SWEP P65

Read the position after the slash in the designation: 1P there means single pass. SWEP's example for this model is P65M/D-SC-S, which carries a D in that position, so go by what your nameplate shows.

On a frame this large, single-pass arrangements have a practical advantage: every connection is on one cover, so the unit can stand close to a wall and the pipework stays on one side. Multi-pass arrangements lengthen the flow path to get a larger temperture change from a given flow, at the cost of pressure drop and connections on both covers. With large-bore pipe at the back, that is a significant change to the installation.

Water, glycol solutions, oils and the common refrigerants are all within its range; 316/316L with copper braze is the general-duty construction.

Three fluids fall outside it. Ammonia attacks copper braze. Deionized or ultrapure water leaches copper out of the joints and contaminates the loop. Both need a copper-free construction. Chloride-bearing water - seawater, brackish or heavily chlorinated cooling water - pits 316 and calls for a higher-alloy plate. On gas vaporization duty, check the heating medium as carefully as the gas: it is usually the water side that carries the corrosion risk. Plate and Brazing Materials sets out the options.

The outline is 864 x 363 mm (34.02 x 14.29 in) and the port centres are 731 x 231 mm (28.78 x 9.09 in).

Depth and weight depend on plate count. SWEP's formula gives 1.07 kg (2.359 lb) per plate, so a 360-plate unit is around 385 kg (849 lb) dry. That is a rigging job: confirm the stand or frame can take it, that there is a lifting route to the position, and that the old unit's plate count is known so the depth matches.

SWEP publishes PED, UL and KHK for the P65. PED is the European pressure equipment approval, UL is the recognition North American inspectors look for on refrigeration components, and KHK is the Japanese high-pressure gas approval.

The practical point is what is not on that list. Some jurisdictions and some owners require an ASME stamp or a Canadian registration number on a pressure-containing exchanger of this size. If your project does, state it at the quote stage and we will confirm what can be supplied - it is a far easier question to settle before the unit is built than at inspection. Approvals and Certifications covers the envelopes.

The risk is real on both of its listed duties. As a chiller evaporator, loss of water flow with the compressor running freezes the channels. On gas vaporization the cold side can be far below the freezing point of the heating fluid, so a drop in heating flow does the same thing faster.

Glycol lowers the freezing point but does not remove the need for flow proof and a low-temperature cutout. It also has a cost: higher viscosity raises the pressure drop and lowers heat transfer, which on a unit this large means a meaningful change in plate count. Give the concentration with the duty so the selection is made on the real fluid.

These models are catalogued alongside the P65. Each has its own page with its dimensions, materials and part numbers.

SWEP B65 - Mixed plate pack, 361 plates, 685 GPM.

SWEP V65 - High-capacity evaporator on the B65 frame, 864 x 363 mm, up to 360 plates, 684.65 GPM max flow.