The Hilintec D31 low pulsation pump Series is a next-generation,  diaphragm gas pump designed for analytical instruments, medical devices, and environmental monitoring. Unlike traditional 1-chamber or 2-chamber pumps, the D31 features a unique 5-chamber linkage structure that delivers an exceptionally smooth, pulse-free flow. It supports both vacuum and pressure operation, offers PWM speed control and FG speed feedback, and delivers high flow in a compact footprint. Ideal for instruments requiring steady, pulse‑free gas delivery with long‑term durability.

Ultra‑Low Pulsation Flow Output

The D31 series adopts a proprietary 5‑chamber linkage diaphragm structure that significantly evens out instantaneous flow fluctuations. Unlike standard single‑chamber diaphragm pumps with obvious periodic pulsation, D31 provides near‑smooth gas delivery. This low‑pulse characteristic greatly simplifies gas circuit design, reduces requirements for buffer tanks or stabilizers, and improves the stability and accuracy of gas sensors and analytical systems.

In the field of dust particle counter applications, 2.83LPM or 0.1 CFM  rotary vane sampling air pumps are widely used due to their low pulsation characteristics.However, the vane sampling pump has a short life and high cost due to its wear characteristics.The five pump chambers inside the D31 work together to achieve a low pulsation output similar to that of a rotary vane sampling air pump, while its low-wear diaphragm gas pump characteristics can achieve much lower costs and longer operating life than its competitors, making it very suitable for replacing sampling pumps in low pulsation scenarios.

You can also refer to our  Hilintec Pulsation Elimination Technology to get more information。

Long Service Life & 24/7 Continuous Operation

Equipped with a high‑performance brushless DC motor (BLDC) and wear‑resistant wetted components, the D31 supports heavy‑load continuous running. The motor life reaches up to 18,000 hours, and the diaphragm gas pump full‑load life up to 8,000 hours under laboratory test conditions. It is designed for stable, long‑term use in industrial instruments, medical devices, and online monitoring equipment without frequent replacement or maintenance.

High Flow Output in an Ultra-Compact Footprint

The D31M delivers 4.0 L/min average flow while measuring only 80.5 × 40.5 × 39.5 mm and weighing approximately 150 grams. The D31Q delivers 3.5 L/min average flow with slightly larger dimensions at 95.5 × 40.5 × 39.5 mm and weighing approximately 190 grams. Both variants offer excellent flow-to-size ratios, with the D31M prioritizing maximum flow and the D31Q prioritizing quiet environment.

It has five pump chambers in a very small structure. If you need a more reliable diaphragm gas pump, you can refer to the C26 mini pump model.

 

Speed Control Function

The flow(BLDC type) can be changed by adjusting the motor speed of the diaphragm gas pump (by adjusting the PWM duty cycle).

 

Dual Vacuum & Pressure Function

Each D31 diaphragm gas pump integrates both vacuum suction and positive pressure output in one unit. It can achieve a relative vacuum of ≥-35 kPa and output pressure up to 55 kPa (standard/premium versions). This dual function reduces the number of diaphragm gas pumps in the system, lowers overall cost, saves installation space, and simplifies piping and control logic.

Speed Feedback Signal

The brushless motor type can know the high and low speed of the diaphragm gas pump through the speed feedback signal. From this, the operating state of the pump can be known, which is convenient for realizing closed-loop control and making the system more intelligent

 

Industrial-grade Reliability for Low Pulsation Pump

In response to industrial-grade reliability requirements, we have designed a special test process for possible load conditions. Therefore, no matter what load the product actually works under, its actual service life can reach and exceed its nominal service life. If the actual working load is less than the nominal maximum load, its life can be further extended. Therefore tt can operate without stopping for a long time under the maximum load. The product has passed the life test under the maximum load, and can promise to reach the nominal life under various loads.