B12Hx20/1P-SC-S 4x1 1/4"&28U(27)

Part number B12Hx20/1P-SC-S 4x1 1/4"&28U(27) is the SWEP B12 frame carrying 20 plates. The H plate is the obtuse chevron: it gives the most heat transfer per plate and the most pressure drop, so it suits duties where approach temperature matters more than pump head. The /1P-SC fields read as single pass, with 316/316L stainless steel plates and a copper braze. The closing S is the pressure class: 31 bar at 155 C. Connections are listed as 4x1 1/4"&28U(27), in port order. The B12 plate pack measures 287 x 117 mm (11.3 x 4.61 in) on 234 x 63 mm port centres, and by SWEP's published weight formula a 20-plate unit comes to about 2.3 kg (5.1 lb) dry. The frame is published to 16.9 m3/h (74.41 GPM) - a port limit rather than a design flow. If the flow on either side would exceed the published ceiling, the answer is a larger frame, not more plates on this one.