In the field of modern industrial heat exchange, plate heat exchangers occupy an important position due to their high efficiency and compactness. As the core component of plate heat exchangers, plates directly determine the performance of the equipment. This article will briefly analyze the plates of plate heat exchangers from the aspects of structure, materials, craftsmanship, types, and maintenance.

I. Structure of Plates

Plates are made of thin metal sheets and consist of two key components: metal plates and gaskets.

The surface of the metal plate is pressed with corrugations, sealing grooves, and corner holes. Corrugations (such as herringbone, horizontal, vertical, inclined corrugations, etc.) can increase the surface area to enhance heat transfer, strengthen the rigidity of the thin plate to improve pressure-bearing capacity, and make the fluid in a turbulent state to reduce the adhesion of dirt.

Gaskets are installed in the gasket grooves around the plates, responsible for sealing the periphery of the plates to prevent fluid leakage, and sealing some corner holes according to the design to guide the cold and hot liquids to flow in separate channels.

II. Materials of Plates

The choice of plate materials has a significant impact on the application range, corrosion resistance, and service life of the equipment. Common materials include:

Stainless steel materials: 304 stainless steel is suitable for fluids with low chloride ion content; 316 stainless steel has better corrosion resistance in high chloride ion environments (such as seawater).

Titanium and titanium alloy materials: They have strong corrosion resistance, especially suitable for highly corrosive media such as seawater and brine, but the cost is relatively high.

Nickel alloy and alloy copper plates: Nickel alloys are heat-resistant and corrosion-resistant, suitable for high-temperature, high-pressure, and highly corrosive scenarios; copper alloys have good thermal conductivity and can improve the performance of the heat exchange system.

Special alloy plates: Such as 254SMO, which is resistant to pitting corrosion and stress corrosion cracking, and is suitable for harsh chemical and marine resource environments.

III. Manufacturing Process of Plates

One-time stamping forming: Precision molds are used for one-time stamping to ensure the accuracy of the plates, so that uniform metal point contact is formed between the plates, allowing the equipment to operate under higher pressure and withstand pressure shocks.

Advanced plate design: Combined with CAD/CAM technology and advanced pressing processes, the high precision of the plates is ensured, which is conducive to using thinner plates to improve heat transfer efficiency and reduce costs.

Distribution area design: The inlet and outlet nozzles with one-sided design need to solve the problem of uniform fluid distribution on wide plates. An excellent distribution design can achieve this goal with low pressure drop, which is beneficial to improving the heat transfer coefficient.

IV. Common Types of Plates

Single-channel plates: They have a simple structure, are easy to clean and maintain, and are suitable for scenarios with low requirements on flow rate and distribution, but the heat exchange efficiency is low.

Dual-channel plates: There are two channels for cold and hot media to flow respectively, with good heat transfer effect, suitable for various industrial heating and cooling processes.

Corrugated plates: The surface is wavy, with high strength and large surface area, high heat exchange efficiency, and widely used in evaporators and condensers, etc.

Multi-channel plates: Multiple channels can flexibly distribute heat, with high heat exchange efficiency and precise temperature control, suitable for scenarios with strict requirements on heat exchange.

Welded plates: Made by welding metal plates, they have a strong structure and can be used in high-temperature and high-pressure environments.

Reversing plates: Realize efficient heat exchange by changing the fluid flow direction, suitable for scenarios that require frequent reversal of fluid flow.

V. Maintenance of Plates

Plates are prone to scouring, corrosion, and dirt accumulation during long-term use, so maintenance is essential: regularly clean to remove dirt and restore heat transfer performance; pay attention to corrosion, and take anti-corrosion measures for easily corroded materials; ensure stable operating parameters of the equipment to avoid severe fluctuations that damage the plates. Doing these well can extend the service life of the plates and ensure the stable and efficient operation of the heat exchanger.

Although the plates of plate heat exchangers are small, their structure, materials, craftsmanship, and types together lay the foundation for the efficient heat exchange of the equipment. Reasonable selection and maintenance of plates can enable them to continuously create value for various industries.