1. Main Air Compressor (MAC)

The heart of the plant — compresses atmospheric air before purification and cryogenic separation.

Critical components: Impellers (open and shrouded); pinion shafts and bull gears; tilting-pad journal and thrust bearings; labyrinth and carbon ring seals; inlet guide vanes (IGV) and actuators; diffusers and volutes; intercooler/aftercooler tube bundles; couplings and diaphragm packs.

Applications: Continuous air compression for integrally geared and multistage centrifugal compressors in ASUs and industrial gas plants.

2. Booster Air Compressor (BAC)

Raises the pressure of part of the purified air stream for the expansion turbine and liquid product cycles.

Critical components: Impellers and rotor assemblies; shaft seals and dry gas seals; journal and thrust bearings; gearbox components; coolers and moisture separators.

Applications: High-pressure air supply for liquefaction cycles, pumped-LOX processes and turbine feed.

3. Air Pre-Cooling Unit (DCAC & Chiller)

Cools the compressed air and removes water before purification.

Critical components: Tower packing (random and structured); water distributors and spray nozzles; mist eliminators and demister pads; chilled/cooling water pump spares; refrigeration chiller components.

Applications: Lowering air temperature and moisture load to protect the molecular sieve and improve plant efficiency.

4. Molecular Sieve Purification Unit

Removes moisture, CO₂ and hydrocarbons that would otherwise freeze or create safety risks in the cold box.

Critical components: Molecular sieve and activated alumina adsorbents; switching valves (butterfly, triple-offset, poppet); valve actuators, solenoids and limit switches; regeneration electric heaters; bed support grids, screens and ceramic balls; depressurisation line silencers.

Applications: Continuous adsorption and regeneration cycles for clean, dry air feed to the cryogenic section.

5. Cryogenic Expansion Turbine (Turboexpander)

Produces the refrigeration that keeps the plant cold and enables liquid production.

Critical components: Expander and brake/compressor wheels; rotor shafts and complete rotor assemblies; oil-lubricated, gas or magnetic bearings; variable nozzle assemblies; shaft seals and seal-gas parts; speed and vibration probes.

Applications: Refrigeration generation in low-pressure and high-pressure ASU cycles and liquefier units.

6. Main Heat Exchanger & Cold Box Internals

Handles heat transfer between incoming air and outgoing product streams at cryogenic temperatures.

Critical components: Brazed aluminium heat exchanger (BAHX) headers and nozzles; structured packing and supports; liquid distributors and collectors; sieve trays and tray hardware; reboiler/condenser components; perlite insulation and cold box seals.

Applications: Distillation of air into high-purity oxygen, nitrogen and argon in the HP, LP and argon columns.

7. Cryogenic Pumps (LOX, LIN, LAR)

Transfer liquid products for storage, loading, internal compression and backup systems.

Critical components: Impellers and inducers; mechanical seals and seal faces; cryogenic bearings; shafts, sleeves and wear rings; casings, diffusers and gaskets.

Applications: Product transfer, tanker filling, pumped-liquid compression and cylinder filling stations.

8. Cryogenic Valves

Control and isolate process streams at temperatures as low as −196°C.

Critical components: Plugs, seats and cages; stems and extended bonnets; gland packing and bellows seals; pneumatic actuators and positioners; safety relief valves and rupture discs.

Applications: Flow control, isolation and pressure protection across cold box, storage and transfer systems.

9. Product Compressors (Oxygen & Nitrogen)

Deliver gaseous products at the pressure customers need.

Critical components: Piston rings, rider bands and packing rings; suction/discharge valve assemblies; cylinder liners and crosshead parts; oxygen-compatible seals and gaskets; impellers and seals for centrifugal units.

Applications: Pipeline supply, cylinder filling and high-pressure product delivery. All oxygen-service parts are cleaned for oxygen service.

10. Storage Tanks & Vaporizers

Store liquid product and convert it to gas on demand.

Critical components: Ambient air vaporizer fins and tubes; pressure build-up coils; cryogenic safety valves and regulators; level gauges and transmitters; transfer hoses and couplings.

Applications: Backup supply, customer bulk installations and liquid distribution.

11. Lube Oil & Seal Gas Systems

Protect rotating equipment through lubrication and sealing.

Critical components: Lube oil pumps and motors; duplex filters and elements; oil coolers and heaters; pressure control valves; accumulators and seal gas filters.

Applications: Bearing lubrication and seal protection for compressors, turbines and gearboxes.

12. Instrumentation & Analyzers

Keep the plant safe, efficient and on specification.

Critical components: Oxygen purity and trace analyzers; hydrocarbon and CO₂ analyzers; pressure, temperature and flow transmitters; vibration monitoring probes and proximitors; control valve positioners.

Applications: Product quality monitoring, process safety and machine health monitoring.