Super Purchasing for Single-Lever Safety Valve - High-end gate valve for conventional island – Convista

Detail

The product is used for water supply system of nuclear power AP1000 unit. During its utilization, the gate valve must be in fully opened or fully closed position instead of serving as flow and pressure regulation.

Advantages

1. The valve adopts self-sealing structure and its both ends are welded connection.
2. The closing mechanism consists of wedge type dual-flashboard with adjustable center, universal top and hold-down board. Guided by guiding baffle in the valve body, it conducts up and down movements.
3. With cobalt-based rigid alloy build-up welding, the sealing surface features high temperature resistance, abrasion resistance, corrosion resistance, anti-scratching and long service life; build-up welding height of valve disc and seat ≥3mm.
4. With guiding baffle, the valve body provides total stroke guidance for flashboard opening and closing.
5. Undergoing anti-corrosion and nitrogenization treatment, the valve stem surface features good corrosion resistance, abrasion resistance and reliable stuffing box sealing.
6. The automatic wedge type dual-flashboard structure with adjustable center has the following characteristics: hardened top center and cushion block (spherical contact) can adjust matching angle between flashboard and valve seat automatically to make their sealing surfaces cling tightly and ensure tight sealing; a group of adjusting gaskets is installed between top center and flashboard to adjust width of flashboard and compensate abrasion after flashboard operation and repairing. Elastic groove is set between left and right flashboards to prevent stuck during valve closing. The structural flashboard has good interchangeability and huge manufacture difficulty, and its general cost is higher than parallel dual-flashboard and wedge elastic flashboard structures.
7. The valve adopts the structural type of welding-on valve seat. Magnetic powder detection is conducted for fillet weld to ensure welding joint quality complies with standard requirements.
8. T-type grooved connection is adopted for valve stem and flashboard of automatic wedge dual-flashboard gate valve with adjustable center. A hold-down board is set at T-type groove of the flashboard to limit opening of left and right flashboards after valve opening and preventing flashboard falling. Head of the valve stem is sphere. During valve closing, concentrated force is exerted by the valve stem on the hold-down board to make closing force more even during flashboard closing and guarantee even stress of flashboard and valve seat sealing surfaces and better sealing.
9. With pendant collet as the main stress part, the self-sealing part adopts forged part and its tissue compactness is superior to panel. Meanwhile, it adopts integrated ultrasonic detection and surface magnetic powder detection processes to ensure forged part quality comply with standard requirements.