Driven by large AI models, computing power demand has exploded. The power density of a single cabinet has surged from 10 kW to 40–100 kW, pushing traditional air cooling to its heat dissipation limit. Cold plate liquid cooling has become the mainstream thermal management solution for data centers. As the core of liquid cooling systems, the CDU (Coolant Distribution Unit) performs heat exchange and flow allocation between the primary loop (chilled water) and the secondary loop (deionized coolant).
During long-term circulation, the coolant requires continuous pressure-stabilized water replenishment, as well as accurate dosing of corrosion inhibitors, biocides and pH regulators to maintain water quality. Acting as the heart of the CDU, pumps directly determine the thermal stability and service life of the cooling system via their precision, reliability and chemical resistance.
The JONSN MR Series micro magnetic gear pumps deliver pulse-free positive displacement output, fully magnetic leak-free sealing and chemically inert construction materials. They provide a complete fluid solution for CDU liquid cooling, covering main circulation and water treatment applications.
The CDU primary loop transports chilled water from chillers to plate heat exchangers, while the secondary loop distributes deionized coolant to cold plates in each cabinet. A flow fluctuation of ±3% will shift chip junction temperature by 3–5°C, triggering frequency reduction protection and severe computing performance loss.
Centrifugal pumps suffer sharply reduced efficiency and high cavitation risk under low-flow conditions, and mechanical seals present increasing leakage risks over years of operation. For primary loops with ethylene glycol antifreeze, pump seals must additionally resist swelling from glycol exposure.
Closed liquid cooling systems experience coolant volume shrinkage due to minor internal leakage and temperature changes. Pressure-stabilized makeup units are required to maintain system pressure between 1.5–2.5 bar. Typical makeup flow rates stand at only 0.1–2 L/h. Conventional makeup pumps start and stop frequently under such tiny flow rates, generating heavy pressure shocks and shortening pump service life.
Makeup water must be deionized (conductivity < 1 μS/cm). Metal ion leaching from pumps will directly raise coolant conductivity, breaking insulation and creating safety hazards from leakage current.
During prolonged coolant circulation, continuous monitoring and dosing of corrosion inhibitors (e.g. BTA benzotriazole), biocides (isothiazolinone) and pH buffers are mandatory, with typical dosing concentrations ranging from 10–100 ppm. PPM-level micro-metering demands consistent ±2% accuracy even at high dilution ratios. Over-dosing wastes chemicals and causes coolant foaming; insufficient dosing leads to pipeline corrosion and microbial growth.
Traditional metering pumps lose accuracy below 10 ppm and exhibit poor resistance to chlorine-containing biocides.
The MRB Series (400–4,800 ml/min) and MRC Series (0.8–14 L/min) feature pulse-free positive displacement output for secondary loop coolant circulation. Flow remains unaffected by variations in system backpressure, limiting chip junction temperature fluctuation to less than ±1°C. Pump bodies withstand 4–6 MPa pressure, suitable for long pipeline transport in large-scale data centers.
The MRE Series (4–48 L/min) handles high-flow primary loop chilled water and ethylene glycol mixtures. PEEK + ceramic gear pairs offer complete inertness to glycol media, paired with fully magnetic leak-free sealing to eliminate short-circuit risks to servers caused by liquid dripping.
Secondary loop: MRB (0.4–4.8 L/min) / MRC (0.8–14 L/min), pulse-free operation, junction temperature fluctuation ±1°C
Primary loop: MRE (4–48 L/min), glycol-resistant inert construction, 4–6 MPa pressure resistance
Sealing: Fully magnetic zero-leak design, eliminates dripping-induced short-circuit hazards
The MPG Series micro gear pumps (displacement: 40–80 μl/rev, flow rate: 1–280 ml/min) deliver continuous pulse-free micro-dosing, replacing frequent start-stop cycles of conventional makeup pumps. System pressure stays steady at 1.5–2.5 bar without hydraulic shock, extending pump service life to 20,000 hours.
Flow paths constructed from PEEK and zirconia ceramic eliminate metal ion leaching entirely, keeping coolant conductivity below 1 μS/cm after makeup to meet leakage current safety compliance. Fully magnetic sealing prevents deionized water spillage and preserves data center cleanliness.
Makeup mode: Continuous pulse-free micro-injection, no pressure shock, 20,000-hour pump lifespan
Water quality assurance: PEEK + ceramic construction with zero metal ion leaching, conductivity < 1 μS/cm
Sealing: Fully magnetic sealing, zero deionized water leakage
The 40 μl/rev displacement MPG Series enables continuous PPM-level dosing of corrosion inhibitors, biocides and pH buffers, with concentration control deviation below ±2% relative to total coolant volume — far superior to the industry typical ±10% accuracy of conventional metering pumps.
PEEK construction paired with perfluoroether O-rings delivers outstanding chemical resistance to BTA inhibitors, isothiazolinone biocides and acid-base buffers, resisting swelling and corrosion over long-term operation. Linked to online conductivity, pH and ORP sensor signals, pump flow can be automatically closed-loop regulated to realize fully unattended automated coolant water quality management.
Metering accuracy: 10–100 ppm dosing with deviation < ±2%, outperforming standard metering pumps (±10%)
Chemical compatibility: Stable against BTA, isothiazolinone and acid-base buffers; perfluoroether seals resist swelling
Closed-loop linkage: Flow auto-adjustment triggered by pH / conductivity / ORP sensor signals
CDU Fluid Circuit Section | Typical Flow & Parameters | Recommended Series | Core Advantages |
Secondary Loop Coolant Circulation | 0.4–14 L/min | MRB / MRC | Pulse-free flow, ±1°C junction temperature fluctuation, 6 MPa pressure resistance |
Primary Loop Chilled Water / Ethylene Glycol | 4–48 L/min | MRE | Glycol-inert construction, 4 MPa pressure resistance, zero leakage |
Deionized Water Pressure-Stabilized Makeup | 0.1–2 L/h | MPG | Pulse-free micro-flow, zero metal ion leaching, conductivity < 1 µS/cm |
Corrosion Inhibitor & Biocide Dosing | 10–100 ppm | MPG | < ±2% dosing deviation, automatic closed-loop regulation via sensors |
Online pH Buffer Dosing | 5–50 ppm | MPG | Perfluoroether seals, alternating acid & alkali resistance |
A unified product portfolio including MPG / MRB / MRC / MRE covers all fluid circuit functions of CDUs, from secondary main circulation and pressure-stabilized makeup to PPM-level water treatment chemical dosing. Data center cooling system integrators can complete full pump selection with a single supplier.
Pulse-free positive displacement output delivers absolutely stable secondary loop coolant flow, restricting chip junction temperature variation within ±1°C. Periodic frequency throttling caused by flow pulsation is eliminated, enabling continuous full-load computing performance for AI training tasks.
Fully inert flow channels made of PEEK and zirconia ceramic release no metal ions during deionized water makeup and circulation. Coolant conductivity remains below 1 μS/cm, meeting insulation safety standards for cold plate and immersion liquid cooling.
Precise PPM dosing of corrosion inhibitors, biocides and pH buffers allows on-site coolant recirculation for over 5 years without full tank replacement. Chemical consumption drops by 30%, alongside drastically reduced waste liquid treatment frequency and costs.
Fully magnetic drive zero-leak design withstands 4–6 MPa pressure to suit long pipeline circulation. No mechanical seal wear or dripping fundamentally eliminates catastrophic server circuit short-circuit risks caused by coolant leakage.
PEEK + zirconia ceramic sliding bearings paired with full magnetic drive eliminate consumable wear parts. Only routine inspections are required over the 5-year service cycle of data centers, with no pump body or seal replacement needed — perfectly matching unattended computer room operation modes.
