Pneumatic Quarter Turn Actuator (Type PSA)

Within its product range, BESI Marine System GmbH supplies single and double acting pneumatic quarter turn actuators of type PSA. The force transmission is via rack and pinion. Both, single and double acting actuators come along ready assembled with a 5/2 way solenoid valve. To meet marine conditions the actuators are specially coated. Torque levels range upto 7800 NM.


BESI PSA actuators may be installed in almost any location such as dry spaces, submerged on deck as well as in hazadous areas. For operation all pneumatic type PSA actuators only need one pipe for air supply.

Position Indication

PSA actuators are equipped with either compact O/C limit switches. These can be supplied with IP67 protection class or as Eex proof version. The remote position indication can be visualized and processed in decentralised and compact units or integrated into BESI RCV remote control and automation system.

Emergency Operation

Every PSA actuator is equipped with a quick connection coupling for emergency operation via portable pneumatic compressor (PEC). Upon request, the actuator may also be combined with a declutchable gear for manual operation.


  • At customers´ choise, BESI PSA quarter turn actuators are available in single or double acting execution.
  • Standard air suppliy pressure required 8 bar. However actuators suitable for other air pressures´ are available upon request
  • As a standard actuators come with protection class IP67. However protection class IP68 is available upon request.
  • ESG limit switch box may be delivered with poly carbonate housing or with aluminium housing. Alternatively inductive proximity switches are also part of the supply range.
  • BESI type PSA actuators may be integrated into BESI TMS<
  • Surface protection is in standard BESI blue, but at customers´choise may be changed into other colours or paints.


Double Acting Actuators
Model Torque at 8 bar air supply
PSA 32 10
PSA 42 17,3
PSA 50 24,6
PSA 63 44
PSA 75 93,6
PSA 85 142,4
PSA 100 221,8
PSA 115 366
PSA 125 481,4
PSA 145 693,6
PSA 160 946,8
PSA 180 1277,3
PSA 200 1775
PSA 240 2980,4
PSA 270 4313,6
PSA 330 7811,9

Single acting actuators are available from 8,4 up to 6081,80 NM

ISO 9001 certified

BESI Marine Systems GmbH
Vorweide 4
D-28259 Bremen