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  • Run and set in a wide range of downhole conditions
  • Eliminate no-go shoulder swaging with large pressure bearing locking dogs
  • Smooth bore through the lock protects the operating mechanism from corrosion or sticking by foreign materials

  • High-pressure/high-temperature (HP/HT) applications
  • Subsea tubing hanger operations



Ensure reliable locking of your flow control systems with locking systems from Baker Hughes.


Locking designs from top to bottom

Our Sur-Set™ locking mandrels, which include the models AF™, HF™, and extreme type lock assemblies, are top no-go style locks. With a no-go shoulder located just below the locking dogs, these locks will land and lock flow control devices in the corresponding top no-go seating nipples.

The Baker Hughes Models AR™, HR™, and Extreme R™ lock assemblies are bottom no-go style locks. These locks have a no-go shoulder either on the packing mandrel or, in cases where packing is not required, on the flow control accessory. These locks will land and lock flow control devices only in the Models AR, HR, and extreme R bottom no-go seating nipples.

Work with our application specialists to select a locking system that is compatible with the size and model designation (based on designed pressure rating) of your selected seating nipple.

The selective Sur-Set™ line uses all the features from the standard top and bottom no-go Sur-Set locking mandrels, but with the added benefit of maintaining one sealbore diameter for the entire production string.

For your HP/HT applications, the Extreme™ Sur-Set non-elastomeric flow control locking system has an extensive history of success in HP/HT wells.

We also offer a proven short Sur-Set locking mandrel, which have a reduced linear length that prevents damage to the flow control device when moving wellheads on or off.


Designed for durability

Each locking system is designed to run and set reliably in your most extreme downhole conditions. The system’s simple and rugged construction is vibration proof and is suitable for H2S/CO2 service at 300°F (148.8°C) with standard seals.

Both the lock and running tool are compatible with normal wireline equipment and procedures. The running tool also gives a positive indication that the lock is set in the nipple and that the locking operation is complete.

Contact us today to learn how our locking systems can optimize the operation of your flow control systems.

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