Product Overview
The YDF series dome valve is a switching device used for conveying solid materials via gas. It serves to open and close the pipeline passage. This valve is suitable for sealed conveying systems handling loose, dry, non-sticky, and flowable solid materials, and is particularly well-suited for ash and slag handling systems in thermal power plants.
The dome valve’s shut-off function is achieved by a spherical valve core and an inflated rubber sealing ring, while the opening and closing operations are performed under zero-pressure conditions, thereby realizing non-contact displacement between the two states.
Depending on the application, the dome valve’s spool is made from different materials and undergoes various surface hardening treatments. Thanks to the spool’s smooth and hard surface, it can maintain close contact with the rubber sealing ring, ensuring reliable sealing performance. The rubber sealing ring is made from a special type of rubber that boasts exceptional resistance to high temperatures, corrosion, abrasion, and aging, thus providing a long service life. When the valve is opened, the material flow passage remains fully unobstructed.
This valve is suitable for use with gases, liquids, semi-fluids, and solid powders.

Installation and Usage Tips
1. Before installation, carefully read this instruction manual and verify the valve model, nominal diameter, and technical specifications.
2. Before the compressed air is released, it is strictly prohibited to open the valve.
3. Absolutely no water or wet materials are allowed to enter the valve.
4. Welding onto flanges immediately after installing valves is strictly prohibited to avoid damaging the valve’s sealing ring. The installation distance for valves pre-reserved in the pipeline should be appropriate, and gaskets must be added on both sides of the flange.
5. The centers of the two pipelines and the center of the valve’s bore should be coaxial, and the flange surfaces must be flat. Significant deviations in the flange surfaces are not permitted to ensure proper clamping and normal operation of the valve. When tightening the bolts, ensure that the tightening is even and symmetrical.
6. Regularly inspect the operation of the dome valve and promptly and correctly address and eliminate any abnormal conditions.
7. During lifting, installation, operation, commissioning, and maintenance, all other relevant safety operating procedures must also be strictly followed.
8. This valve has been adjusted and subjected to dynamic testing before leaving the factory, and the air lines have already been connected.

Main Technical Parameters

Nominal pressure: 1.0 MPa; Medium temperature: ≤250℃
Strength test: 1.5 MPa; Sealing test: 1.1 MPa
The operating pressure of the cylinder is 0.4 MPa to 0.6 MPa.
The inflation pressure of the sealing ring shall be 0.4–0.6 MPa, and it must be 0.15 MPa higher than the conveying pressure. Use clean, dry, oil-free compressed air.

External dimensions and installation dimensions

Size Parameter Table