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olyurethane PU Foam Aerosol Tin Can: Special Structure and Sealing Process Design Under High Pressure Expansion
2026-04-24
In construction scenarios such as gap filling, seam sealing and wall insulation, the application demand of foaming agent aerosol canshas always remained high. Due to the special chemical ratio and expansion characteristics of PU foam, the inside of the can is in a long-term high-pressure state with mixed gas and liquid. Ordinary packaging cans cannot bear such high internal pressure load, which will easily lead to sealing failure and tank deformation. With years of professional experience in Tinplate Aerosol Can customization and manufacturing, SAILON focuses on the structural research and development of high-pressure explosion-proof foaming agent Aerosol Cans. Combining real application scenarios including long-term storage, outdoor construction and multi-layer logistics stacking, we develop customized tank design solutions that fully adapt to the properties of PU foam, balancing safety and practicality.
Unique Properties of PU Foam Promote Upgraded Custom Standards
The storage challenges of foam materials are often overlooked by many users. After being mixed and encapsulated with ether and hydrocarbon propellants, polyurethane foam will generate dynamic internal pressure through continuous chemical reactions. Ambient temperature changes will further aggravate pressure fluctuations — when the storage temperature rises above 50°C in summer, the internal pressure of the can may even exceed 30% of the conventional value. The pressure resistance of conventional daily chemical aerosol cans is too low to adapt to the harsh storage conditions of PU foam.
According to the current professional industry standards, special tinplate cans for PU foam need to stably withstand a normal working pressure of 15bar and reserve sufficient pressure buffer space. Simply thickening the tinplate cannot improve safety performance. Excessively thick plates will reduce the toughness of the tank and cause brittle cracks under external force such as extrusion and collision. The core logic to avoid high-pressure risks lies in scientific structural design, accurate material selection, as well as professional inner wall protection and sealing technology.
Core Performance Comparison: General Can vs. Industrial PU Foam Special Can
The gap between industrial foaming agent aerosol cans and ordinary daily chemical aerosol cans is reflected not only in pressure-bearing capacity, but also in every detail of structural design and process standards. The specific comparison is as follows:
| Performance Metrics | General Daily Chemical Aerosol Can | Industrial PU Foam Special Can |
|---|---|---|
| Structural Design Logic | Adapt to low-pressure mild materials | Adapt to dynamic expansion characteristics of PU formula |
| Standard Working Pressure | 6 - 8 bar | ≥ 15 bar (1.5 MPa) |
| Bottom Cover Structure Standard | Concave Bottom | Reinforced Inverted Deep Dome |
| Core Function | Basic Pressure Bearing | Disperse internal pressure to prevent bottom cover eversion |
| Top Cover Shape | Flat or Low Curvature | Integrated High Tapered Top Cover |
| Core Advantage of Top Cover | Simple and Easy to Produce | Improve valve sealing stability and adapt to glue guns |
| Sealing Process Standard | Basic Double Crimping | Three-piece High-frequency Welding + Reinforced Crimping |
| Core Sealing Function | Prevent Minor Leakage | Resist chemical solvent penetration and long-term high pressure |
| Burst Pressure Upper Limit | ~11.5 bar | ≥ 22.5 bar |
| Safety Redundancy Design | No Clear Redundancy | Reserve more than 1.5 times safety margin |
Inverted Dome Bottom Structure, Core Barrier Against High Pressure
All high-pressure resistant sealed aerosol cans adopt an inward concave inverted dome bottom cover, which is a mechanically optimized structural design rather than a simple aesthetic choice. The internal high pressure spreads evenly in all directions; a flat bottom will be pushed outward by internal pressure, resulting in unstable placement and irreversible cracking of bottom welds under long-term force. The design of the reinforced inverted deep dome can fundamentally solve this problem.
In the production process, SAILON adjusts the stamping and stretching technology of the bottom cover to optimize the molecular toughness of tinplate, and at the same time, with precise size control, the inverted deep dome can disperse pressure more evenly, further improving the deformation resistance of the tank. Even in extreme high temperature and high pressure environments, it can effectively avoid bottom cover eversion or bursting.
High Tapered Top Cover Design for Construction Operation and Fluid Delivery
In actual construction work, glue guns and extended guide tubes are widely matched with foam products. Frequent insertion, twisting and pressing will cause continuous external force on the can mouth. The inclined surface of the integrated high tapered top cover can disperse concentrated stress, avoid cracks and leakage at the connection of the can mouth, which is also the core difference in top cover design between industrial PU foam aerosol cans and ordinary cans.
In addition, the smooth diversion channel formed by the conical inner wall adapts to the high-viscosity characteristics of PU foam, reducing valve blockage caused by colloidal accumulation. Even in low-temperature environments with poor fluidity, it can maintain stable discharging efficiency, balancing construction convenience and tank safety.
Three-piece Can Core Technology: Weld and Sealing Details Determine Long-term Durability
Most industrial foam cans adopt mature three-piece tinplate integrated forming technology. The weld precision and the selection of sealing materials directly determine the service life and safety performance of the tank, which is also the core advantage of SAILON's customization service:
- Continuous high-frequency welding for side seams of the can body, precisely controlling the weld gap, effectively resisting high-pressure penetration, eliminating chronic leakage at tiny positions, and ensuring the structural integrity of the tank under long-term high pressure;
- Double-layer reinforced crimping and biting process at the upper and lower ports, filled with high-solid content, solvent-resistant sealing compound. This special sealing compound can effectively resist corrosion by chemical components in PU foam, which is the key to ensuring long-term sealing for more than 24 months;
- The inner wall of the tank is coated with Epoxy-phenolic internal coating, which is specially used to prevent slight chemical corrosion of tinplate by isocyanate components in PU foam, extend the service life of the tank, and avoid coating peeling from contaminating materials;
- Closed process inspection throughout the whole process, including simulation tests for high-pressure environments and high and low temperature environments, to check weak sealing points one by one, ensuring that each batch of finished products meets industrial standards.
During long-term sealed storage, the chemical medium inside the foam has slight corrosiveness, and ordinary sealing materials and inner wall coatings will gradually age and fail. The Epoxy-phenolic internal coating and high-solid content solvent-resistant sealing compound selected by SAILON can perfectly adapt to the characteristics of such materials, allowing the tank to maintain stable sealing performance under normal temperature storage and seasonal temperature changes.
Full-scenario Safety Compliance for Storage, Handling and Daily Use
Most propellants matched with foaming agents are flammable, which requires cans to meet strict airtight safety standards in addition to high pressure resistance. In scenarios including outdoor construction site storage, long-distance transportation and warehouse multi-layer stacking, cans need to resist multiple impacts from internal pressure, external extrusion and temperature changes. A design oversight in any link may lead to potential safety hazards.
Based on rich customized production experience, we optimize the overall structural strength of the tank for different use environments. Each batch of finished products undergoes sampling high-pressure tests, drop tests and sealing immersion tests to eliminate potential safety hazards from the production end. It not only meets the basic specifications of industrial material packaging, but also fits the customized needs of special tinplate cans for PU foam, providing comprehensive safety guarantee for use in different scenarios.
FAQ
Q: Why must the bottom of the foaming agent can be an inward concave dome?
A: To achieve optimal stress distribution. The inward concave dome structure uses the arch force principle in physics to evenly guide the internal high pressure above 15bar to the side wall of the can, effectively preventing the bottom cover from eversion or bursting under extreme pressure, and ensuring that the can can still stand stably in high temperature environments.
Q: What does the 15bar index of the foaming agent aerosol can represent?
A: This represents an industrial-grade safety redundancy standard. The internal pressure of polyurethane foam will increase sharply during summer storage or vibration. The rated pressure-bearing capacity of 15bar can ensure that the tank still maintains structural integrity when the ambient temperature reaches above 50°C, far exceeding the 8bar standard of ordinary daily chemical spray cans.
Q: Can slightly bulging foam cans after long-term storage continue to be used?
A: It is not recommended for further use. Tank bulging indicates that the internal pressure has exceeded the structural bearing limit, and the sealing layer has probably suffered invisible damage, which may be accompanied by damage to the inner wall coating. Continuous use may easily lead to material spraying, pressure release and other safety problems, and may also affect the use effect of the foaming agent.
Q: What structural details should be focused on when customizing high-pressure explosion-proof foaming agent aerosol cans?
A: Focus on three core details: first, the reinforced inverted deep dome design of the bottom cover, which directly determines the high-pressure dispersion effect; second, the Epoxy-phenolic internal coating on the inner wall of the tank and the high-solid content solvent-resistant sealing compound at the seal, ensuring long-term sealing and corrosion resistance; third, the weld precision of the can body and the high taper design of the top cover, adapting to construction operations and improving overall structural stability. These are also the core optimization items of SAILON's customization service.