BBG GROUP
PUR Insulation of Hot Water Storage Tanks: Cost-Effective Production Even in Small Quantities
Small production batches, varying tank dimensions, and numerous design configurations present particular challenges for manufacturers of hot water storage tanks. To meet applicable thermal insulation requirements, many manufacturers rely on rigid polyurethane (PUR) foam. However, investment in the required production equipment can become a significant cost factor.
Flexible universal molds or the direct introduction of foam between the inner tank and its outer casing enable cost-effective production, even with small batch sizes and a wide variety of tank designs.
Different Manufacturing Concepts for PUR Insulation
Conventional foaming molds are tailored to the geometry of each hot water storage tank. Universal molds, on the other hand, use adjustable components and interchangeable inserts to accommodate different tank sizes and configurations within a common mold system.
Another option is to introduce the foam directly between the inner tank and its outer casing. In this process, the outer casing, which remains a permanent part of the finished tank, defines the foaming cavity. This eliminates the need for a foaming mold that encloses the entire tank.
PUR Insulation Directly Between the Inner Tank and Outer Casing
In this process, rigid polyurethane foam is introduced directly into the space between the steel inner tank and its plastic outer casing, which remains part of the finished product. As the PUR reacts and expands, it fills the cavity and forms the insulating layer.
Uniform insulation requires precise positioning of the inner tank as well as reliable sealing and containment of the foaming cavity. Depending on the tank design, suitable assembly and positioning fixtures are used for this purpose.
The temperature required for the foaming process is achieved by preheating the preassembled, uninsulated tank, for example in an oven. Selecting a suitable PUR system and matching it to the manufacturing process are also essential for reproducible results.
Advantages for Small Production Volumes and a Wide Variety of Tank Designs
This manufacturing process can be particularly attractive for manufacturers producing different tank sizes in relatively small batches. Eliminating the need for a foaming mold that encloses the tank creates new opportunities for cost-effective production.
Several potential advantages result from this approach
- Lower investment costs: Eliminating the need for variant-specific foaming molds can reduce the initial investment.
- High product variety: Tanks with different heights, diameters, and connection positions can be insulated using suitable assembly and positioning fixtures.
- Scalable level of automation: Many process steps can be performed manually or with partial automation. Further automation is also possible in principle as production volumes increase.
Whether this manufacturing process offers economic advantages must be evaluated on a case-by-case basis.
Customized Production Solutions for PUR Insulation
BBG develops and manufactures molds, machines, and production systems for polyurethane processing, among other applications. For the thermal insulation of hot water storage tanks, we offer different manufacturing concepts tailored to specific requirements.
Working closely with our customers, we develop solutions that meet both the technical requirements of the products and the economic conditions of production.
Looking for a suitable solution for the PUR insulation of hot water storage tanks?
Contact us to discuss your requirements. Together, we can develop a manufacturing concept tailored to your needs.