Air & Liquid Chambers

The center block is a crucial component of an air-operated diaphragm pump. It serves as a guide for the main shaft or diaphragm rod (depending on the manufacturer’s design), ensuring the smooth operation of other pump components.

Functions of the center block:

• Guides the main shaft or diaphragm rod: The center block provides a precise path for the main shaft or diaphragm rod, ensuring stable and accurate movement of these components.
• Coordinates air pressure: The main shaft or pilot shaft generates alternating pressure to shift the main valve spool. This reciprocating motion drives the pumping action.
• Exhaust air: In most designs, air is exhausted from the center block through exhaust ports and exits the pump via an air exhaust muffler. This effectively controls the amount of air expelled, maintaining stable pump operation without excessive noise.
• Reduces friction: Bearings and seals within the center block minimize friction between the main shaft and other components.

Center blocks are typically made of:

• Aluminum: A popular choice due to its lightweight, durability, and corrosion resistance. It is suitable for applications requiring durability and performance in harsh environments.
• Polypropylene: This chemical-resistant plastic is used in applications requiring high corrosion resistance, especially when pumping corrosive chemicals or in high-humidity environments.
• Other materials: Depending on the specific application, other materials such as stainless steel or cast iron may be used.

The air inlet cap connects the air supply to the pump system. Compressed air from the supply source enters the pump through the inlet cap and is regulated to create pressure that drives the diaphragm, causing the pump to cycle and pump fluid. For optimal pump performance, the inlet cap must be compatible with the air supply’s pressure and flow rate requirements. This process ensures synchronized diaphragm movement and uninterrupted pumping. Inlet caps often include control valves to regulate the airflow, allowing for adjustment of pump speed and performance. This prevents overpressure or underpressure, which can lead to operational issues. Inlet caps are typically made of polypropylene, aluminum, or cast iron.

• Polypropylene: Suitable for applications requiring high chemical resistance but not requiring excessive mechanical strength.
• Aluminum: Ideal for applications requiring lightweight and not exposed to harsh environments.
• Cast iron: Often chosen for heavy-duty industrial applications requiring high pressure and durability.

The diaphragm chamber is where the conversion of pneumatic energy into mechanical force occurs, allowing the diaphragm pump to handle a variety of fluids, from chemicals to highly viscous liquids. The diaphragm chamber design enables the pump to operate without rotating components, as found in centrifugal pumps, minimizing mechanical wear. The diaphragm chamber consists of two main parts: the inner chamber (air chamber) and the outer fluid chamber, each with distinct roles and structures.

• Inner chamber (air chamber): The inner chamber contains compressed air and is responsible for transmitting force to the diaphragm. Compressed air is alternately introduced to both sides of the chamber, creating a reciprocating motion. This air pressure acts on the rear side of the diaphragm, causing it to displace and generate fluid pressure.
• Outer fluid chamber: This chamber directly contains and guides the fluid through the pump. It is sealed to the inlet and outlet pipes using gaskets and seals. As the diaphragm moves, it creates a void in the outer chamber for industrial pumps, drawing fluid in. When the diaphragm moves in the opposite direction, the fluid is expelled from the chamber through the outlet. The outer chamber for industrial pumps is designed to withstand fluid pressure and ensure a tight seal with the diaphragm, preventing leaks and maintaining a steady flow.

Diaphragm chambers are typically made of:

• Aluminum: Lightweight and easy to install, suitable for light or medium-duty applications.
• Cast iron: Durable and capable of withstanding high pressure, commonly used in heavy-duty industrial applications.
• Nylon: Lightweight and abrasion-resistant, often used in applications involving mild chemicals.
• Polypropylene: Highly chemical-resistant and unaffected by many solvents or chemicals.
• PVDF (Polyvinylidene Fluoride): A high-temperature and chemical-resistant plastic, suitable for harsh environments with strong corrosive chemicals.

Selecting the correct replacement components such as diaphragm chambers, center blocks, and inlet caps is crucial for ensuring the performance and longevity of the diaphragm pump. Users should carefully consider factors such as material, compatibility, and operating environment when choosing these components. Selecting the wrong components can not only affect pump performance but also lead to significant repair and replacement costs in the future.

Hepas offers a wide range of high-quality industrial pump parts that meet the stringent standards of leading brands such as Aro, Sandpiper, and Wilden. Our products, including options for liquid chambers for industrial pumps, ensure the smooth operation of your pumping systems.

With competitive pricing, fast delivery, and a team of experienced technicians, Hepas is your trusted partner.

Contact us for expert advice and support regarding replacement parts for diaphragm pumps. Whether you need to look for replacement parts or a complete air chamber for an industrial pump solution, we are here to help.