When using OK couplings for shaft connections, advantage is taken of the powerful SKF Oil Injection Method.

When mounting the OK coupling, a thin inner sleeve with a tapered outer diameter slides onto the shaft. A thick outer sleeve with a matching tapered inner surface fits onto the inner sleeve. Oil is then injected between the sleeves. A builtin hydraulic jack drives the outer sleeve up the taper of the inner sleeve. When the outer sleeve has reached its final position an interference fit is createdjust as if the outer sleeve had been heated and shrunk on. But no heat is required, and the coupling can be removed as easily as it was mounted.