Dongfeng KL Hand controlled valve 3517910-TR900 for sale

As a core component of the Dongfeng KL’s auxiliary brake system, this hand controlled valve delivers precise air pressure regulation to ensure safe and responsive braking. It features a two-stage pressure adjustment design with a working pressure range of 0-1MPa, allowing drivers to control the parking brake and emergency brake with graded force. The valve’s internal pressure relief valve maintains a stable output pressure (fluctuation ≤ ±0.02MPa) even when the truck’s main air reservoir pressure varies (8-10bar), preventing over-braking or insufficient braking force. Additionally, it has a quick-response time (≤ 0.3 seconds from lever operation to pressure output), ensuring timely activation of the brake system—critical for emergency stops or parking on sloped roads (up to 15° incline) with heavy loads (max 49 tons for Dongfeng KL)

Built to withstand the harsh operating conditions of heavy-duty trucks, the valve’s body is crafted from high-strength aluminum alloy (ADC12) with a hard anodized surface treatment (coating thickness 15-20μm). This material combination offers exceptional corrosion resistance (passing 480-hour salt spray testing without rust) and impact resistance (able to withstand 100N lateral force without deformation). The internal sealing components use nitrile rubber (NBR) O-rings and polyurethane (PU) diaphragms—both resistant to high temperatures (up to 120℃) and oil contamination, ensuring long-term air tightness (air leakage rate ≤ 1mL/min at 1MPa pressure). The valve’s control lever is made of reinforced nylon (PA6+30% glass fiber), providing excellent wear resistance (service life of 50,000+ lever operations) and a comfortable grip for drivers

Safety is integrated into every aspect of this hand controlled valve’s design. It includes a mechanical locking mechanism for the parking brake function—when the lever is pulled to the “park” position, a spring-loaded pin automatically locks the lever in place, preventing accidental release due to road vibration or driver error. The valve also has a pressure loss warning function: if the air pressure in the brake system drops below 6bar, a built-in pressure switch triggers the truck’s dashboard warning light, alerting the driver to potential brake system failures. Additionally, the valve complies with China’s GB 12676-2014 “Commercial Vehicle Brake System Technical Requirements” and European ECE R13 standards, ensuring it meets global safety criteria for braking performance, including emergency brake efficiency (≥ 55% deceleration) and parking brake holding force (≥ 30% of vehicle weight)

Installing this hand controlled valve is simple and efficient, even for on-site maintenance. It comes with all necessary mounting hardware (4 M8×20 hexagon bolts, 4 flat washers, and 4 lock washers) and a detailed installation manual with dimensional diagrams (overall size: 180mm × 105mm × 85mm) to guide positioning. The valve’s air ports are clearly marked (“IN” for air inlet, “OUT1” for parking brake, “OUT2” for emergency brake) to avoid connection errors, and the control lever’s rotation angle (120°) is pre-calibrated to match the Dongfeng KL’s driver seat position, ensuring ergonomic operation. For maintenance, the valve features a detachable top cover—allowing easy access to internal components (e.g., O-rings, diaphragms) for inspection or replacement without removing the entire valve from the truck. This design reduces maintenance time (≤ 30 minutes for routine checks) and lowers long-term repair costs for fleet operators