10 Tips For Plate-and-Frame Heat Exchangers

You may select a plate-and-frame heat exchanger that is ideal for your use by analyzing your process.

Plate and frame heat exchanger (PHEs) is known for their high heat transfer efficiency. However, as a specifier or user of PHEs, there are a few things to bear in mind. If the PHE is going to be utilized with a cooling tower, it must be constructed for the water treatment chemicals that will be used to purify the tower water. Furthermore, it is simpler to avoid a heat exchanger from escaping than it is to stop one that has already occurred. Did you know that reducing nozzle velocities can help to reduce erosion in the port area?

When selecting and operating your next plate heat exchanger, keep the following ten suggestions in mind.

Tip #1: To Avoid Warranty Issues, Use OEM Components

It is common to find companies willing to offer non-original manufacturer components at reduced prices, as is the case with all types of equipment. Some of these businesses give enough engineering and after-sale assistance, while others do not. Before coming to a decision, carefully analyze the potential benefits and downsides of purchasing non-OEM replacement components.

Tip #2: Plan for the Future, But Shop for What You Need Now

One of the greatest advantages of a plate-and-frame heat exchanger, aside from its heat transfer efficiency, is its adaptability. If your heating/cooling needs change over time, you can easily adapt by adding or subtracting plates within the frame. This flexibility allows you to buy the equipment you need just now while knowing that your future growth needs will be met with a little forethought. The head and follower will stay the same once bought. For every brazed plate heat exchanger model, most manufacturers provide a variety of frame lengths.

Tip #3: Take Steps to Prevent Port Erosion

Keep the port velocity at the heat exchanger at 20 feet per second as a fair general rule. Even in water applications, contemplate port liners made of the same material as the plates. In high-flow, abrasive settings, these liners, which come in a variety of alloys, will shield the carbon steel head against corrosion and erosion. For instance, in sea (salt) water, a carbon steel frame featuring titanium port liners and plates is standard. This method ensures that all saltwater-contact components are manufactured of corrosion-resistant titanium.

Tip #4: Follow Proper Piping Procedures

Decent, common-sense plumbing procedures should be implemented with all process equipment. A flat plate heat exchanger is ineffective as a pipe hanger. Verify that all pipework is correctly supported and that the links to the heat exchanger are not under any undue stress.

Tip #5: Check Plate Pack Dimensions Plus Frame Integrity Regularly

Based on the number of plates and grids in the device, the manufacturer will supply a total dimension of the plate pack. The distance between the interior of the head and the follower is determined. At least once a year, you should check this measurement and, if required, tighten the unit. Assess the frame components and tie-bars for any corrosion or damage that may occur when in a chemical environment.

Tip #6: Keeping Big Particles Out 

Because particles bigger than 0.0625″ can get stuck in the plate channel and cause damage to the heat exchanger, it is critical to guarantee that no particulate larger than this size is permitted to enter. If your liquids include bigger particles, strainers or separators should be used to remove them before they reach the exchanger. This is especially critical if the system has an open tank where bigger particles might enter.

Tip #7: During Startup, Use a Strainer or Bypass the Unit

During startup, a provisional strainer should be installed on the hot or cold water intake, as well as the process liquid input. Alternatively, you can turn off the heat exchanger entirely at startup. For fresh, startup applications, an interim strainer or bypass design around the brazed plate heat exchanger is advised, even if your liquids are pure and free of particles.

Tip #8: Stay Away from Circumstances Where Pressure Spikes are Likely to Occur

Even though manufacturers include extra allowances in the design engineering, it is critical to keep within the heat exchanger’s pressure restrictions. If a pressure surge in the system piping is probable as a result of rapid valve closure, water hammer, or other factors, you must take the required safeguards to protect the heat exchanger or risk the leaking repercussions of a blown-out elastomeric gasket. Temperature variations of greater than 20oF/min (11oC/min) and changes in pressure of over 150 PSIG/min should be avoided. Arrestors, pulsation dampers, rupture discs, and relief valves are all options for dealing with this problem. Consult the manufacturer for suggestions.

Tip #9: Make Sure You’re Compatible

Verify with your manufacturer to confirm that the plate heat exchanger components, as well as any conceivable cleaning solutions, are chemically compatible. Some manufacturers use 316 stainless steel with a greater nickel content, which is more chlorine resistant, but it’s best to double-check with them before making any chemical changes.

If you’re thinking about using more harsh chemicals to combat a problem like algae in the cooling tower, verify with the plate and frame heat exchanger manufacturer to be sure the plates and gaskets are compatible.

Make sure the cleaning solutions you’re using are safe for the heat exchanger plates and gaskets.

Tip #10: Tell Them all There is to Know

When requesting a quotation from a manufacturer, make sure to provide all important details about your application.

Most manufacturers offer a design questionnaire that you may use to collect data for a flat plate heat exchanger application, and they would be happy to provide you with a copy.