ASCO 551 Series Proportional Solenoid Control Valve from China
This pneumatic actuator-equipped control valve modulates flow precisely based on electrical signals from a PLC in semiconductor wafer processing systems. It falls under HTS 8481.80.9035 due to its design for proportional operation by a control device signal, specifically for gas delivery in crystal growers. Used in Czochralski pullers to maintain stable pressure during silicon boule formation.
Duty Rate — China → United States
37%
Rate breakdown
9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
Import Tips
• Verify pneumatic actuator specifications and signal compatibility (4-20mA or 0-10V) match US safety standards like UL or CSA for semiconductor equipment
• Include detailed flow curves and Cv values in documentation to prove proportional control function and avoid misclassification as simple on/off valves