The Y - type bellows globe valve is a globe valve with unique structural and performance advantages. The following is a relevant introduction:
Structural Features
DC - type Valve Body Flow Passage The flow passage of the valve body of the Y - type bellows globe valve is of the DC - type. Compared with the straight - through structure, it has a smaller fluid resistance, which can accelerate the flow rate of the medium, reduce pressure loss and energy consumption. It is especially suitable for viscous and caking media.
Dual - seal Design It adopts a dual - seal structure consisting of a bellows and packing. If the bellows fails, the valve stem packing can serve as a second - line defense to prevent leakage, meeting international sealing standards.
High - quality Sealing Surface The sealing surface is surfacing - welded with Co - based hard alloy, which has good wear - resistance, corrosion - resistance, and anti - friction properties. This ensures reliable sealing of the valve disc and a long service life.
Special Valve Stem Treatment The valve stem usually undergoes quenching and tempering as well as surface nitriding treatment, resulting in good corrosion - resistance and anti - friction properties.
Valve Stem Lifting Indicator Some valves are equipped with a valve stem lifting position indication device, allowing for an intuitive understanding of the opening and closing state of the valve.
Advanced Valve Body Manufacturing Process Some products adopt the German coated sand casting technology, which improves the surface finish and mechanical properties of the valve body, reduces defects such as pores, sand inclusions, and cracks, and enhances the tensile strength of the casting.
Anti - vibration Device For products with a DN of 150 and above, a special device may be installed to effectively prevent the valve from vibrating, making noise, and suffering internal component damage during use. The service life can be effectively increased by more than 150%.
Working Principle
Similar to ordinary globe valves, by rotating the handwheel, the threaded guide sleeve rotates. Due to the anti - rotation block restricting the rotation of the valve stem, the rotational motion of the handwheel is converted into the up - and - down linear motion of the valve stem. Relying on the pressure of the valve stem, the sealing surface of the valve disc is closely fitted to or separated from the sealing surface of the valve seat, thus achieving the function of blocking or allowing the passage of the medium. In the Y - type bellows globe valve, the lower end of the bellows is welded to the valve stem, and the other end is placed between the valve body and the valve cover to form a static seal, preventing the process fluid from corroding the valve stem.
Performance Parameters
Nominal Pressure Generally applicable to different grades such as PN1.6 - 10.0MPa.
Nominal Diameter Common sizes range from DN15 - DN600.
Operating Temperature It can usually operate in the temperature range of - 29 - 350°C, with specific values varying depending on the material.
Applicable Media Including steam, heat - transfer oil, molten salt, water, oil products, gases, natural gas, nitric acid - based substances, particulate media, petroleum, chemical raw materials, toxic media, etc.
Application Fields
Petrochemical Industry Used in the pipelines for transporting petroleum and chemical products, it can effectively control the flow of fluids and prevent leakage under harsh working conditions such as high temperature, high pressure, and corrosive media.
Power Industry Often used in the boiler and steam pipeline systems of power plants to control the flow of high - temperature steam, ensuring the safe and efficient operation of power equipment.
Pharmaceutical Industry In various fluid medium pipeline systems in the pharmaceutical process, it can meet the strict requirements for tightness and cleanliness.
Water Treatment Industry It can be applied to high - pressure water pipelines and treatment equipment to provide reliable fluid control.
Other Fields It is also widely used in industrial fields such as chemical fiber textiles, plastic paper - making, printing and dyeing rubber, and food.
Installation and Maintenance
Installation It can be installed on horizontal or vertical pipelines, but the inlet and outlet directions of the valve should be consistent with the flow direction of the medium. At the same time, sufficient space should be reserved for operation and maintenance.
Maintenance Regularly check the sealing performance of the valve, the lifting and lowering of the valve stem, and the condition of the bellows. If there is leakage or any abnormality, it should be dealt with in a timely manner. Lubricate parts such as the valve stem and nut to extend the service life of the valve.
