What is an air booster?
Air boosters take pre-compressed air from an existing network (your plant air system) or from a low pressure compressor and increase it to the required higher pressure. A Hycomp Oil Free Air Booster is a specially designed reciprocating compressor that accepts elevated inlet pressures, usually below 150 psig, and boosts that pressure up as far as 1500 psig.
When and where is an air booster applied?
When plant pressure isn’t enough, an air booster is often the best solution. Standard compressed air systems in industrial facilities are typically designed for pressures of 80 to 130 psig. When higher pressures are required, it is very effective to use a portion of your plant air and apply an air booster to obtain the desired higher pressure. Other methods of acquiring higher pressure air – such as stand-alone air compressors, air amplifiers, and increasing the pressure of the entire plant – are more costly and less efficient. It simply takes more power to start from a standstill, while an air booster gets a running start because it receives pre-compressed air.
How does an air booster work?
Think of an air booster as a second or third stage to your existing air compressor. An air booster connects into your plant air system via a receiver tank, piping and a discharge tank. These tanks are used to dampen pulsation created by the reciprocating movement of the booster and provide a small amount of storage capacity.
Hycomp Oil Free Air Boosters are built using a reciprocating design. However, there are five major factors concerning engineering and construction that provide a good inside look at how a Hycomp air booster works and why our air boosters are higher quality than the competition.
(1) Oil Free – Every booster and compressor we manufacture is oil free. Your process remains clean, and your air stream pure because oil never enters the compression cylinder.
(2) Cast Iron & Steel Construction – Our major castings are iron or steel. Unlike aluminum these materials hold their shape and don’t warp at elevated temperatures. They provide additional vibration dampening and allow Hycomp boosters to operate for years without major component replacement.
(3) Plenum Intake – Our unique “Plenum Intake” design receives air below the compression cylinder through the plenum chamber. This innovative style of intake and compression provides three major benefits: (i) cooling effect on rings and packings; (ii) balanced piston rod loads; and (iii) internal air reservoir.
(4) Oil Isolation – Our distance piece and piston rod oil scrapers keep the oil isolated to the crosshead cylinder and crankcase and away from your compression. Oil scrapers remove oil from the piston rod while the open distance piece protects against oil vapor entering the air stream.
(5) Pressure Oil Lubricated – Our crankcase is pressurized to provide generous lubrication to all moving parts. Unlike splash lubrication that spreads oil sporadically, the oil in our crankcase is liberally delivered with pinpoint accuracy. The Hycomp oil lubricated bottom end decreases running temperatures, allows for higher discharge pressures, and provides longevity.
We believe there are no small details. From our heavy cast iron cylinders to our 14 gauge powder coated steel beltguards, we cut no corners. The following are four examples of superior Hycomp components.
- Valves – Hycomp valve bodies are made from only the highest quality 400 series stainless steels, which have been heat treated for hardness and toughness. Our valve plates are machined precipitation hardenable stainless steel or crystallized PEEK, depending upon the pressures and temperatures of the service. By design our valve plates are frictionless guided so there is no valve cage wear. The port design of our valves has been refined to provide improved flow efficiency, saving power, and decreasing valve impact forces. Our larger valves are dampened, providing additional wear reduction without sacrificing flow efficiency. All of our valves are removable with minimal effort and rebuildable on site.
- Piston Rings – Our standard air booster piston ring is a PTFE based material with bronze, molybdenum disulfide, and several proprietary fillers. The bronze provides excellent heat conductance and wear resistance, while the PTFE and moly are natural oil-free lubricants. Hycomp’s proprietary fillers add to the lubricity of the ring while stabilizing the other fillers against oxidation. Our angle cut design allows for flexing of the ring end to seal the gap better than butt cut designs, while retaining its strength versus step cut designs. In smaller cylinders where gap leakage becomes significant, we use a 2-piece “L” style design that removes the end gap by using an inner and outer ring for sealing.
- Rod Packing – Piston rod packings prevent air leakage out of the booster, while providing pressure on the underside of the pistons to balance the rod loads. Hycomp’s tangentially cut segmented packings are free floating and self-adjusting for long wear life. The design inherently continues to seal as the packing wears. A pair of packings are pinned together at the proper rotational offset to ensure that the leakpath created by the cuts are sealed. Unlike chevron type packings, our segmented packings do not need constant adjustment to ensure a tight seal. While they are more difficult to manufacture than a simple chevron shape, our customers agree they are worth the trouble-free service they provide.
- Piston Rod Oil Scrapers – Oil scrapers perform the essential service of preventing oil from migrating out of the crankcase and into the air stream. Combined with Hycomp’s open distance piece design – which allows residual oil vapor to escape the machine – our piston rod oil scrapers provide a leak free seal on our pressure oil lubricated bottom end. Our segmentally cut scrapers are based on a similar principal to our gas packings, as they continue to adjust as they wear. The sharp edges machined into the brass scraper remove oil from the rods, while the liberal porting allows the oil to flow back into the crankcase. As they are a softer material than the piston rod, the brass scraper wears while the rod does not.
Why choose an air booster?
- Cost – When combined with your plant air, a Hycomp Air Booster pays for itself in short order. Because an air booster starts with an elevated inlet pressure, you are using a smaller machine to meet your requirements. Hycomp Air Boosters use less horsepower and still provide higher pressures. It takes more power to begin compression from ambient air. For example: when you are compressing ambient air from 0 psig to 600 psig the compression ratio is 41.8:1. However, when compressing air from 100 psig to 600 psig the compression ratio is only 5.4:1. A smaller compression ratio equates to smaller equipment, which makes your system less expensive to purchase, install, operate, and maintain.
- Continuous Duty – Hycomp Air Boosters do not experience air loss. What you put in is what you get out. Unlike pneumatically driven air amplifiers that use up to 60% of your air flow to power the machine, our air boosters are electrically driven. Traditionally continuous duty is defined as when unload time is less than load time per hour. Our compressors are engineered for slower running speeds to handle 60 minutes per hour, 24 hours a day and 365 days a year of continuous operation.
- Completely Modular – We offer 2 cooling methods, 9 block sizes, 6 packing arrangements and 20 cylinder sizes. The modular nature of Hycomp Compressors and Boosters allows us to meet your needs rather than you changing to meet ours. You are not locked into specific suction or discharge pressures because our modular style of construction creates nearly endless compression possibilities, which equates to custom built air boosters without the custom price.
Bottom Line: When your plant air pressure isn’t enough, an air booster is the most efficient and cost effective choice for worry-free and oil-free continuous duty high pressure air.