Turner, 24, a 2014 third-round pick of the Miami Dolphins, started 14 games the last two seasons, primarily at guard. He was cut by the Dolphins after allowing three sacks and two quarterback hits Sunday when pressed into emergency service at left tackle.
Bringing in Turner comes one day after the Ravens signed guard Vladimir Ducasse. Baltimore now has 10 offensive linemen on the roster.
The Ravens were without three starting offensive linemen in Wednesday's practice -- tackles Ronnie Stanley and Rick Wagner as well as Pro Bowl guard Marshal Yanda -- and these additions seem like the team is preparing to not have at least two of them Sunday against the New York Giants.
Baltimore could be looking at starting Alex Lewis at left tackle, John Urschel at left guard, Jeremy Zuttah at center, Ryan Jensen at right guard and either Yanda or James Hurst at right tackle. That would leave Turner and Ducasse as backup interior offensive linemen.
The Ravens cut linebacker Chris Carter to make room for Turner. Carter's primary role was on special teams, which has struggled this season. Baltimore ranks as the third-worst punt coverage team, giving up an average of 18.9 yards.