Plate Pack Expansion

Measure the clear length of carrying bar between the closed pack and the support column, and compare it with the space the extra plates would take up. The serial number lets us look up the maximum plate count the frame was built for. Send the current plate count with that measurement and we can tell you how far the pack can grow.

They will when ordered against the serial number, since that fixes the model, material, pattern and gasket attachment. What differs is gasket age. Where the existing gaskets have seen years of cycling and cleaning, an expansion is a sensible moment to regasket the whole pack, so every plate seals at the same compression.

Wherever the rating says they belong, which is not always the end of the pack. Mixed-pattern packs and multi-pass arrangements need new plates placed so the pass and pattern sequence stays correct. We give you the revised plate arrangement with the rating, listing position, pattern and orientation for each plate, plus the new tightening dimension that goes with it.

Often less than the plate count suggests. Adding plates lowers velocity in every channel, which reduces the heat transfer coefficient, so the gain in duty usually trails the gain in area. The rating shows the real figure along with the new pressure drop, which falls for the same flow and may let you raise the flow instead.

Only if the existing bolts are too short to close the longer pack with full thread engagement, or if they are galled or stretched. Bolt length is fixed when the frame is built, so a frame specified with expansion room normally came with bolts to suit. Measure the thread left past the nuts now and send it with the plate count.

When the ports, rather than the surface, are limiting the duty. Once port velocity is high, more plates add area but the flow cannot rise to use it, and pressure drop through the connections climbs. At that point a larger frame or a second unit in parallel is the better buy, and the existing unit can often move to a smaller duty elsewhere in the plant.