The EX Series Pneumatic Double Diaphragm Pump is specifically designed for transporting high-viscosity, abrasive or shear-sensitive fluids from tanks or flange-mounted storage tanks. It is directly installed on the tank opening or the tank flange, replacing the cumbersome method of tipping heavy tanks, and smoothly delivers ink, adhesives, paints, slurries or emulsions into the pipeline, avoiding spills and waste from the bottom of the tank.

The Core Difference from Ordinary Diaphragm Pumps

Ordinary pneumatic diaphragm pumps are mostly installed on walls or carts and require a long suction tube to draw liquid from the tank. The EX Series is directly placed on the tank or tank flange, bringing about three significant changes:

No need to estimate suction height: The pump’s suction inlet is inserted into the liquid surface through the tank opening, self-suction is rapid, and the liquid is emptied more thoroughly, unaffected by the influence of long gravity tubes.

Small footprint: No need for carts, bases or long straws. This makes it particularly advantageous in cramped mixing rooms.

Dead volume is small: The fluid path is short and there are few joints, resulting in a significant reduction in residual product remaining in the pump during shift changes.

Key features affecting daily operations

No stalling of pneumatic motors: Even under low pressure or slow operation, the valve can reliably change direction; if the motor stalls under back pressure, it will force the production line to manually reset.

Material compatibility: The wet end (pump body, diaphragm, ball valve, valve seat) must match the fluid. Polypropylene and acetal are suitable for water-based and mild solvents; stainless steel or PVDF can handle corrosive chemicals. A variety of material combinations enable the pump to adapt to the fluid, rather than the other way around.

All-plastic pneumatic motor option: Some models feature an all-plastic pneumatic component, suitable for areas prone to water flow or corrosive environments, preventing the oxidation and flaking of cast aluminum.

Pulsation damper compatibility: The dual diaphragm pump naturally generates pressure pulsations, and an external damper can smooth the output to meet the stable pressure requirements of downstream nozzles or filling valves.

Tank pump vs Flange-mounted pump

Traditional tank pumps are slender submerged pipes, while the EX series is a standard-sized diaphragm pump equipped with a pipe inserted into the tank opening, or a flange-mounted version directly fixed to the tank flange. Therefore, it can pump high-viscosity materials much heavier than thin-tube centrifugal pumps. The pneumatic motor is located above the tank, and the exhaust is away from the fluid – this is crucial when handling flammable substances or in explosion-proof areas.

When installing flanges, the pump is fixed to the tank flange, the suction port is immersed in the liquid surface, and it is commonly used in storage tanks, mixing vessels, and circulation loops. The pump body is fixed, and the discharge pipeline transports the fluid to the usage point.

Selection tips

The following list can be prepared before purchasing to avoid repeated work:

1. Define the fluid: name, viscosity under the pumping temperature, solid content. Abrasive slurries require hardened valve seats, and dilute solvents require tight ball valve seals.

2. Determine the flow and outlet pressure: reverse-engineer from the downstream equipment. For example, if a spray gun needs 8L/min at 3bar, clearly define the air pressure requirement for this working condition.

3. Check the tank/skin interface: the tank opening size, flange bolt hole spacing, and thread standard must match; otherwise, a adapter is needed and the construction schedule will be delayed.

4. Evaluate the environment: indoor/outdoor, temperature range, whether rinsing is required, electrical explosion-proof grade, all affect the pump body and pneumatic motor material.

5. Synchronize the selection of accessories: brackets, pulsation dampers, pressure gauges, pressure regulating kits, connection strips, etc. should be included in the same list, not purchased later, as these determine whether the first-day operation is smooth.

Beyond efficiency – value in safety

In terms of safety, pneumatic pumps eliminate the risk of electrical sparks from the motor in the solvent area; the pump body can be grounded, the flow path is conductive, and static electricity can be dissipated – this is no small matter for managers who have experienced fire accidents.

In terms of maintenance, self-priming capability, no leakage when emptying the tank body, and the ability to replace wear parts without completely disassembling mean less downtime. At the same time, it reduces the need to tip over heavy tanks, lowers the risk of employees’ back and waist strain and chemical leakage.