Solutions for stuck or jammed ball valves in polysilicon plants

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The main reasons for the sticking or jamming of ball valves in polysilicon plants are as follows: 1. The deformation chamber of the valve seat’s leaf spring has poor sealing properties, allowing silicon powder to enter this chamber; as a result, the leaf spring becomes blocked and ineffective, which in turn causes the ball to get stuck in the valve seat, preventing proper opening and closing. 2. Silicon powder enters the cavity between the valve body and the ball when the valve is opened or closed, causing the ball to stick and preventing the valve from opening and closing properly. However, for this to happen, a certain working condition is required: the silicon powder must be moist in order to adhere to the interior of the chamber. Silicon powder does not cause such locking under dry or fluid conditions. The first scenario occurs when the silicon powder causes sticking in a dry or fluid state, that is, when the silicon powder enters the deformation chamber of the valve seat spring. Solutions to the above two problems that cause valve sticking: 1. The New York Company uses full “O”-ring balls, dual valve seats, and a plate spring loading mechanism. The valve seat design features a wide-edge scraper structure that enables the removal of silicon powder adhering to the ball surface during valve opening and closing, thus providing self-shredding and self-cleaning capabilities. The plate spring employs a dual graphite sealing structure; while ensuring valve sealing, it is also sealed off, preventing the medium from entering the plate spring’s deformation chamber and avoiding its blockage or failure, thereby allowing long-term use. 2. In the special case where moist silicon powder blocks the interior of the valve, causing it to stick and become unable to be opened or closed, New Jersey Company generally advises customers to improve the drying process of the silicon powder or to use the V-shaped hemispherical valve offered by the company, in order to completely resolve this blocking issue. The New Jersey ball valve features highly refined improvements in its design structure, and it incorporates a spraying technique specifically used in the U.S. aerospace industry (diamond spraying process). Its surface hardness ranges from HRC 76 to 78, the operating temperature is between 600°C and 650°C, and the friction coefficient is between 0.03 and 0.05. As a result, the service life of these wear-resistant ball valves in polysilicon production facilities exceeds that of imported valves.