• 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 74

Externally pressurized barrier gas through gas control system to a dual seal arrangement. An inert gas is used as a barrier gas.  


  1. Media leakage to atmosphere is eliminated.  
  2. Obtain very high reliability, as solids or other materials, which can lead to premature seal failure cannot enter the seal faces.  
This plan is intended to be used for dual pressurized non-contacting gas seals.  
  1. Used in services which are not hot (within elastomer temperature limit) but which may contain toxic or hazardous material whose leakage to atmosphere can not be tolerated.
  2. In case of solids or other material present in sealing media.
  3. Where process contamination is allowed but process liquid leakage to atmosphere is not allowed.  
  1. Always ensure barrier gas pressure is higher than seal chamber pressure.
  2. Causes media contamination due to high-pressure nitrogen entering the pump.
  3. Back pressure regulator should be set at least 1.7 bar greater than the seal chamber pressure.
  4. Carefully consider the reliability of barrier pressure source, if central pressure issued.
  5. Always check filter for any possible blockage.
  6. Do not use for sticking or polymerizing media.

Do you work with API qualified mechanical seals?


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