Low Formaldehyde & High Strength｜3D‑Printing Resin Empowers Efficient Production of Complex Valve Sand Cores
2026-08-24 09:02The implementation of the sand mold 3D printing technology brought significant changes for the foundry industry. The technology has become the most efficient way through which complicated parts with complex structure can be produced, as it is the one of the main components in rapid casting technology in modern manufacturing. Based on combining the computer-aided 3D design, the fundamentals of the additive manufactured method, and casting operations, the technology leads to mold-free quick setting of sand molds. The complex sand mold can be produced through the bonding of raw sand layer after layer which is quite suitable for making precise complex castings in small-batch production.
Valve casting involves internal curved flow channels, making the core-making process very difficult. Therefore, strict standards have to be followed during the core production for sand core surface finish, strength, and gas release, etc. Xinda focuses on Furan resin used for the sand mold 3D printing. The regular furan resin was modified for the creation of unique resin binders which consider several crucial casting indicators such as ambient temperature strength, gas evolution, shake out performance, and ecologically friendly characteristics. The 3D-printing resin and its curing agent are used for printing the valve sand-core, resolving the problems of complicated valve sand-core shape and sand-core performance.
Ⅰ、Key Technical Specifications of Products
| 3D Printing Resin | |
| Density (20℃) | 1.10‑1.20 g/cm³ |
| Viscosity (20℃) | 9.50‑10.5 mPa·s |
| Free Formaldehyde F.F. % | ≤0.1 |
| Nitrogen Content % | ≤0.5 |
| pH Value | 6.0‑7.5 |
| Particle Size μm | ≤0.5 |
| 3D Printing Curing Agent | |
| Density (20℃) | 1.20‑1.30 g/cm³ |
| Viscosity (20℃) | ≤15 mPa·s |
| Total Acid % | 18‑20 |
| Free Acid % | ≤1.5 |
Ⅱ、Production Process & Application Parameters
| Base Sand AFS | 63‑65 |
| Resin Addition Level (based on sand weight) | 2.10% |
| Curing Agent Addition Level (based on sand weight) | 4.0‰ |
| Layer‑Coating Thickness | 0.4 mm |
| 2‑hour Tensile Strength of Sand Mold | 0.67 MPa |
| 24‑hour Tensile Strength of Sand Mold | 1.52 MPa |
| Formaldehyde Emission at 3D‑Printing Site | 0.0317 mg/m³ |
Ⅲ、Practical Application Results
Low‑viscosity and high‑cleanliness resin ensures stable and smooth printing performance;
Formulated with mixed sulfonic acid, the curing agent delivers good flowability for favorable sand‑laying effect. It features low corrosiveness and will not damage sand‑mixing and sand‑laying equipment;
Low emission of harmful gases during core‑making process;
Sand cores achieve smooth surface and high strength, meeting production requirements for valve castings with complex inner cavities.
Xinda 3D printing resin and matching curing agent is well‑suited for 3D‑printing production of intricate valve sand cores. It provides stable printing performance and low equipment corrosion. The sand cores obtain excellent strength and surface quality, accompanied by low formaldehyde emission on‑site. Balancing casting quality and environmental‑protection requirements, the product is applicable to additive core‑making for various complex valve‑type castings.