Precision Casting Equipment - Shell Molding Tower
The wind tower (also known as the shell drying tower) is a key equipment in precision casting (investment casting), mainly used for rapid drying and hardening of wax mold trees after coating with mortar. It accelerates the solidification of silica sol or water glass shells by controlling temperature, humidity, and airflow circulation, improving the efficiency and quality of shell making.
1. Core functions of wind towers
Drying and curing: Accelerate the chemical hardening of mortar (silica sol/water glass) to form a high-strength shell.
Environmental control: Adjust the temperature (20-30 ℃), humidity (40-70% RH), and wind speed (0.5-2m/s) to avoid cracking or deformation of the shell.
Multi layer shell making: supports multiple soaking, sanding, and drying cycles (usually 5-9 layers).
2. Equipment structure and working principle
(1) Main components
Tower body: enclosed space, lined with stainless steel/anti-corrosion materials, with multiple layers of brackets for placing wax mold trees.
Temperature and humidity system: air conditioning unit+humidification/dehumidification device, precise control of environmental parameters (± 1 ℃/± 5% RH).
Airflow circulation system: fan+guide plate to ensure uniform air flow and avoid dead corners.
Control system: PLC automatically regulates temperature and humidity, supporting multi-stage program settings (such as differentiated drying for different layers).
(2) Workflow
Soaking and sanding: After immersing the wax mold tree in mortar, sprinkle refractory sand (zirconium sand, corundum sand, etc.).
Drying in the tower: Move into the wind tower and start the set temperature and humidity program (such as 25 ℃/50% RH required for silica sol shell).
Cycle hardening: The drying time for each layer is about 2-4 hours, repeated in multiple layers until the desired thickness of the shell is achieved.
Preparation for dewaxing: After the final shell is removed from the tower, it enters the dewaxing furnace to remove the wax mold.