ESP bag seals (protector bags) are the positive-seal element inside an ESP motor protector. Positioned between the well fluid and the motor, the elastomer bag physically separates the two fluids, equalises downhole pressure, and absorbs the volume change as the motor oil expands and contracts with temperature. Bag-type chambers are especially effective in highly deviated wells and wherever well-fluid and motor-oil gravities are similar — but once a bag is breached, well fluid reaches the motor quickly, so compound selection is critical.
Our 540-series ESP bag seals are moulded in AFLAS (FEPM / TFE-P), giving excellent resistance to sulphuric acid and oil together with excellent high-temperature performance. AFLAS bags also resist steam, hydrogen sulfide (H₂S), CO₂ and amine-based corrosion inhibitors, with continuous temperature capability up to 250 °C (482 °F). Other compounds — HNBR, FKM and FFKM — are available to match your well chemistry.
Because the bag is the only barrier between produced fluid and the motor, compound choice decides run life. We mould 540-series bags in AFLAS (FEPM/TFE-P) as standard, and in HNBR, FKM or FFKM where well chemistry or temperature calls for it. Every bag is moulded, trimmed and inspected in-house so wall thickness stays uniform through the rolling convolutions — the area where thin spots turn into early failures.
Key Features
- Series: 540 (5.13 in / 130 mm housing OD)
- Compounds: AFLAS (FEPM) standard; HNBR, FKM, FFKM on request
- Temperature: up to 250 °C (AFLAS)
- Resists: oil, steam, sulphuric acid, H₂S, CO₂, amines
Typical Applications
- ESP motor protectors in deviated and horizontal wells, where bag chambers outperform labyrinth chambers
- High-GOR wells and wells with gas-handling equipment, where pressure cycling is severe
- Hot wells with continuous bottom-hole temperature approaching 250 °C
- Sour wells containing H2S, CO2 and amine-based corrosion inhibitors
- Planned workovers and protector rebuilds on 5.13 in / 130 mm ESP housings
Custom Options & Ordering
- Housing size: 540 series (5.13 in / 130 mm OD)
- Compounds: AFLAS (FEPM), HNBR, FKM, FFKM
- Supplied as bare bags or as part of a complete protector rebuild
- Drawing- or sample-based production for non-standard lengths and end fittings
Request a Quote
Tell us your medium, working temperature, pressure and dimensions and we will recommend the compound and geometry for your duty. Reach our engineering team at sales@aobo.biz or +86-573-87855272, or use our contact page.