Underbalanced Drilling Hoses

API Spec. 7K FSL 1

Rotary hoses connecting to the top drive with special lining for underbalanced air, foam or mist drilling.

Underbalanced Hose Construction


Internal diameter 2” to 4"
Bore type full flow, smooth bore
Liner type H2S resistant PA
Design pressure up to 7,500 psi
Coupling bonded
Operating temperature -20° C to +82° C (-4° F to 180° F)
Max. available length 60 m (200ft)
For further technical details download the datasheet

Features & Benefits

  • Used for gas, air and foam drilling
  • Further constructions are available on request
  • Not suitable for operations where the hoses are likely to be exposed to well bore effluents. For such applications, see managed pressure drilling hoses.