Alfa Laval M15 Gasketed Plate Heat Exchanger

A DN150 gasketed plate heat exchanger for medium-duty heating and cooling

The Alfa Laval M15 is a gasketed plate-and-frame heat exchanger from the Alfa Laval Industrial line, used in virtually all types of industry. The leaflet lists applications including energy and utilities, HVAC and refrigeration, chemicals, marine, steel, mining, pulp and paper, and water and waste treatment. Heat transfer area can be changed by adding or removing plates, the unit opens for inspection and cleaning, and it is available with single plates or with double-wall plates as an extra precaution against intermixing of fluids.

Technical specifications

Features that help with service and uptime

The design includes a five-point alignment and corner-guided alignment system, a chocolate-pattern distribution area, glued or clip-on gaskets, a leak chamber, fixed bolt heads with key-hole bolt openings, lifting lugs, pressure plate rollers and tightening bolt covers, depending on configuration. Extended pressure and temperature ratings may be available on request, and the global range printed in the leaflet may not be available in every region.

What to confirm before ordering

Send both fluids with flow rates, inlet and outlet temperatures, allowable pressure drops, design pressure and temperature, and the plate and gasket material suited to the fluids (for example chloride content for seawater cooling). Plate count and frame are then selected for the duty. A smaller unit is the Alfa Laval M6; see other cooling equipment under Cooling.

How the Alfa Laval M15 plate heat exchanger works

A gasketed plate heat exchanger is a stack of thin corrugated metal plates clamped between a fixed frame plate and a movable pressure plate. Gaskets around the plate edges and ports direct the two fluids into alternate channels, so the hot and the cold fluid flow on opposite sides of each plate without mixing. The corrugation pattern creates turbulence, which gives a high heat transfer coefficient for a small footprint compared with a shell-and-tube unit. In the M15 the port connection is DN150, so the unit suits duties with higher flow than the smaller M series sizes.

Because the plates are held together by tightening bolts, the heat exchanger can be opened for inspection, cleaning or plate replacement. The heat transfer area can be increased or reduced by adding or removing plates inside the frame, within the limits of the frame length, which makes the unit adaptable when the process duty changes.

Typical M15 applications

The leaflet names a wide industrial range. Within it, plate heat exchangers of this class are commonly applied to:

• District and building heating, HVAC and refrigeration circuits, where a heat exchanger separates a primary loop from a secondary loop.
• Energy and utility systems, including cooling of process water and engine or compressor jacket water.
• Marine and offshore cooling, where titanium plates are chosen against seawater.
• Chemical, steel, mining, pulp and paper processes where the plate and gasket material is matched to the fluid.
• Water and waste treatment plants with heat recovery between process streams.

Selection checklist for an Alfa Laval M15

• Both fluids, with flow rates, inlet and outlet temperatures and the heat load to be transferred.
• Allowable pressure drop on each side, since it determines plate count and channel arrangement.
• Design pressure and temperature, which decide the frame type: FL, FM, FG or FD, with the pressure and temperature ratings printed in the specification table.
• Plate type: M15-B with a 2.5 mm free channel, M15-M with a 4.0 mm free channel, or M15-BD double wall plates when intermixing must be prevented.
• Plate material suited to the fluid, such as stainless steel, titanium, nickel or the high-alloy grades listed, particularly where chlorides are present.
• Gasket material (NBR, EPDM, FKM, Q or HeatSeal) compatible with temperature and fluid chemistry.
• Connection standard, EN 1092-1, ASME B16.5 or JIS B2220, and any flange lining requirement.
• Installation space, using the frame dimensions and lengths from the leaflet, and room to open the frame for service.

Installation, commissioning and maintenance notes

The frame should stand on a level foundation with enough clearance beside it to slacken the tightening bolts and pull plates. Pipe connections must not impose loads on the frame ports, and shut-off valves should be fitted so the unit can be isolated for service. During commissioning, open the valves slowly to avoid pressure shocks, vent air from both sides and check the plate pack for leaks. In service, monitor temperature and pressure drop: a falling heat transfer or rising pressure drop usually points to fouling and the need for cleaning. Re-tightening and gasket replacement follow the manufacturer instructions, and the leak chamber and double wall plates give early warning in duties where mixing must be avoided.

Requesting a quotation for the Alfa Laval M15

To prepare a quotation, send the process data for both fluids, the design pressure and temperature, the plate and gasket material preference and the quantity. Seven Star LLC serves industrial customers in Oman and the GCC and replies with a quotation based on the information provided.

Documents and quotation

The attached Alfa Laval leaflet (CHE00073-4) gives the dimensional drawing, materials, operating data and flange connections. Send the duty data for a quotation.