A tractor beam is installed to a gun mount in the same 
manner as any other weapon. To use a tractor beam, 
cycle through your guns using [g] to select the 
tractor beam alone. Target and lock onto your object 
of interest, use [F9] to match speed, [TAB] to after 
burn close to the object and fire the tractor beam 
using [SPACE BAR] to capture the object.

[g] select tractor beam
[F9] match speed
[TAB] afterburn close to the object
[SPACE BAR] capture the object