• USA - West Texas

    USA - West Texas

    For our client in West Texas we rapidly supplied API682 style Monel seals for hydrofluoric acid duties, rapidly helping restore the equipment to full functional performance.
  • Brazil


    Commissioned to undertake a large dual seal upgrade project for a customer in Brazil, we quickly configured and delivered 53A and 53B pressurised dual seal systems.
  • South Africa

    South Africa

    Asked to manage a reliability programme for a large population of seals, we delivered significant MTBR improvements at our customer's South African petrochemical facility.
  • UK – Aberdeen

    UK – Aberdeen

    For this offshore customer in Aberdeen, we designed, manufactured and delivered engineered high-pressure seals to replace obsolete OEM seals for its main oil line export pumps – all within 48 hours.
  • Middle East – Saudi Arabia

    Middle East – Saudi Arabia

    For this customer in Saudi Arabia, we managed seal repair and a reliability programme at a major petrochemical facility. As well as helping improve reliability, we also reduced the total cost of ownership.
  • Far East

    Far East

    We've won a significant contract in the Far East, giving us responsibility for bearing protection for a major global business in this territory.
  • Italy


    "We were delivered 2 incorrect seals for caustic soda applications that left us in a very uncomfortable situation. We contacted AESSEAL and they guaranteed 2 new seals within the fastest delivery time. AESSEAL are now involved in bids on all key projects in our plant."
  • South Africa

    South Africa

    "We receive 24hr support 365 days a year from AESSEAL. They not only solve our sealing problems through training and expert advice, they also use their extensive pump knowledge to provide significant savings in other areas. In short, they are servicing us to death."

API Plan 53B

Pressurized barrier fluid circulation in outboard seal of dual seal configuration. Circulation is maintained by using pumping ring in running condition and with thermosyphon effect in stand still condition. The pressure is maintained in the seal circuit by a bladder accumulator.   

  1. Keeps barrier fluid and pressurized gas (inert gas) separate by using a bladder.  
  2. Heat is removed from the circulation system by an air-cooled or water-cooled heat exchanger.  
  3. Being a stand-alone system does not rely upon a central pressure source. Hence much more reliable than a Plan 53A.
  4. no case media leakage to atmosphere.
  5. Clean fluid film formation between the inboard seal faces gives better seal life.  
  1. Applications where no leakage to atmosphere can be tolerated e.g. hazardous, toxic, inflammable media.  
  2. For dirty, abrasive or polymerizing products where media is unsuitable as a lubricant for inboard seal faces.
  1. There will always be some leakage of barrier fluid into the product.
  2. Check compatibility of barrier fluid with product.  
  3. Low volume of barrier fluid in system, hence heat dissipation is totally dependent on cooler efficiency.
  4. Always recharge bladder to 0.9 times the working pressure.
  5. Vent the system properly before start up.
  6. Product quality can deteriorate due to barrier fluid contamination.
  7. Can not be used where seal chamber pressure varies. Use Plan 53C for such applications.

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