The importance of dry and clean air
When atmospheric air goes through a compressor, the air volume is reduced but the air still contains the same amount of impurities and water as the original air volume.

The ambient air in the engine room onboard a ship may contain up to 1 mg/m3 of oil, and the air also contains water and particles. To avoid possible damage to the compressor and equipment using compressed air and make sure the air quality satisfies the quality standards required, proper drying and filtration of the compressed air is essential.

TMC offers complete compressed air systems including dryers and filters to achieve the highest air quality.

p 20 damages

Typical areas that will be affected by bad air quality:

  • Air receivers/piping systems
  • Air motors/bearings
  • Tank sounding systems
  • Pneumatic valves
  • Electro-pneumatic steering systems
  • Pneumatic control systems
  • Process equipment


TMC always specifies dryer capacity at 45°C - do you know why?

The inlet and ambient temperature is crucial for a dryer’s performance. Dryer capacity decreases dramatically with higher inlet/ambient temperatures, and therefore dryer capacity calculations must take temperature into account.
Very often, dryer capacities are specified based on an inlet/ambient temperature of 25°C. It is important to note that with an inlet/ambient temperature of 45°C - which is the normal temperature in a ship’s engine room - the dryer’s capacity will be only half of what was specified at 25°C. That’s why TMC always specifies all dryer capacities based on inlet/ambient temperature of 45°C at 7 bar.


Proper filtration is the only way to obtain oil-free air

A compressor installed on board a ship will compress the ambient air, which normally contains various impurities and up to 1 mg/m3 of oil.
Due to the high oil content in the suction air, proper filtration should always be installed downstream to ensure the quality of the air.
It’s a widespread belief that an oil-free compressor (a compressor with no oil in its internal system) produces oil-free air. This is not correct. The impurities from the ambient air will not disappear when it goes through the oil-free compressor.
An oil-lubricated compressor with proper filtration can easily achieve oil-free air of the highest purity class under ISO 8573.1. An oil-free compressor also needs proper filtration to achieve this.
In air systems set up to achieve the highest air quality, oil-lubricated compressors, as supplied by TMC, have many advantages.

To determine the total economy of an oil-free compressor versus an oil-lubricated compressor,  consider the following:

Investment costs
Considerably lower for an oil-lubricated compressor

Overhaul intervals
Considerably longer for an oil-lubricated compressor

Service
Considerably simpler and easier for an oil-lubricated compressor

Reliability
The reliability of oil-lubricated TMC compressors is well established. Reliability is particularly impressive for the high ambient temperatures in which an oil-free compressor operates.


p 20 air system

Example of  compressor, dryer, filters and receiver
incorporated into an optimal TMC air system.

P.O. Box 3 Furuset,
N-1001 Oslo, Norway
Tel: +47 22 91 85 00
Fax: +47 22 91 84 93
24 hour emergency phone: +47 99 21 70 20
mail@tmc.no