Author: Darryl Frierson
Let’s say you buy a Volvo, arguably considered one of the safest cars on the road, and you drive it 70 mph 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 air compress (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 name plated 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 name plated 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 gives off 2545 btus/hr per horsepower.
Example: A 50 horsepower air-cooled rotary screw air compressor discharges 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 discharged 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.
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 click on the icons below to download product literature. 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 your area.
FS-Curtis and Compressed Air Challenge have come together to provide Distributors with training and advanced training on air compressors. All of this great training and advanced instruction will take place on May 16th-18 in Philadelphia, PA. Also over the next year if you sell a Nx 60-185 HP compressor you will get your registration refunded.
The conference will be held at Courtyard Marriott in Plymouth Meeting, PA
A good accommodation option:
430 Plymouth Rd
Plymouth Meeting PA 19462
May 16th- Fundamentals of Compressed Air Systems
Find out how a compressed air system works and the benefits of optimal compressed air system performance. This initial class demonstrates how to compute the current cost of your plant's compressed air systems, how to measure and create a baseline of system performance, and how to determine the impact of different compressor control types. Learn basic approaches for cutting costs; identify steps for proper system operation, maintenance, and point-of-use accountability; and tailor a compressed air system management action plan for your plant.
May 17-18: Adv. Management of Compressed Air Systems
This is an intensive two-day training that provides in-depth technical information on troubleshooting and making improvements to industrial compressed air systems. This training is designed to help end users as well as industry solution providers learn how to: Collect and use data and tools to assess the efficiency and cost-effectiveness of a compressed air system; Develop and use a system profile; Implement a system maintenance program; Address air quality, highest pressure requirements and high-volume intermittent applications; Understand complex control system strategies; Align the supply side to demand side operation; Explain the value of heat recovery; and Successfully sell compressed air improvement projects to management. When you register, you will be sent an information packet including materials you will complete prior to the training. This information will be critical as you use data to calculate cost and performance in your specific facility.
FS-Curtis introduces the ECO Series Clean Oil Free Air Compressors
St. Louis, MO. March 14, 2017-
FS-Curtis., a leading manufacturer of reciprocating and rotary air compressors since 1854 is proud to introduce the new ECO Series Oil Free Air Compressors.
FS Curtis Eco Scroll oil-free air compressors are ISO 8573-1 CLASS 0 certified compressors which are energy efficient, easy to operate and maintain, quiet and save space in your facility. A failure of components in any oil-injected compressor can result in oil contamination which will cause expensive damage to downstream products and processes. ECO series requires no oil, it delivers Class 0 clean and efficient compressed air, which means that there is no risk of oil contamination or the expenses associated with it.
The Eco-Series has many advantages to assist with new ecological and technological challenges faced by many types of business that require compressed air needs. Some of advantages are:
- Environmentally friendly Class-0 clean and efficient air
- No oil contamination, designed to meet ISO8573-1
- Approved and certified by TÜV Rheinland® (Germany)
- Small footprint, modular design
dbA Shield Noise Reduction
- Extremely quiet operation (as low as 56 dbA)
- Very low vibration level (5 mm/s or less)
- To be installed where quiet setting is important
- Higher reliability - Fewer moving parts
- Exclusive Eco-Series scroll airend
- High Efficiency TEFC motor
- Maintenance friendly
Compressed air requirements have changed drastically as industries push to become ecologically friendly. The Eco Series can help customers in a multitude of different industries meet these changing regulations/requirements:
- Medical (breathing air source*, operating surgical tools)
- Dental (air tools will come in direct contact with the patient)
- Pharmaceutical (fermentation, conveying, mixing, control, powdering, dehydration and vaporization)
- Laboratories (universities, control air, lab air, petrochemical)
Food and Beverage
- Fermentation, Conveying, Dehydration,
- Packaging, bottling, cleaning, filling and capping
- Air sparging/sprinkling
- Assembly, cleaning
- N2 replacement with CDA (clean dry air)
- Oxygen and nitrogen generation
Automotive Painting (Point of use)
- High quality painting, alleviates costly repairs due to oil carry over
*Must be used with approved clean up equipment
About FS-Curtis/CURTIS-TOLEDO, Inc.
Since 1854, FS-Curtis has been designing and manufacturing solutions for industry. The FS-Curtis Air Compressors brand continues to be the symbol of quality and excellence in the design and manufacture of air compressors. Dedicated to customers and loyal distributors, our brand names are synonymous with Legendary Reliability since 1854. FS-Curtis is proud to be ISO 9001:2008 and ISO 14001:2004 certified.
If you would like more information about this product, please visit www.fscurtis.com or contact Darryl Frierson at 314.383.1300 or email at email@example.com.
Pro Compressor, Allentown, Pennsylvania has been in business since 1994. Bob Dietrick owns the successful independent compressor house and has built his loyal customer base by providing exceptional service at competitive prices. Pro Compressor as been an FS-Curtis Distributor serving the Leigh Valley region of Eastern Pennsylvania since they opened for business.
Dietrick began his career in the air compressor industry in the late 70’s selling Joy compressors and Wilkerson air dryers and filters. In the mid 80’s he formed a business with a partner selling Champion and Grimmerschmidt compressors. Then in 1994, Bob started Pro Compressor in his garage at home, building on his loyal customer base and expertise in keeping his customers compressors in top working condition. He selected Curtis Compressors to be his main brand and has been selling FS-Curtis products since that time. As the business grew, he moved operations to the present location on North New Street in Allentown.
The market served by Pro Compressor is the Leigh Valley region which includes Allentown, down to Philadelphia, and north to Pocono Mountain region. The focuses of Pro Compressor are industrial companies such as: metal processing, electronics, wood products, and food and beverage manufacturers.
Today, Pro Compressor has a staff of 4 full-time employees including 2 field service technicians, an inside Sales and Customer Service manager, an outside sales engineer (Bob’s main role) and a Part Time technician. Bob’s son Matt heads up the Service Division. All of Pro Compressor’s technicians are factory trained on all FS-Curtis rotary and reciprocating compressors, as well as FS-Curtis Variable Speed Drive and Electronic controls. So confident in their technical abilities, FS-Curtis regularly calls on Pro Compressor to support customers’ outside of their normal marketing area as needed. Pro Compressor is a valued member of the FS-Curtis Platinum Distributor Council and works with other FS-Curtis Platinum Distributors in advising both marketing and product development projects.
Pro Compressor Web site: http://procompressor.net
Each manufacturer’s make and model of rotary screw air compressor gives specific guidelines for preventative maintenance in the operations manual sent with the air compressor. You’ve invested a good deal of money in your new compressor, to protect your new investment it’s a wise idea to follow these preventative maintenance procedures. Keep in mind this is not a comprehensive list, but it’s a good start and will help give peace of mind knowing you are not neglecting your air compressor.
Every manufacturer of rotary screw air compressors provide an Operators Manual with specific guidelines for preventative maintenance. You’ve invested a good deal of money in your new compressor, to protect your new investment it’s a wise idea to follow the preventative maintenance procedures. Some compressor designs may require more steps and checks, but here is a good place to start to get the longest life out of your investment.
Daily: Check for abnormalities (unusual sound, vibration, leaks, warnings or alarms on the controller, etc.)
- Check oil level
- Monitor temperature and pressure
- Check control panel for any alarms or maintenance lights
Monthly: Perform Daily checks
- Clean inlet air filter and enclosure filters.
- Check operation (load and unload, low and high pressure set-points, maintaining pressure, etc)
Quarterly: Check hour meter and check the maintenance schedule to determine if its time for maintenance to be scheduled. Your compressor may require lubrication change at 2,000, 4,000 or 8,000 hours depending on the manufacturer’s recommendations.
- Take oil sample if needed
- Check separator scavenger line flow (if applicable)
- Check v-belts (if applicable)
- Perform daily and monthly checks
Semi-Annual or 4000 hours: Perform Quarterly Check list.
- Change air/oil separator filters (spin on or drop in type)
- Take oil sample and sent to compressor vendor
Annual or 8000 hours: Start by checking annual maintenance list for manufacturer’s recommendations:
- Change lubricant
- Change air / oil separator (drop in type)
- Perform quarterly checks
Keep in mind; these are the basic maintenance items needed to keep an oil flooded rotary screw compressor in good operation. This preventative maintenance program is designed for a standard condition, but as we all know most installations for air compressors would be considered dirty and dusty environments.
Another factor that is critical to the life of a compressor is the actual run time. All rotary screw compressors underlying guideline for maintenance is hours of operation. Most installations never operate 24 hrs per day / 7 days a week. There are only 8760 hours in a year and anything less than 24 hours will result in lower hours, which affect the amount of maintenance needed for each installation.
So, with all of these factors to consider, what does an owner of an oil flooded rotary screw compressor do to properly maintain the air compressor to ensure long reliable operation?
To answer this question we need to look at several factors:
First the environment is the one factor that governs all of the others. If your compressor is running in a dirty environment where you have to keep cleaning the coolers externally to keep the compressor cool and the air filter is continually dirty when you inspect it periodically; then you have a dirty environment. Use the monthly recommendations and not the hours of run time.
2) Hours of operation (less than 4000 hrs per year)
In this case the recommendation would be to follow the time frame set out for preventative maintenance as described in the operations manual. Use monthly intervals for filter changes and not the hours of operation as your guide. This means air and oil filters changed every quarter (or more frequently) as well as air/oil separators changed per instruction manual. Please note if you are running 24 hrs / 7 days then air and oil filters will need to be changed in accordance with OEM recommendations.
Costs of preventative maintenance should be only considered as a last resort as it has been proven in many studies that preventative maintenance saves money. A proper preventative maintenance program will translate into more reliable operation and less down times for the owner. This will create a more efficient production process for the owner which generates income on a consistent basis.
In all other instances the OEM manual should be used as a guideline for changing all filters for the proper maintenance your rotary screw compressor.
A properly maintained air compressor can be accomplished by following several practical guidelines and discussing your needs with an FS-Curtis compressed air professional. To learn more download the product information or contact your local FS Curtis distributor.
When specifying a compressed air system for optimum operation and energy efficiency, proper selection of the compressed air receiver tank(s) is one of the most critical decisions one can make. There are several different “rules of thumb” and formulas that will assist you, but finding straightforward guidance that says “use this size air receiver” is difficult if not non-existent.
Air receivers can be used in several different ways in a compressed air system:
- “Primary” receiver between the supply side (air compressor and ancillary equipment), and the demand side (your plant). Today’s air compressor controls (on/ off-line, modulation, and variable frequency) strive to maximize energy efficiency and smooth compressor operation by responding to demand side pressure changes sensed at the discharge of the package.
A properly sized air receiver acts as a “buffer” and minimizes the effect of dynamic demand side pressure changes, allowing the compressor controls to operate smoothly and consistently. The end result is less energy used, longer component life, and consistency in plant air pressure.
- “Secondary” receiver typically on the demand side, at the point of use to minimize the effect large intermittent air demands have on the overall compressed air system.
Sizing a PRIMARY receiver for general FIXED SPEED APPLICATIONS:
- The air compressor industry has widely accepted the general rule of thumb that a properly sized air receiver for a fixed speed compressor should be between 1-2 gallons per CFM output of the compressor.
Example: a 100 CFM fixed speed air compressor should have an air receiver between 100-200 gallons sitting next to it. Err on the high side if your budget permits.
Sizing a PRIMARY receiver for general VARIABLE SPEED APPLICATIONS:
- When considering air receiver sizing on a variable speed drive application, the general rule of thumb is between 2-4 gallons per CFM output of the compressor.
Example: a 100 CFM variable speed air compressor should have an air receiver between 200-400 gallons sitting next to it. Err on the high side if your budget permits.
Useful Air Receiver Sizing Formulas (Primary and Secondary):
Use this formula when you have an existing air receiver
and need to know how long you can draw CFM greater than the output of the air compressor, from the receiver, while still maintaining system pressure:
- T = R x P1 – P2 Qr – Qc 7
Use this formula to determine what receiver size to use to supply pressure for a given period of time, not allowing the system to drop below a minimum pressure. The demand of air is greater than the CFM output of the air compressor:
- R = 7 x (Qr – Qc) x T
P1 – P2
Use this formula to determine how long it will take to recharge an air receiver to P1, after demand goes back to being below CFM output of the air compressor:
- T = R x (P2 – P1)
Qr – Qc x 14.7
T = Time in minutes
R = Receiver in cubic feet Qr = CFM removed
Qc = Compressor output in CFM
P1 = Maximum air receiver pressure P2 = Minimum air receiver pressure
14.7 = Atmospheric pressure in PSI (sea level)
CUBIC FT to GALLON CONVERSION: 7.48 gallons in a cubic foot
Why the FS-Connect Piping System?
Do you have problems with the pressure, flow or quality of your air that is affecting your products, increasing your scrap rate due to rejections in quality, efficiency, tooling costs due to increased maintenance or spraying applications like paint jobs?
Then you may want to review your compressed air piping system for a start in enhancing your operation and savings.
What You Need to Consider When Selecting Piping?
- Know your installation & ambient conditions.
Consider the environment the piping system will be installed in. There are many elements that can induce corrosion. Some harsh chemicals or fumes could have an adverse effect on the pipe. Installation conditions could play a role in the effectiveness of your system and life cycle of the pipe.
- Know your flow, the temperature and the pressure min and max requirements.
For safety and overall performance, the flow, the temperature and the pressure should be reviewed and discussed thoroughly before a choice of pipe is made.
- Review the budget and plan for possible expansion in the future.
All pipe options have different price points, different installation requirements and options for future expansion. It’s best to consider all of these factors before choosing the product that will be best for your installation.
The benefit of the FS-Connect Piping System (aluminum) is ease of installation at an extremely competitive cost advantage when compared to traditional piping systems. Our system offers non-plastic fittings for durability and many different mounting brackets to handle all the installation requirements for any location. The FS-Connect Piping is simple, cost-effective and will impact your compressed air system and bottom-line in a positive manner.
As with anything there are always many ways to accomplish the same end result, just with differing energy, thought and cost to get that same end result. If you can have the best quality of air with the least amount of headaches and least amount of waste in terms of production and maintenance for the least cost, wouldn’t you choose that solution? If you are interested in savings and ease of mind the FS-Connect Piping System offers the most flexibility for design and install over all of the other technologies. No sweating is required as with copper piping, no threading, pipe dope and labor intensive cutting and hanging as with the black malleable piping. The copper and black pipe is very heavy and cumbersome to handle making for costly, labor eating installations. The shipping and handling that is involved in the traditional pipe drives the costs even higher. These other technologies also need the special tooling required for the projects. Aside from the installation drawbacks of black pipe and copper pipe one must also be aware of the corrosion that starts attacking these piping materials from the onset. Copper is not nearly as bad from a corrosion point compared to black iron piping, however copper still corrodes over time and does have the high cost factor for installations due to the rising price of copper and labor to sweat.
The Benefits of Using FS-Connect Piping System
The FS-Curtis Aluminum Piping System’s benefits include:
• Energy efficient
• Lower installation costs
• Push-to-connect technology
• Immediate pressurization
• Removable and reusable
• Modular design
• No corrosion
• Leak-free guarantee
• Full bore design
• 1/2" - 6" pipe sizes