Too much expansion/vibration?

shows a situation where an array of pumps is tightly connected to a plate HX and a boiler. (The grayed-out stuff is old work to be removed.) I'm wondering if pump vibration and/or thermal expansion is likely to damage the HX.

Details:
A frame wall (at left) butts into a bedrock wall (background) at right angles. A plate HX is secured to the frame wall by a weldment (not shown). The U-shaped weldment supports the HX at the bottom and sides; the HX is held in the weldment by a web strap. Three pumps will be arrayed side by side (middle pump shown). Pumps will be supported at top and bottom piping by a weldment (not shown) bolted to bedrock. The left two pumps connect to the air seperator (see tee and ell); the right two pumps connect directly to the boiler return via a close ell-and-tee arrangement similar to the one above. The ruler at bottom right represents the left edge of the boiler. The entire arrangement is rather rigid, except that the 26-lb HX can move a tad left-right.

Am I in trouble here? If so, what fix would you recommend? I have no space left-to-right but can work out from the rock wall or down.

Are there approved flexible connections (hose?) which can be used to isolate vibration?