Aavolyn is a Manufacturer and Supplier of
High Quality Compressor Replacement Parts
Printable PagePrintable PageEmail This PageEmail This Page
Ava5015 Filled PTFE Material | Aavolyn Technical Support | Routine Maintenance | Aavolyn TY655 Water Cooled Packing Assembly | Pressure Balanced Piston Rings | Rider Ring Design | Aavolyn TY260/261 PBU Design | Aavolyn AVA5015 Stats | Oxygen Service Worldwide

SPECIALTY GAS COMPRESSOR SERVICE

AVA5014 Filled PTFE  Oxygen Service
[click to enlarge]
AVA5014 Filled PTFE Oxygen Service
 

AVA5015 FILLED PTFE MATERIAL

50 years plus and still going strong….. For over 50 years AVA5015 has been the standard material for use in OXYGEN sealing applications. Extensive testing and development by PRAXAIR and AAVOLYN engineers produced a material which provided three to five times the wear life over all other materials in oxygen service. This patented filled PTFE has no equals when used in oxygen compressors for sealing rings. Because of the excellent frictional properties of AVA5015, wear on compressor cylinders and piston rods have been eliminated. Cost savings in reducing down time for ring replacement and elimination of cylinder and piston rod wear are significant. The expense of just one shutdown for ring replacement or cylinder re-boring more than justifies the use of AVA5015 materials in all oxygen service applications.

SAFETY CONSIDERATIONS
  • Potential of explosion and fire
  • Non-sparking materials used
  • Thorough cleaning procedures

System cleanliness is critical in oxygen components and systems because contaminants may cause functional anomalies or ignition. Insufficient cleanliness of components used in oxygen systems can result in the ignition of contaminants or components by a variety of mechanisms such as high velocity particle impact, adai babtic compression, mechanical impact, or friction. Cleaning must ensure the removal of contaminants which could potentially cause mechanical malfunctions, system failures, fires or explosions. Oxygen compressors require complete removal of contaminants such as hydro-carbon greases, oils, thread lubricants, dirt, filings, or any other foreign material from areas coming in contact with the oxygen gas or liquid. Strict adherence to approved cleaning procedures at all times ensures the safety of the personnel in the area of the compressor and limiting of damages from oxygen fires. All products furnished by AAVOLYN oxygen service are subject to their approved cleaning procedures, followed by Black Light inspection prior to and after assembly. AAVOLYN CORP is the largest supplier of oxygen seals and rings in the world. We are proud of our perfect record of no contaminants of cleaned for oxygen products.

back to top
 Oxygen Service Plant
[click to enlarge]
Oxygen Service Plant
Aavolyn Sales Booth
[click to enlarge]
Aavolyn Sales Booth
 

AAVOLYN TECHNICAL SUPPORT

AAVOLYN engineers maintain a complete record of each OXYGEN compressor for which we provide replacement parts and service. A file is developed for each unit including piston drawing, parts lists and a history of machine activity. Customers are alerted of anticipated parts replacement cycles as well as verifying ring dimensions and piston configurations. Routine contacts occur between maintenance personnel and Aavolyn’s sales support group to confirm technical information before proceeding with parts requisitions or scheduling parts replacement. As part of AAVOLYN customer service, next day emergency delivery is available for most piston rings, rod packing and oil wiper sets. Maximum stock levels of AVA5015 billets allow for the routine customer emergency requirements. The availability of AAVOLYN engineers to assist in answering technical questions and making recommendations provides an added level of security to maintenance technicians.

back to top
 Aavolyn Packing Kits
[click to enlarge]
Aavolyn Packing Kits
Aavolyn Oxygen Routine Maintenance
[click to enlarge]
Aavolyn Oxygen Routine Maintenance
 

ROUTINE MAINTENANCE

Frequency and content of maintenance work is based on the compressor builder’s recommendations along with operator’s experience. The strict upkeep of regular and detailed analysis of compressor running data is crucial in ensuring safe operation. A number of factors apply to the period between major overhauls; compressor builder’s recommendations, number of hours run, number of starts since last overhaul, and previous operating history. The maintenance schedule will define the maxi-mum time between maintenance shutdowns and indicate the operations to be performed for over-haul, inspection and checking of the following: cylinder valves, lanterns and gaskets, oil scrapers and piston rod surface, clearances of bearings, piston clearances, piston rings, rider rings and packing, tightness of connection rod bolts, tightness of piston nuts and crankshaft deflection. Prior to performing any maintenance work on an oxygen compressor provisions are to be taken to ensure that the equipment is purged and positively isolated. Safe working conditions around the compressor dictate that oxygen concentration be between 19.5% and 23.5%. Leaking flanges or defective seal systems can create the occurrence of either a oxygen enrichment or oxygen deficiency situation. OXYGEN PURITY 99.5%

back to top
  
Aavolyn Type 655 Fab Cup
[click to enlarge]
Aavolyn Type 655 Fab Cup
 

AAVOLYN TY655 WATER COOLED PACKING ASSEMBLY

AAVOLYN engineers developed the fabricated cup design as the most efficient type of internal coolant design. The TYPE655 consists of a fabricated coolant cup. The AAVOLYN design brings the coolant areas close to the bore of the case to allow maximum heat transfer. The size of the coolant areas are enlarged to provide a large surface for heat transfer. This design is used in all gas services and all discharge pressures.

One of the value added features of the TYPE655 water cooled packing assembly is that the “O” ring sealing the coolant flow from cup to cup does not go around the rod. Hence, the rod does not have to be removed to replace them resulting in a major time saver. Bronze packing cases are recommended in oxygen service to minimize the possibility of sparking and frictional heat.

back to top
 Aavolyn Products Table
[click to enlarge]
Aavolyn Products Table
  

PRESSURE BALANCED PISTON RINGS

The common features of a piston ring, regardless of style, consist of a ring which conforms to the diameter of the cylinder and allows clearance under and alongside of the ring to allow it to move freely in the groove in which it is contained. The side clearance is based on the ring material and temperature at operating conditions. A space is allowed under the ring to provide room for the sealed substance to provide pressure against the I.D. of the ring creating a seal on the O.D. against the cylinder. A gap is provided in the ring to provide room for expansion and also a slight path for leakage. Ideally, any seal should be designed to apply the least amount of force at the sealing surface, just enough to seal without adding additional force which produces frictional heat and reduced seal life. Aavolyn engineers recommend TYPE480 two piece pressure balanced ring design for pressures over 300 PSI.

The piston rings displayed show a cross section of the TYPE480. From this view you can see the OD groove and drilled holes which allow some of the gas to travel to the sealing side of the ring. This gas causes a downward force in the groove. The result-ant gas pressure against the sealing surface is reduced, thereby minimizing the forces which cause frictional heat. The two piece style also improves the sealing performance by allowing the piston ring to contact the cylinder through 360 degrees and maintain at contact at start-up. The proper design for each sealing application allows for maximum performance and ring life.

back to top
 Aavolyn Piston Rings
[click to enlarge]
Aavolyn Piston Rings
  

RIDER RING DESIGN

The rider ring functions as a projection against the piston rubbing against the cylinder wall in a metal to metal contact. The proper design of rider rings for use in reciprocating compressor applications can increase the life of the installation and limit cylinder wall damage. The width of each rider ring is calculated to support the piston and rod weight for 12,000 to 16,000 hours of operation. The projection of the ring over the piston also contributes to ring performance. Aavolyn engineers recommend approximately .125” on a side on average between the piston and cylinder to provide satisfactory ring life.

The TYPE470 rider has extensive diagonal grooving arrangements across the face of the ring to ensure that gases pass over the rider ring. These grooves are parallel to create some turning force. Because of the large surface area of the rider ring, any sealing can cause significant frictional heat. It is important that the rider does not act as a seal.

back to top
 Aavolyn Rider Rings
[click to enlarge]
Aavolyn Rider Rings
Aavolyn Type 260/261 PPBU Design
[click to enlarge]
Aavolyn Type 260/261 PPBU Design
 

AAVOLYN TY260/261 PBU DESIGN

The AVA-PBU pressure balanced unitized design is the latest concept in shaft seals. The PBU was developed to ex-tend packing life in conventional applications. In addition to extensive use in oxygen compressors, it can be found in services from non-lube air to 50,000 PSI compressors handling polyethylene. Each ring operates on the principle of balancing the pressures around the seal to minimize the downward force of the piston rod. Frictional forces are reduced considerably. In oxygen service where AVA5015 PBU’S are utilized, there is less chance that the PV limit (temperature/pressure limit) of the PTFE will be exceeded because of reduced frictional heat.

back to top
 Aavolyn Type 260/261 PPBU Design
[click to enlarge]
Aavolyn Type 260/261 PPBU Design
Aavolyn AVA 5015 PTFE
[click to enlarge]
Aavolyn AVA 5015 PTFE
 

AAVOLYN AVA5015 STATS

PHYSICAL PROPERTIES
PropertyUnitsASTM TestAVA5015
Specific GravityGr/cmD14572.482
TensilePSID14572460
Elongation%D1457272
Hardness  58
   Shore “D”
back to top
 Aavolyn AVA 5015 Specifications
[click to enlarge]
Aavolyn AVA 5015 Specifications
Oxygen Service Worldwide
[click to enlarge]
Oxygen Service Worldwide
 

OXYGEN SERVICE WORLDWIDE

Oxygen compressors are used worldwide in a variety of industries, including refining, chemical, glass, metal fabrication and production, petrochemical, pulp and paper, steel, and technical gases to name a few. Oxygen (O2) constitutes approximately 21% of the air,. Oxygen is produced by air separation processes that use either cryogenic liquefaction and distillation of vacuum swing adsorption (VSA) separation. Stored and shipped oxygen can be in the form of either gas or a cryogenic liquid. The principal uses of oxygen stem from its strong oxidizing and life-sustaining properties. Oxygen is used in the pulp and paper industry for a variety of applications, including pulp bleaching, black liquor oxidation, and lime kiln enrichment. It is used in medicine for therapeutic purposes and in the metals industry for steelmaking and metal-cutting applications. In the chemical and petroleum industries, oxygen is used in the production of a variety of fuels and chemicals. In the glass industry, oxygen/fuel combustion is used to reduce particulate and NOx emission in melting operations. Oxygen is also used for gasification applications for producing synthesis gas to make chemicals, fuels, electricity, hydrogen or steam.

Aavolyn is a trusted supplier to numerous Original Equipment Manufacturers worldwide. Aavolyn products are proudly manufactured by experienced machinists in our Millville, New Jersey location.

back to top
 Oxygen Service Plant
[click to enlarge]
Oxygen Service Plant