressors.
How One Food Processing Plant Saved $150.000 Annually
According to the Advanced Manufacturing Office in the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), American industries spend $5 billion annually on compressed air. In the case of food plants, costs are not documented, leaving compressed air systems principal candidates for waste and abuse.
Follow these 5 steps to save your food processing plant enough money by the end of the year that you'll be glad you took five minutes to read this article.
- Examine and analyze your compressed air system
Note all the uses of compressed air in the plant and all the air compressors available by enlisting the help of engineers and technicians, and then:
Conduct a self-audit of your compressed air system
There are 10 most important targets to evaluate in a compressed air system audit:
- Estimate actions to repair deficienciesCorrect the problems that are the least expensive to repair. Using a Pareto diagram can be useful to help separate the “critical few” deficiencies from the “trivial many” possibilities that are available. For example, the Pareto diagram is shown in figure 1, where the solution for the problem is listed on the X-axis (Improvement). The Y-axis (Savings) shows the estimated savings (less costs) that would result from repairing the problem. Projects shown in the tallest bars should be choosen for implementation.
Figure 1: Pareto diagram helps to select the most effective actions.
- Implement the best solutionsAfter identifying the best alternatives in step three, it is time to execute. Beware that some processors postpone taking action because of time constrains, but it may be worthy to hire extra help to carry out recommended solutions right away. Every action should be measurable in terms of cost and savings.
- Track resultsAll solutions that were implemented should be reviewed regularly to ensure that the results are as expected, or to find out if something has changed or requires additional attention. Once recommnded changes are made, then the five-step process can be repeated to double check yourself.
If you think your company could benefit from having a compressed air system audit performed, viist this link to find a distributor in your area to inquire about scheduling an audit. You can also call our toll free number to talk with a customer service rep about locating an FS-Curtis distributor in your area: 800-925-5431.
Click icons to download product literature for compressors used in the food processing industry.
Check out this article: Food industry factory saves $154.000 in annual energy costs, to see how one plant was able to save over $150.000 annually in energy costs.
Source: Oklahoma State University. Food technology fact sheet.
Question: Would you dump lawnmower oil into your car's engine? Probably not. Your neighbor's, maybe, but not your precious heap of a jalopy.
Same strategy holds true for your air compressor. Just like automobile oil, there are many different grades of air compressor oil to choose from, each designed to meet certain specifications.
Two main factors are involved in choosing the correct oil:
1) The type of compressor. Rotary screw or recip?
2) The environment your compressor operates in. Hot, humid temperatures? Cold? Dirty air? Clean, sterile environment?
Many compressors, many environments, many choices.
Solution? Of course there is. What's a riddle without an answer.
To help ease your pain when choosing oil for your compressor, FS-Curtis has introduced two new fluid lines: FSC-Max Fluid and Pro Fluid.
FSC-Max Fluid is our core fluid product line and comes with a bold new look. Designed to offer the highest protection for your FS-Curtis products and to operate at 100% efficiency in virtually all environments, FSC-Max will help run your unit efficiently and smoothly in various environments from food grade applications to large industrial.
How much faith do we have in the FSC-Max Fluid line? All FS-Curtis products are tested and shipped from our headquarters and plant in St. Louis, MO., using FSC-Max Fluid.
It's also the only lubricant product line that can validate FS-Curtis extended warranty programs.This is important in order to protect your investment and ensure its longevity.
Pro Fluid is a great new addition to our professional grade line of products and offers a full range of fluid choices for virtually all circumstances. It is also an ideal economical alternative for OEM replacement fluids, and a great choice when servicing industrial machinery.
For more information about which fluid is the best choice for you compressor, ask your FS-Curtis sales representative, call our service representatives at 314-383-1300 or visit our website at us.fscurtis.com
Let’s say you buy a Volvo, arguably considered one of the safest cars on the road, and you drive it 70mph into a brick wall (by the way, don’t do this, it ruins the paint job), is it the car’s fault that it may no longer run?
The same scenario applies to equipment. If the OEMs installation recommendations are not adhered to, there will be a high degree of probability that the compressed air equipment will not be reliable, will not experience the stated longevity, may require above average maintenance, may consume more electrical energy than required and may not consistently provide the compressed air quality required by production.
While it’s impossible to cover all of the things you need to consider when installing a Rotary compressor (and we hope it’s an FS-Curtis), this short article is intended to help avoid the equivalent of driving your car into a brick wall.
1) Have your system voltage measured. The most common electrical utility voltages in the United States are 200 volt, 208 volt, 230 volt, 460 volt. Electrical utilities guarantee a voltage supply tolerance of + 10%. For example, if the voltage stated supply is 230 volts it could measure at any given time from 207 up to 243 volts. Most electrical utilities attempt to hold the supply voltage to + 5%. Operating electrical motors off design or away from their nameplate voltage will generate additional heat leading to reduced motor life expectancy. The majority of induction motors, 5 hp through 600 hp supplied to the U.S. market, are 230 & 460 volts; however, 200 & 208 volt systems are becoming more popular. If a 230 volt nameplated motor is operated on a 200 to 208 volt system it will operate in an elevated heated condition leading to extremely reduced motor life. This is not a recommended practice. There are motors specifically designed for 200 & 208 volt operation. For these applications motors nameplated as such should be used.
2) Many air compressors operate into the motor service factor. As such, request the package full load operating amp draw from the manufacturer to properly size the electrical utility supply equipment (i.e., wire, electrical quick disconnect, overloads, transformers). Seek out a qualified electrical contractor in your area to assist in proper electrical utility modeling and sizing.
1) Proper placement and mounting is vital. Request a General Arrangement (GA) drawing from the OEM for each piece of compressed air equipment purchased. The GA drawing should illustrate the weight and recommended clearances to be maintained around the equipment. The floor will need to support the static weight of each piece of equipment. The equipment should be secured to the floor to prevent it from shifting around imparting stress on connected utilities such as piping, electrical and ducting. In addition, many states have adopted seismic codes mandating equipment be structurally secured to the floor. Many floors appear flat to the eye but are not flat enough to meet accepted equipment mounting practices. Many floors can be crowned (bowed) or have undulations. When securing equipment to a floor it is important to identify floor imperfections filling the air gaps with shims. When properly shimmed, the tightening of the mounting bolts will not bend or distort the equipment frame. Frame distortion will lead to excessive equipment vibration. Excessive vibration causes premature component failure which reduces machine reliability, increases cost of ownership and could potentially create an unsafe situation.
Proper clearances should be adhered to. These recommended clearances provide boundary area around the machine for safe, effective operation and servicing of the machine. This boundary area also allows adequate cooling airflow around the machine.
All piping should be properly supported as to not impart stress on the equipment. When connecting piping to the equipment pipe connector, it should be supported with proper tooling to prevent the equipment connector from turning during the piping tightening process. If the equipment receiving connector is allowed to turn (rotate) it very well could damage internal components to the equipment. Air piping should be properly sized and configured to prevent short cycling of the air compressor controls. A rule of thumb is to always use piping at least the size of the supply connection of the air compressor. If the dryer connections are larger don’t worry, the reason could be the dryer is oversized due to rerating or simply the fittings are larger to slow the compressed air velocity down through the dryer. The piping exiting the dryer can be the same size as the air compressor connection or the outlet piping size of the dryer can be used to establish the piping downstream of the dryer.
If the ambient air conditions can drop below 32°F measures should be taken to prevent the compressed air equipment from being exposed to this as it will freeze up. During air compressor operation the most effective way to condition the room temperature is to use the heat generated by the operating air compressor(s). Excessive heat can be discharged from the room by way of a properly sized wall fan. The wall fan can be thermostatically controlled to keep the room at a constant temperature. If there are times when all of the compressed air equipment is not operating, an auxiliary heating system should be considered.
Air-cooled rotary screw air compressors reject 2545 btus/hr per horsepower. Example: A 50 horsepower air cooled rotary screw air compressor rejects 127,250 btus/hr into its surrounding environment. That is enough heat to keep a 1500 square foot home comfortable in the dead of winter with outdoor temperatures below 32°F. Many of these air compressors are installed with little thought of eliminating heat build-up around the air compressor. The heat rejected into the ambient air surrounding the air compressor is continuously cycled through the heat exchangers elevating the temperature. Unchecked, the temperature will rise to an unacceptable level, eventually overheating the air compressor & shutting it down. Ducting can be attached to the air compressor to directly route the cooling air discharge outdoors or away from the air compressor. Wall or ceiling fans can also be strategically placed in the room to exhaust the hot cooling air outside. Either way, an adequate amount of replacement cooling air must be brought into the room.
All installations have contaminants in the ambient air. Contaminants can negatively impact an air compressor in many ways. Two critical ways are indigestion into the air compressor itself with the other being fouling of the air cooled heat exchangers. The best way to determine if the air compressor is digesting an abnormally high amount of contaminants is to consistently perform oil analysis. The oil analysis should look for components not normally part of the oil make-up. The results need to be properly interpreted.
In the case of a lubricated rotary screw air compressor, all of the ambient air drawn into the machine for compression flows right past or through the airend bearings. Too much ingestion of particulate will damage the bearings. The oil not only cools the air during compression it also washes the contaminants out of the air. Over time these contaminants will build up continuing to be cycled through the bearings. For example, a 10 micron particle should be able to flow through an anti friction bearing suspended in the oil film without damaging the bearing surfaces. This does not account for multiple particles clumping together, which will damage the bearing surfaces. Two solutions for reducing digestion of contaminants are to install an air filter with a lower micron rating and higher efficiency rating. The ratings should be adjusted until the oil analysis indicates the level of contaminants is satisfactory. Remember, as the rating of the inlet air filter is increased the surface area should also be increased or the air filter may have to be changed out too frequently from excessive fouling. The second solution is to relocate the inlet air filter to a remote environment which is cleaner than the immediate area around the air compressor. The piping used to remote mount the air filter should be non-ferrous. PVC works great as it is light, easy to assemble and inexpensive. Connect it to the air compressor air end with an easily removable joint in case machine repairs or troubleshooting is required. The piping i.d. should be no smaller than the i.d. opening in the OEM supplied inlet filter mounting assembly. For every 10 feet of inlet pipe run, the pipe diameter should increase one size or 1". If the inlet air filter is relocated outdoors it should be protected from digestion of rain or snow.
Relocation of the inlet air filter is a recommended solution when the surrounding ambient area around the air compressor contains hazardous vapors or fumes. There are air filters which can remove hazardous fumes or vapors; however, they are costly to purchase and maintain.
If you’d like more information about FS-Curtis rotary screw air compressors please follow this link FS-Curtis Rotary Screw Air Compressors. I you have questions or would like more information or pricing, please visit our Distributor Lookup page on our website to locate a distributor in you area.
A Variable Speed Drive compressor sounds like a smart idea, but is it really?
Earlier we posted a blog on why rotary machines are often not ideal applications in auto care shops – CLICK HERE TO GO TO THAT POST. Now let’s address another rotary compressor question that auto care facilities ask us on a regular basis: Should I spend the extra money to put an energy-saving Variable Speed Drive (aka: Variable Frequency Drive) rotary screw compressor in my facility? The short answer to this question is: probably not.
The folks asking this question have heard that VSD/VFD machines may cost more up front but that they cost less to run and thus pay for themselves in the long run. In addition, many utility companies offer rebates for VSD/VFD machines that can help offset the larger up-front cost. Just like everyone else, automotive care facilities want to save money and energy, so this supposed value proposition sounds attractive. Right?
So why then is VSD/VFD probably not a good idea for most automotive care facilities? The short answer is that most automotive care facilities typically have severe peaks and valleys in their compressed air usage due to the intermittent use of tools and equipment in the shop. This in itself does not rule out VSD/VFD. In fact, VSD/VFD is ideal for customers whose demand fluctuates, provided that it does not fluctuate too much. The problem with auto care facilities is that their valleys are too deep. Too much downtime. The rule of thumb is that when the valleys are 30% or less of the peaks, the compressor will have to shut down, essentially forcing it to run as a start/stop machine. There are several issues with running a VSD/VFD machine in this type of application:
- More expensive – First of all, the customer is paying a 30% or more premium for a VSD/VFD machine to run just like a cheaper start/stop fixed speed machine. Perhaps the more important comparison is that the customer would be paying a whopping 70% premium compared to a fully-loaded UltraPack recip, which is probably the best application in most auto care shops.
- Phantom Energy Savings – VSD/VFD machines are ideal for loads somewhere between 30 and 80 percent of full load. There are little to no energy savings otherwise. Even though very short payback periods are often cited, these are for machines in ideal scenarios with exactly the right load profile. Auto care facilities very seldom have an appropriate load profile. If one isn’t going to get the benefit of the VSD/VFD, why pay extra for it, and risk some of the potential headaches outlined below?
- Increased Maintenance -
o VSD/VFD’s require minimal incremental maintenance on the drive compared to standard fixed speed machines. These increased costs should be considered in any decision to go with a variable speed machine.
o VSD/VFD’s require a cleaner environment for the sensitive electronics of the drive. This can lead to increased maintenance costs and possibly drive replacement, which is very expensive. If the machine is going to be placed in a shop with dust and other contaminants floating in the air, then the cost of protecting the drive from these contaminants, or paying extra for maintenance and/or replacement, must be considered.
The bottom line is that most auto care applications are not ideal for VSD/VFD machines. The severe valleys in demand profiles mean there probably won’t be energy savings to offset the increased acquisition and maintenance/replacement costs. In addition, most shops are too dirty to install a VSD/VFD without increased risk and cost.
If you would like more information on fixed speed compressor options, click here to compare different options. If you still think a VSD/VFD makes sense, or if you have further questions about our machines (e.g. What is UltraPack? Duplex?) visit our YouTube Library, our distributor portal, our website, or simply call us at 800.925.5431.