» TCM Air-Cell™

TCM Air-Cell™

Transformer air cellTCM Customer Service  

Built specifically for the electrical transformer industry

About the TCM Air-Cell
The Transformer Conservator Membrane (TCM) Air-Cell flexible separator is specifically engineered for the electrical transformer industry.  SEI designs TCM Air-Cells to be used inside cylindrical, elliptical, octagonal or rectangular-shaped conservator tanks.  The TCM Air-Cell floats in oil inside the conservator and expands/contracts by breathing through a flange placed in a customer-specified location, thus allowing the TCM Air-Cell to compensate for oil displacement due to temperature variations in the transformer.
The TCM Air-cell also acts as a barrier to separate undesirable elements in the atmosphere, such as water vapor, nitrogen, ozone and oxygen, from transformer oil within a conservator.  This barrier also reduces condensation and oxidation inside the transformer and suppresses gas bubble formation in the transformer oil. 
SEI custom fabricates each TCM Air-Cell to fit a client's specific conservator tank.  Fitted inside the conservator tank, the Air-Cell isolates insulating oil from the atmosphere which prevents contamination from gas or moisture due to oxidation or hydrolysis. 
SEI specializes in quick delivery for custom TCM Air-Cells to meet the demands of field service operators.  When required, SEI can engineer and manufacture a new Air-Cell in as little as 24 hours from an approved drawing or damaged tank.  All SEI TCM Air Cells enable sealed conservator insulating liquid preservation systems to meet IEEE Std C57.12.00-2010 6.6.2.
Comparison Chart

Fabric Conservator Air-Cell

Oil-Filled, Inert Gas Preservation

Lower annual maintenance
System must be monitored more closely.
Lower operational costs.
System must be topped up each year.
More reliable for remote or unmanned locations.
If no monitoring, must be manually inspected.
Better operational temperature ranges
More temperature sensitive
Fungicide can be added
No need for fungicide
More labor intensive to install
Usually comes fully assembled
Less likelihood of oil contamination
Higher likelihood of oil contamination




SEI Industries TCM Air-Cell
Custom Construction
TCM Air-Cells are constructed from Temp-Shield™ 30 oz. (1017 g) urethane elastomer-coated nylon fabric that has been specifically designed to be compatible with transformer oils, silicon fluids and bio-degradable transformer oils.  The fabric is highly abrasion-resistant and is extremely flexible, ensuring a long-term airtight barrier. 
Temp-Shield™ has a high temperature resistance (up to 130 degrees Celsius) and can be used in extreme low temperature settings up to -50 degrees Celsius.  Temp-Shield's nylon substrate also stretches, offering protection against over pressurization or vacuum during installation.
  • SEI offers a selection of standard sizes to meet a variety of conservator oil volume levels.  SEI can also design and manufacture TCM Air-Cells to exact conservator tank size specifications and oil volume levels.
  • All seams are radio frequency welded and seam sealed then tested to insure seam strength and a long-term airtight barrier.
  • A flange is inserted into each TCM Air-Cell.  The flange provides a point of entry allowing the TCM to act as a breather.  Flanges can be located anywhere on the Air-Cell to match conservator tank design and SEI offers a variety of standard aluminum flanges.
  • Since the insulating oil is completely isolated from the surrounding atmosphere, there is no possibility of oxygen or moisture getting inside the TCM.
  • The TCM maintains constant pressure on the surface of the oil which, in turn, prevents the oil from becoming supersaturated and forming bubbles.  As a result, high dielectric strength can be maintained.
  • Each TCM Air-Cell comes complete with hoops or handles that are used during deployment.  These handles are also used to secure the Air-Cell to the conservator tank.  SEI will place the handles according to the conservator tank design.
  • Reinforced patches are placed around the flange, handles and at the point of contact with the level indicator to provide extra wear protection.
  • Each TCM Air-Cell is individually marked for identification to enable easy inventory tracking.
  • SEI can design and fabricate custom flanges to meet specific conservator tank designs.
  • SEI can offer alternate handles or securing tabs to meet bar or hook conservator tank attachment points.  

BATT wins third award for innovative technology

BC Export Award

Category Numbers
  • Dun & Bradstreet (DUNS): 24-313-6116
  • Cage Code: 0CAE9
  • Procurement Business No (PBN): 104774930 PG0001
  • United Nations: 3226

Product Information

 TCM Brochure   
TCM Operations Manual