Pillow plate

What Are Pillow Plate Heat Exchangers?

As engineers and consultants, we all know that the design of a pillow plate is an essential factor when it comes to process efficiency, heat transfer performance and cost-effectiveness. With proper engineering expertise and thoughtfully designed plates, you can streamline operations, maximize thermal exchange across different media efficiently and reduce energy consumption significantly.

A single or double embossed pillow plate heat exchanger often is very flexible coupled with design, surface and mechanical requirements for either heating or cooling. Especially pillowplate voulme contents are considerably smaller than those of comparable tubular heat exchangers and dependent on the weld seam distance and the pressure height. It is our daily task to design and manufacture pillow plates. With the right knowledge and know-how of pillow plates, you can ensure optimal heat transfer solutions. There’s nothing more important to us than helping our customers find the exact pillow plate solution they need.

Single Embossed Pillow Plate for food contact cooling

Possibilities of single embossed pillow plate in application of a contact freezer plate for food, e.g. meat, fish and chocolate pralines.

What are the advantages of a Pillow-Plate?

  • Individual designs of a single and double embossed pollow plate heat exchangers in size, shape and material enable flexible use due to a freely programmable CNC laser welding system.
  • Lots of heat exchange surface in little space due to small thermoshelf spacing of up to 2mm clear width.
  • High efficiency due to favourable flow routing (counterflow and crossflow).
  • Low pressure loss in the shell space due to flat parallel ducts.
  • Attractive investment costs of a pillow plate heat exchanger due to thin-walled plates and an automated laser welding process
  • Low operating costs due to smaller quantities of cooling or heating medium in small plate volumes of pillow-plates.
  • Good cleanability of a pillowplate (aswell with contaminated medias) due to flat surfaces compared to pipes our mounted plate heat exchangers that are difficult to clean.

What is a Pillow Plate?

A single or double welded pillow plate is made of two metal sheets of either a different or the same wall thickness, welded together by using laser or resistance welding. By a special inflation process, fluid channels are created between these two heat exchange plates. These plates are expanded until the desired and calculated channel height. The channel height describe the maximum space between the welded together metal sheets. All single and double embossed pillow-plate heat exchangers profiles and wall thicknesses are selected for throughput, allowable working pressure and pressure drop requirements from us as pillow plates manufacturers.

When it comes to pillow plates, there are two main types to consider: single-embossed and double-embossed. Although both have their applications, single-embossed plates are commonly used as the double walls of jacketed vessels. These plates are designed with a thicker base plate and a thinner top plate. As a result, the top plate deforms while the base plate remains unaffected. With this knowledge, manufacturers can create specialized pillow plate heat exchangers with ease.

As industries continue to strive for maximum efficiency, the use of pillow plate heat exchangers has become increasingly popular. These heat exchangers are equipped with innovative "pillow" seam weldings, which provide targeted flow guidance in the channels of the pillow plate. In situations where fluid velocity or distribution is a concern, these weldings can be the perfect solution. Recently, a method for obtaining flow guidance by cushions in the channels between adjacent pillow plates has been proposed. This exciting development has the potential to improve the performance of heat exchangers even further, enabling industries to operate with greater efficiency and reduced costs.

How does a Pillow Plate Heat Exchanger work ?

The connecting pipe work to the single and double embossed pillow plate has to be laid in a way to ensure that tensions due to thermal and mechanical expansion will not lead to damage of the plate connections. The weight of the connecting pipe work has to be supported by suitable supports. If not included in the scope of delivery, we recommend as pillow plate manufacturers the use of expansion bends and/or expansion joints. Connection seams that have to be welded to the connections have to be carried out and checked in accordance with valid and authorized welding procedures.

For the transfer of large amounts of heat or for a uniform temperature distribution inside a tank, it is recommended to install a double-profiled pillow plate heat exchnger directly inside the tank in the form of a heat exchange system. In tanks with agitators, the double embossed pillow plate also serve as guide surface for the flow. This contributes to the optimal mixing and to homogeneous heating or cooling.

We have a team of experienced engineers who are experts in developing specialty engineered thermal equipment that meets all our customer's needs. If you are looking for something unique, systems that provide temperature control and uniform heat transfer surfaces, get in contact with us today. Our commitment is to help you achieve efficient processing results, cost-effectiveness and minimal downtime. Call one of our specialists for reliable advice or to book an appointment now!

Optimal solution with pillow plates based on the customer’s data and requirement

Our project engineers are experts in thermodynamics and fluid mechanics, enabling them to provide the ideal solution for any heat transfer task. After a close collaboration with the customer's plant manufacturer or operator, our specialized CAD-designers will craft an optimized 2D or 3D design that meets all requirements precisely.

The pillow plate design presents a unique challenge for engineers seeking to optimize heat transfer rates while minimizing pressure loss. The complex wavy geometry of the channels within these plates can promote fluid mixing, which can be beneficial for heat transfer, but at the same time can pose challenges in reducing the formation of recirculation regions in the wake of welding spots. Fortunately, valuable information exists on fluid flow and heat transfer behavior in pillow plates, as well as correlations for calculating Darcy-Friction-Factor and Nusselt number across a wide range of geometrical parameters and process conditions. With this knowledge in hand, engineers can confidently design and optimize pillow plate systems for a variety of applications.

Our pillow plates are expertly produced on advanced laser welding machines, while resistance welding is an option for projects that require specialized materials. Ensuring the highest quality products possible, our team of European welders monitor and supervise every stage during production. We offer top-of-the line pressure equipment components certified by 2014/68/EU with a TR CU certificate as well as adherence to ASME standards in order to meet any required needs across industries.

Pillow Plate heat exchange panel welding contours in any shape

As industries continually search for new ways to optimize their processes, pillow-plate heat exchangers are emerging as a highly sought-after solution. Compared to traditional heat exchangers, they are relatively new, but their unique "pillow-shaped" design provides greater flexibility and efficiency in heating and cooling systems. What sets them apart is their ability to serve as both plate-type heat exchangers and jackets for vessels. As a result, they are becoming increasingly implemented in the process industry. These fully welded heat exchangers represent a highly versatile technology that is changing the game for many businesses.

CNC-controlled laser welding equipment enables us to produce pillow plates with a variety of shapes, from the simplest rectangular ones to more complex contours. Thanks to this technology we can now create cut-outs in any shape and size for pipelines or cables' feed. Additionally, it allows us flexible flow design adapted to heat transfer rate and pressure drop optimization.

With their unique design, pillow plates offer a promising alternative to conventional heat exchangers. However, their thermohydraulic performance remains relatively unexplored, leading to limited knowledge and experience with their design. In response to this challenge, the industry is actively pursuing the development of commercial software tools that will facilitate research on pillow plates. If successful, such tools could unlock new possibilities for this innovative technology, making it more widely accessible and beneficial for a range of industrial applications.

Core business of pillow plates

Our team of skilled professionals are experienced at delivering cutting-edge solutions for process engineering, thermodynamics, fluid mechanics and more. With decades of experience in the design and manufacturing heat exchange plates we remain committed to understanding individual requirements from a range of industries - so our solution meets even your most specific needs. Anywhere across the world, plant manufacturers or engineers can rely on us to provide precise analysis with tailored advice that's perfect for their heating/cooling processes.. We strive to create solutions specifically tailored to our customers' needs, balancing technical and economic considerations. With know-how gained over decades of experience in the industry, we provide comprehensive support for worldwide clients; not only during planning design but also on integration into their systems - reducing potential risks that arise from interfaces.

Pillow plates offer a versatile and flexible solution for a wide range of applications. Their impressive properties, including high geometric flexibility and adaptivity to different processes, make them ideal for various purposes. While the external surface is easy to clean and is perfect for high fouling or sanitary applications, the internal surface is not suitable for such purposes. The internal surface has fine seams around each spot weld, making it challenging to clean. Therefore, non-fouling fluids like water, steam, or refrigerants are the only suitable fluids for the internal surface. Pillow plates are an excellent choice for many industries, including food and beverage, chemical processing, energy, and many others.

Pillow-plates in heat exchanger applications?

Usually a single embossed pillow plate is mainly integrated into process tanks, bulk or pressure vessels, as well as it is integrated into cooling tables or conveyer structures, uniquely due to their one flat inside surface of the pillow plate heat exchanger.

Conversely double embossed pillow-plate heat exchangers have an unlimited access to all industries, in which cooling or heating are part of the main manufacturing process. Ordinarily a distinction is made between a pillow plate with spot patterns and those, which have a defined channel pattern.

Heat exchange surfaces are calculated due to each individual process application. Above all, the flexible design options of single and double embossed pillow plate allows tempering of products during other process steps. Although this saves a separate thermal process stage and often increases product quality. Furthermore, the large single and double embossed pillowplate heat surface ensures safe process control by controlled homogeneous temperature control.

Standard connections for pillow-plates

For a double embossed pillow plate heat exchanger, the standard connections can be either lateral or butt-welded. In the reinforced version, the double embossed pillow plate is drilled through on the inside and the tube welded to the plate on both sides.

The fluid connection to the single and double embossed pillow plate heat exchanger are either by flanges, welding nozzles or screw pipe connections. Please note that the projected flow direction for the heat transfer fluid has to be adhered to. In case of screw connections these should be re-tightened during operational conditions after a certain operational period. The single or double embossed dimple plate does not have any electric connection. In the meantime, however, the U-values ​​are only negligibly affected by soiling or a deposit on the dimple plates. Similarly favorable temperature differences then result in a significantly better efficiency compared to compact external heat exchangers. At the same time, the products, especially food, are treated very gently.

Fouling, maintenance and cleanability

Problems in the stirring technology when used in agitator tanks are largely known. In general, chemical reactions in agitator vessels require heat exchange surfaces to heat or cool products. Coils are still mainly used in tanks for heat exchange, but they have enormous disadvantages with regard to fouling, cleaning and maintenance. Star-shaped heat exchange systems with double embossed pillow plates offer a lot of advantages.

On the one hand side the flow angle can be adjusted according to the medium, on the other hand, this flow breaker pillow plate heat exchanger system is at the same time a heat exchange surface. Compared to coils in combination with conventional flow breaker systems with coils, this plate version has the following advantages, such as clean, low-polluted surfaces (especially with electropolished pillow plates), small heat transfer medium quantities, optimum heat transfer, optimization of the pressure drop and adjustment of the mass flow angle. As pillow plate manufacturers, we have long experience to calculate and ensure performance.

High demands on surface finish

In galvanic industry, particularly high demands are placed on the heat exchanger with regard to material, surface finish, easy cleaning and easy interchangeability. Especially in temperature-controlled processes, the uniform and gentle heat input is important. For this reason, people today turn away from systems operated with circulating air. Although the described double embossed pillow plate plate system can also be used in this application, for example for heat exchange in sterilization ovens, drying cabinets in the pharmaceutical industry and industrial drying ovens. It guarantees absolutely even heat mass flow and low pressure drop due to large flow cross sections of the pillow plate heat exchanger.


Materials used, are mainly stainless steel as to be AISI 304 up to titanium. Stainless steel’s low thermal conductivity is partially counteracted with the ability to design thinner walls, because of its high strength and corrosion resistance. As where carbon steel in the process fields, is mostly selected due to higher thermal conductivity. Subsequently as pillow plate manufacturers, prepickled, brushed or polished metal sheets can be used.

Certifications, classifications and designs

Single and double embossed pillow plates have been designed, built and tested as a pressure equipment. Therefor they are supplied with an European Pressure Equipment Directive 97/23/EC are certified by CE labeling and a declaration of conformity. If agreed, additional certificates can be issued.

Together with the fittings (e.g. tubes with welded ends, flanges or threaded socket ends) these channels form a pressure chamber, through which a fluid will pass to transfer heat to/from the room enclosing the single or double embossed pillow plate heat exchanger. Depending on the channel cross-sections, the volume of any pillowplate varies. Please find details about the design, dimensions connections and authorized operational conditions in the drawings as well-known pillow plate manufacurers.

If the single and double embossed pi enclosing chamber are also a pressure chamber (vacuum or pressure > 0,5 bar above ambient) this has been considered in the design.

What are the advantages with Pillow-Plates?

  • Individual designs of a single and double embossed pillow plate heat exchanger in size, shape and material enable flexible use due to a freely programmable CNC laser welding system.
  • Low material costs due to the use of thin sheets for pillow-plates.
  • Integration into vessels for mechanical and thermal doublefunction with a pillow plate.
  • Very homogeneous temperature gradient, product-gentle and conciliatory tempering of products by liquids, refrigerants and steam.
  • Smaller quantities of refrigerant or heating medium due to small plate volumes of pillow-plates.
  • High heat transfer coefficient with low pressure drop in case of a thermoplate.
  • Heat transfer or radiation protection over entire surface of a welded pillow plate.
  • Lower tendency for fouling for a welded pillow plate.
  • Low intertia.
  • Better mechanical resistance to thermal cycling with pillow-plates.
  • Long lifetime due to individually chosen materials.
  • Low production costs due to automated welding process for a pillow plate.
  • Easy cleaning due to easily accessible single or double embossed pillow plate prime surface.
  • Reliability.

Single or double embossed pillow plate technical data

  • Sizes from DIN A5 up to 14000 x 2000 mm.
  • Up to 50 bar operating pressure.
  • Wall thickness from 0.8/0.8 up to 3.0 / 3.0 mm with double embossed profile.
  • Up to 12 mm groundplate with single embossed profile.
  • Rolled dimple plates aswell.
  • Surfaces: stained, ground, polished.
  • Certificates according to TÜV , PED , TR CU (GOST) and ASME.

Single or double embossed pillow plate specifications

  • Single and double embossed dimple plate heat exchanger for water, glycol, liquid nitrogen, thermal oil or steam.
  • As a single and double embossed dimple plate evaporator for all refrigerants with pump or injection operation.

Single and double embossed pillow plate applications and benefits

For over 50 years Pillow Plate manufacturers of BUCO single and double embossed pillow plate heat exchangers.

Single embossed pillow plate with TIG edge welding
Single embossed pillow plate with TIG edge welding
Double embossed radiation pillowplate
Double embossed radiation pillowplate
Double embossed dimple plate with defined spot and guided welding
Double embossed dimple plate with defined spot and guided welding
Single embossed dimple plate as a flat frying plate
Single embossed dimple plate as a flat frying plate
Simple embossed dimple plate as a frying plate with edge stability
Simple embossed dimple plate as a frying plate with edge stability
Double embossed dimple plate as cylindrical ring in relief
Double embossed dimple plate as cylindrical ring in relief

We have always assimilated engineering science and thermodynamics optimally in the various manufacturing processes.

Thermodynamicists,mechanical engineers and welding engineers define the dimensioning, design and construction of customised heat exchanger panels and systems in materials ranging from mild and austenitic steels through to titanium, and ensure successful distribution of their work worldwide.

In doing so they fall back on production engineering expertise and calculations developed in the course of the past hundred years that are still being continuously optimised in an ongoing process.

In the perception of our customers, the Buco product stands for:

Technical and process-oriented consulting
Thermodynamic efficiency
Quality and longevity