I. Industry Challenges: The Three Major Hazards of Sliding Pump Operation Under CAFS High-Pressure Conditions

In Class A compressed air foam fire suppression systems (CAFS) for fire trucks, the foam liquid pump serves as the "precision metering heart" for proportional mixing. For decades, domestic fire truck manufacturers have predominantly employed vane pumps to drive the delivery of Class A foam liquid. However, as urban primary fire trucks increasingly demand higher operating pressures and precise micro-dosing capabilities, the technical limitations of vane pumps have become increasingly apparent, even posing fracture risks under high-load conditions.

Hidden Risk 1: Insufficient Resolution: Coarse "Stage-Based" Measurement

The vane pump discharges fluid by utilizing the volume change created by the eccentric rotor and a small number of vanes (typically 8–12). Due to the limited number of vanes, the displacement resolution per revolution is low; consequently, under the CAFS system's requirement for a micro-mixing ratio of 0.1%–1.0%, continuous linear flow regulation cannot be achieved, resulting in a distinct "stepwise" flow output. When the flow rate in the main water circuit changes, the foam liquid supply cannot respond accurately and promptly, causing the mixing ratio to fluctuate—excessive concentration leads to foam liquid waste and equipment corrosion, while insufficient concentration results in a sharp decline in fire suppression efficiency.

Hidden Risk 2. Micro-flow Loss of Control: Low-Speed Pulsations and Internal Leakage

In actual firefighting operations, the flow rate ratio ranges from micro-water spraying (requiring 0.18 L/min of foam solution) to full main nozzle operation (requiring 10 L/min), exceeding 55:1. Under low-speed conditions, the insufficient centrifugal force of the vane pump reduces contact pressure and causes a sharp increase in internal leakage; simultaneously, flow pulsations caused by the limited number of vanes are amplified at low rotational speeds. The system must resort to complex buffer tanks and frequent manual valve adjustments to compensate, which not only increases pipeline dead weight but also slows response speed.

Hidden Risk 3: Wear and Fracture Risk Under High Load – The Hidden Bomb of Fire Trucks

II. Technological Breakthrough: JONSN Brand Multi-tooth High-Resolution Magnetic Gear Pump

The JONSN brand's multi-tooth high-resolution magnetic gear pump has developed the MRE series miniature magnetic gear pumps specifically for the extreme operating conditions of fire truck CAFS systems. This innovation goes beyond merely "replacing blades with teeth"; it fundamentally redefines the delivery of Class A foam liquid—from fluid metering principles to structural reliability—completely eliminating wear and fracture risks under high loads.

Core Design Philosophy: Conquer the wide adjustment ratio with "resolution," and replace "sliding friction" with "engrained transmission." 

Technical Analysis: Why Does "High Number of Teeth + Engagement Transmission" Deliver a Revolutionary Experience?

1. Enhanced physical resolution – From "stepwise" to "continuous": The JONSN pump employs a precision multi-tooth gear pair (with a tooth count significantly higher than that of conventional gear pumps). At the same displacement, each full rotation of the gears divides the discharged liquid into more numerous and finer individual units. This directly results in:

2. Meshing transmission replaces sliding friction—completely eliminating the risk of fracture under high loads. This represents the most fundamental structural difference between JONSN and vane pumps:

3. Zero-leakage and high-vacuum performance driven by magnetic force: Utilizing a magnetic coupling drive combined with an isolation sleeve design, the dynamic shaft seal is completely eliminated.The foam liquid, a medium with high permeability and containing fluorinated surfactants, has no leakage pathways. Meanwhile, its excellent sealing performance ensures an exceptionally high inlet vacuum (-0.095 MPa), enabling instant self-suction even when the foam liquid tank operates under atmospheric pressure with an open supply system, thereby completely eliminating cavitation.

4. Two-stage precision structure + imported PEEK gears

III. Practical Verification: A Fire Truck Manufacturing company

Customer Background

A Fire Truck Manufacturing company is a leading domestic enterprise specializing in the research, development, and production of high-end firefighting equipment. Its urban main battle fire trucks and multi-functional emergency rescue vehicles are equipped with Class A compressed air foam systems (CAFS), which impose extremely stringent requirements on the precision, volume, and reliability of foam liquid pumps.

Key pain points of the original solution: The slide pump's "insufficient performance" and "potential fracture risk"

Prior to adopting the JONSN solution, a certain urban main battle fire truck model manufactured by a fire truck production company was equipped with an imported brand vane pump.

· Most critical: Fracture risk under high loads: During a three-hour high-intensity firefighting drill, the vane pump exhibited abnormal noise after operating for 2.5 hours at 14 bar. Disassembly revealed a fatigue crack at the base of one vane, nearly causing fracture and seizure. This incident prompted the technical department of a fire truck manufacturing company to resolve to identify a more reliable alternative solution.

JONSN Solution: MRE Series Micro Magnetic Gear Pump (Custom Version for Fire Vehicles)

In response to the extreme operating conditions specified by a fire truck manufacturing company, JONSN conducted specialized on-board adaptations:

Advantages of the loading layout

· Physical specifications: The pump + servo motor assembly has an axial length <343 mm and a radial profile <φ163 mm, directly integrated into the valve assembly plate at the bottom of the foam tank.

· Weight optimization: The stainless steel pump body combined with a lightweight servo motor reduces the overall assembly weight by approximately 40% compared to the original vane pump design.

· Simplified piping: The absence of pulsation characteristics eliminates the need for pulse dampers and buffer tanks, reduces piping connections by six, decreases the system dead volume, and facilitates easier fluid replacement and cleaning.

· Reliability has undergone a transformation: from concerns about slide fracture under high loads to tooth surfaces remaining as pristine after 500 hours of high-pressure operation, marking a significant improvement in overall vehicle reliability.

IV. Focus on fire truck vehicles and deepen CAFS applications

JONSN Fluid Technology fully recognizes that fire trucks are not industrial sites but mobile platforms delivering high-pressure, high-precision, and highly reliable fluid performance. Instead of merely repackaging industrial pumps, we have conducted comprehensive customization tailored to the specific requirements of fire trucks.

V. Conclusion: Equipping every fire truck with a precise and reliable "foam heart"

From urban main battle fire trucks produced by a fire truck manufacturing company to various high-end firefighting equipment soon to be deployed, the JONSN miniature magnetic gear pump demonstrates that the delivery of Class A foam liquid can be both precise and reliable, compact yet durable—and most importantly, completely eliminates the risk of wear and fracture under heavy loads.

When a fire breaks out and firefighters press the water discharge button, what they need behind the scenes is a foam liquid pump capable of instant response across temperatures ranging from-40°C to +60°C, precise metering from 0.18 L/min to 10 L/min, and complete resistance to wear, breakage, and leakage under 14 bar of high pressure. JONSN is committed to safeguarding every mission with micron-level precision and rock-solid reliability.