Durable Pneumatic Diaphragm Valve with Enhanced Flow Control

The cast iron rubber - lined pneumatic diaphragm valve is a high - performance valve widely used in various industrial pipelines. It combines the strength of cast iron, the corrosion - resistance of rubber lining, and the convenience of pneumatic actuation, providing reliable flow control for different media.
2. Structure
Valve Body: Made of cast iron, which offers high strength and durability. The inner surface of the valve body is lined with rubber, such as natural rubber, nitrile rubber, or fluororubber. This rubber lining protects the cast iron from corrosion by various chemicals and media, extending the service life of the valve.
Diaphragm: Usually made of high - quality rubber materials. The diaphragm acts as a flexible barrier that separates the valve body into two chambers. When the valve is opened, the diaphragm moves upwards, allowing the medium to flow through; when the valve is closed, the diaphragm presses against the valve seat, cutting off the flow path.
Valve Cover: Installed on the top of the valve body, it is tightly connected to the valve body by bolts. The valve cover provides a mounting base for the pneumatic actuator and protects the internal components of the valve from external environmental factors.
Pneumatic Actuator: It uses compressed air as the power source. There are two common types: piston - type and diaphragm - type. The piston - type actuator can provide a large output force, suitable for large - diameter and high - pressure valves; the diaphragm - type actuator is simple in structure and sensitive in action, often used for small and medium - sized valves.
Valve Seat: Located inside the valve body, it is the sealing surface when the diaphragm closes. The valve seat is usually made of materials compatible with the diaphragm to ensure good sealing performance and wear resistance.
3. Connection Methods
Flange Connection: Flanges are welded or cast on both ends of the valve and the pipeline. The two flanges are tightly connected by bolts, with a sealing gasket placed in the middle to prevent medium leakage. This connection method is suitable for high - pressure and large - diameter pipelines, and is easy to install and disassemble for maintenance.
Wafer Connection: The valve is directly clamped between two pipeline flanges by bolts. It has a compact structure, small installation size, and low cost, and is suitable for applications with limited space.
Threaded Connection: Threads are machined on both ends of the valve, which can be screwed onto the corresponding threaded pipeline. It is simple to install and is often used for small - diameter and low - pressure pipelines.
4. Sizes
The size of the cast iron rubber - lined pneumatic diaphragm valve is usually represented by the nominal diameter (DN). Common sizes range from DN15 to DN500. The specific dimensions such as outer diameter, length, and height vary according to different nominal diameters and manufacturers' designs.
5. Pressure Ratings
Nominal Pressure: It indicates the maximum allowable working pressure of the valve at a specified reference temperature. Common nominal pressures for this type of valve are 1.0MPa, 1.6MPa, 2.5MPa, etc. In some special applications, higher nominal pressures such as 4.0MPa and 6.4MPa are also available.
Working Pressure: The actual pressure that the valve bears during operation. The working pressure should be less than or equal to the nominal pressure to ensure the safe and reliable operation of the valve.
6. Flow Characteristics
The valve has good flow characteristics. The smooth flow path inside the valve body reduces the flow resistance, allowing the medium to flow smoothly. The opening degree of the valve has a relatively linear relationship with the flow rate, which is convenient for precise flow control.
7. Advantages
Corrosion Resistance: The rubber lining and diaphragm effectively resist the corrosion of various chemical media, making the valve suitable for applications in chemical, pharmaceutical, and sewage treatment industries.
Good Sealing Performance: The diaphragm provides a reliable seal, preventing medium leakage and ensuring the normal operation of the pipeline system.
Fast Response: The pneumatic actuator enables the valve to open and close quickly, which is suitable for applications requiring rapid flow control.
Easy Maintenance: The simple structure of the valve makes it easy to disassemble, inspect, and replace parts, reducing maintenance costs and downtime.
8. Application Fields
Chemical Industry: For controlling the flow of various corrosive chemicals, such as acids, alkalis, and salts.
Water Treatment: Used in water supply and drainage systems, sewage treatment plants to control the flow of water and wastewater.
Food and Beverage Industry: Suitable for applications where hygiene and corrosion resistance are required, ensuring the quality of food and beverage products.
Power Generation: For controlling the flow of cooling water, chemical reagents, and other media in power plants.
 

• Detailed Photos

   

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  NOD(DN)	OD(mm)	Length(mm)	Height(mm)
  15	21.3	130	220
  20	26.9	140	230
  25	33.7	150	240
  40	48.3	170	260
  50	60.3	200	280
  80	88.9	250	330
  100	114.3	300	380
  150	168.3	350	450
  200	219.1	400	520
  250	273	450	600
  300	323.9	500	680
  400	406.4	600	800
  500	508	700	950

   
  Product Parameters