Abstract: An orifice plate mounting assembly includes a manifold having an interior cavity defining an elongated slot and fluid communication therewith and a pair of exterior vertical guide surfaces bracketing a recessed substantially planar surface surrounding the elongated slot. A pair of clamping members each having a clamp body, a clamping arm extending horizontally outwardly from the clamp body and defining substantially planar contact surfaces, and hinge elements are provided to horizontally position the planar contact surface of each clamping arm in planar contact with the respective portion of the planar orifice plate laterally of the linear array of orifices. Suitable securing elements bridge the manifold assembly in each clamp body to cause each planar contact surface to exert a clamping force against the orifice plate so as to, in turn, exert a clamping force between the planar orifice plate and the recessed planar surface.