The visitors made it six wins from eight matches, with one draw, and they are on target for the playoffs after pulling away in the second half against the Force.
The Force have won just one match from nine outings and are well out of contention as pressure mounts on coach Michael Foley.
The game was in the balance when the Bulls led 18-13 at the break, with the Pretoria-based team running in the first two tries of the game through Hanro Liebenberg and Jan Serfontein in the opening 20 minutes.
The Force struck back through skipper Matt Hodgson in the 26th minute.
However, the Bulls put the margin beyond a converted try after the resumption, with a penalty to Francois Brummer in the 49th minute.
They then broke the game open with three tries in 15 minutes as the Force wilted and suddenly found themselves down 42-13.
A second try to Serfontein as he broke through the defence in the 54th minute gave the Bulls a commanding lead.
Five minutes later, skipper Adriaan Strauss capitalised after a line-out win to score.
The Force were on their knees and Strauss finished them off by driving over the line for his second try in the 67th minute.
The home side scored a consolation try after the final hooter through Kyle Godwin.
Strauss was delighted with the performance ahead of a trip to Canberra to face the Brumbies.
“Very happy with the performance,” he said.
“They stuck to the game plan until the end. The forwards and the backs did quite well tonight and worked hard for each other.”
Force skipper Matt Hodgson said his side were competitive for large parts of the match.
“We were in it for a lot of the game, but weren't tough enough,” he said.
“They got some momentum, got back-to-back tries and they are hard to stop.” – AFP
Original source: Bulls ease past Western Force