Drilling Safety Valves

Types of Drilling Safety Valves

Drilling safety valves include Kelly Valves, Inside BOP Valves (IBOP Valves), and Retrievable Drop-In Check Valves (RDCV).

Kelly Valve

The Kelly Valve, also called Full Opening Safety Valve (FOSV), can be used as a drill pipe safety valve, Upper Kelly Valve, or Lower Kelly Valve.

  • Upper Kelly – The valve can be used to control blowout pressures by shutting off flow in the drill string at any time
  • Lower Kelly – The valve can stop mud loss when the Kelly is disconnected from the drill string.

Inside BOP (IBOP) Valve

The IBOP, also called Gray Valve or BVR, is a back pressure valve used in the drill string to prevent the well from flowing uncontrollably up the drill string. It is generally used in 2 ways:

  • On the rig floor with a complete IBOP configuration.
  • Below the rig floor without a plug when connected in the drill-string. It can be left in the drill string as long as necessary to re-establish control of the well-pressure balance.

Retrievable Drop-In Check Valves (RDCV)

The RDCV, also called Dart Valve or a Back-Pressure Valve, controls backflow through the drill pipe during a kick or when tripping pipe into the hole against pressure. Check-valve compatibility should be checked with Kelly Cock free passage.

Drilling Safety Valves features as below:

  • Standard – for normal drilling conditions
  • H2S Trim – for low H2S concentrations
  • NACE – For high H2S concentration; fully meets the NACE MR0175.

Kelly Valves

Kelly Valves can be provided as a one or two-piece construction.

Kelly Valves are manufactured from AISI 4140/4145/ 4330 or 17-4 PH alloy steel.

Features include:

  • Simple construction for trouble-free operations and easy servicing sealed lubrication packing complete stainless steel valve parts available for Sour Service
  • Available in 10,000 and 15,000 PSI working pressure operating wrench and thread protectors
  • One-piece construction material 4145 H Mod (120 ksi for standard & H2S Trim versions, 100 ksi for full NACE version)
    • Length to be specified (deep boring limitations)
    • Generally for API connections
  • Two-piece construction material 4330 V Mod (130 ksi for standard & H2S Trim versions, 100 ksi for full NACE version)
    • Generally for high torque connections with larger bore ID passage
    • Longer than standard valve
    • Special design requirements

Two Kelly Valve seat type options:

  • KC2S with PTFE rings inserted in both upper and lower seats and KC4S with metal-to-metal seal. The KC2S PTFE-ring provides good sealing capability, even at low pressures
  • KC4S metal-to-metal seal valve, sealing is performed by controlled elastic deformation of the special plug. This technological choice, combined with enhanced-seat guidance gives excellent sealing characteristics for the life of the valve

Inside BOP (IBOP) Valve

The IBOP valve (BVR) series are linked to passage ID.

Features include:

  • OD sizes from 3-3/8″ to 9-1/2″
  • ID sizes from 1-1/2″ to 2-13/16″
  • Available in 10,000 and 15,000 PSI working pressure.

Retrievable Drop-In Check Valves (RDCV)

Features include:

  • check valve OD sizes from 1-9/32″ to 3-7/64″
  • check valve ID sizes from 3/8″ to 1-11/16″
  • Available in 10,000 and 15,000 PSI working pressure.