When a system underperforms—delivering low airflow or failing to reach the required pressure—the issue is often related to the pump configuration. Many engineers overlook the importance of choosing between parallel and series setups when using a double-head gas diaphragm pump. This mistake can lead to energy waste, premature wear, and unstable performance. As someone deeply involved in micro gas pump design, I’ve seen how critical this decision is, especially in compact and performance-sensitive systems.
A parallel configuration boosts the total flow rate by running both pump heads at the same time, pulling air from a shared inlet and pushing it into a common outlet. On the other hand, a series configuration increases pressure or vacuum by channeling the output of one pump head directly into the other. The right setup depends entirely on whether your system prioritizes flow or pressure.
In this article, I’ll explain the technical differences between these two configurations, when to use each, and how to make the right decision for your application.
What is a Double-Head Gas Diaphragm Pump?
A double-head gas diaphragm pump is a compact, oil-free pneumatic pump equipped with two pumping chambers. These two heads are driven by the same motor, typically working in sync. The pump moves gas by flexing a diaphragm back and forth, creating suction and discharge without contamination.
The beauty of a double-head design lies in its flexibility. We can connect the two pump heads in parallel or series, depending on performance needs. Each setup changes how the system handles gas flow and pressure.
What Is a Parallel Configuration?
In a parallel configuration, both pump heads operate simultaneously, drawing gas from a shared inlet and discharging it through a common outlet. This setup is equivalent to having two pumps working side by side to handle the same task.
Key Advantages of Parallel Configuration:
- Higher Total Flow Rate
Since both heads move gas in parallel, the total flow is approximately the sum of each pump head’s output. - Improved Redundancy
If one pump head fails, the other can continue operating, maintaining partial functionality. - Lower Load Per Head
Distributing the load across two heads reduces mechanical stress and prolongs pump lifespan. - Lower Pressure Build-Up
Because both heads deliver to the same output at the same pressure, the system operates at a moderate pressure level.
Typical Applications:
- Air circulation systems
- Atmospheric gas sampling
- Portable gas transfer equipment
- Gas flushing for environmental enclosures
What Is a Series Configuration?
In a series configuration, the outlet of the first pump head connects directly to the inlet of the second head. This setup allows the pressure or vacuum generated by the first stage to be further boosted by the second, effectively stacking pressure levels.
Key Advantages of Series Configuration:
- Significantly Increased Pressure or Vacuum
By staging the pump heads, the system can achieve much higher pressure differentials than a single-stage setup. - Enhanced Performance in High-Resistance Systems
Useful for overcoming restrictions such as narrow channels, filters, or backpressure. - Compact Alternative to Larger Pumps
Instead of using one large high-pressure pump, two small heads in series offer space and energy efficiency.
Typical Applications:
- Gas leak detection systems
- Fuel cell gas circulation
- Deep vacuum or high-pressure generation in analytical instruments
- Precision pressure control in calibration devices
Key Differences: Diaphragm Gas Pumps In Parallel vs. Series
| Feature | Parallel Configuration | Series Configuration |
|---|---|---|
| Flow Rate | Increased total flow (sum of both heads) | Limited by the slowest stage |
| Pressure/Vacuum | Moderate, consistent | Higher pressure/vacuum through staged compression |
| Fault Tolerance | Higher (redundancy between heads) | Lower (interdependence between stages) |
| Application Focus | High-volume, low-pressure | Low-volume, high-pressure or deep vacuum |
| Control Complexity | Simple | Slightly more complex (requires pressure staging) |
| Noise & Vibration | Balanced | May increase with pressure stage load |
How to Choose the Right Configuration for Your Application
Selecting the correct configuration depends on your application’s core requirements:
- Need Higher Flow Rate?
→ Choose parallel configuration. Ideal for sampling large gas volumes or providing continuous circulation. - Need Higher Pressure or Deeper Vacuum?
→ Go with series configuration. Critical for instruments requiring high differential pressure or precision vacuum control. - Design Constraints?
→ Consider energy consumption, mounting space, and noise. Parallel systems often run cooler and quieter; series systems require careful component matching. - Need Custom Control?
→ Evaluate if independent control of each head is necessary. Asynchronous operation in parallel can optimize energy use, while staged control in series can prevent overloading.
BODENFLO’s Capabilities in Double-Head Pump Design
At BODENFLO, we specialize in the design and manufacturing of double-head gas diaphragm pumps optimized for both parallel and series configurations. Our engineering team collaborates with clients to develop custom pump modules based on specific flow and pressure requirements.
Customization Highlights:
- Support for asynchronous or synchronous head operation
- Low-noise structure with silicone shock absorbers
- Flexible valve configurations for anti-backflow performance
- High-performance brushless or brushed DC motors
- Configurable flow paths for easy integration into closed systems
Whether your goal is to maximize gas flow or achieve deep vacuum in a compact design, BODENFLO’s tailored pump solutions ensure that your product meets performance targets with reliability and efficiency.
Two Popular Double-Head Diaphragm Pumps You Should Know
At BODENFLO, we’ve designed a range of double-head diaphragm pumps to meet various OEM needs. Here are two of our most popular models, widely adopted in gas sampling, environmental detection, and smart pneumatic systems.
Model: BD-05TVB – Compact, High-Performance Dual Head Pump
If you’re working with space-constrained devices but need reliable performance, the BD-05TVB is your go-to solution. This model combines compact size, quiet operation, and long service life with the flexibility to operate in either parallel or series configuration.
Key Specifications:
- Parallel Mode:
- Flow (@0 kPa): 7.2 L/min
- Max Vacuum: -70 kPa
- Max Pressure: 1.5 bar
- Series Mode:
- Flow (@0 kPa): 4.6 L/min
- Max Vacuum: -90 kPa
- Voltage / Power: 12V / 24V; Max 8W
- Motor Type: Brushless DC Motor
- Lifetime: 8,000–10,000 hours
- Size: 76.2 × 32 × 64.3 mm
- Weight: 188g
This pump is ideal for portable gas analyzers, air leak detection tools, or compact medical devices. Thanks to the brushless motor, it offers excellent stability, long life, and low maintenance.
Model: BD-05T0617L – High Flow Industrial-Grade Twin Pump
When your application demands strong suction or powerful air delivery, the BD-05T0617L delivers. Built with a more robust structure and higher-capacity components, this model is perfect for industrial sampling, gas filtration, or pressure simulation systems.
Key Specifications:
- Parallel Mode:
- Flow: 17 L/min
- Max Vacuum: -85 kPa
- Max Pressure: 1.7 bar
- Series Mode:
- Flow: 7 L/min
- Max Vacuum: -95 kPa
- Motor Type: Brushed DC Motor
- Max Power: 14W
- Lifetime: 4,000–6,000 hours
- Size: 197 × 46 × 77 mm
- Weight: 943g
This model is particularly suited for large-volume sampling equipment, continuous circulation systems, and equipment requiring high negative pressure. It balances cost-efficiency and reliable performance for mid- to high-demand applications.
Conclusion
Double-head gas diaphragm pumps offer unmatched flexibility in gas transfer systems. Understanding the difference between parallel and series configurations helps ensure optimal system performance, efficiency, and longevity.
If you’re developing an OEM product that requires precise control of flow or pressure in a compact footprint, talk to BODENFLO. Our technical team will work closely with you to configure the right double-head gas diaphragm pump solution — whether it’s flow-first, pressure-first, or something in between.
📩 Contact us at info@bodenpump.com to start your project consultation today.
