A machining system with a configuration in which working machines, including a machine tool, are configured to be disposed in a line, and in which multiple working machines perform operations on one work in order, is provided. The machining system includes: a base; and multiple working machine modules which are mounted on the base and are arranged in an arrangement direction, and has a configuration in which each of the multiple working machine modules is capable of being drawn out from the base along a track extending in an intersecting direction intersecting with the arrangement direction.

A counterweight mechanism for a swivel arrangement includes first and second counterweights each including a seat, an axle, and two cylinders. The swivel arrangement has one end adjacent to the axle. The axle is rotatably, partially disposed in the seat. Each cylinder has a first end pivotably secured to a position proximate to the axle and a second end pivotably secured to the seat.