The ZK series vacuum and low-positive-pressure dual-use solenoid valve (nominal diameter ranging from DN2.5 to DN100) is a high-airtightness, bidirectional pressure-resistant fluid control device specially designed and developed for industrial vacuum systems, negative-pressure suction networks, vacuum packaging, and atmospheric/low-positive-pressure gas-liquid circulation pipelines. As a core execution element in vacuum engineering and scientific instrument control loops, this series features comprehensive structural optimization targeting extreme negative pressure vacuum conditions from -1bar to 0bar and conventional low-positive-pressure conditions from 0bar to 1bar. It focuses on solving technical industry difficulties where ordinary industrial solenoid valves are highly prone to reverse suction leakage under vacuum negative pressure, diaphragms being sucked flat in reverse, and the inability to actuate properly under completely zero pressure differential environments. The series adopts direct acting drive for small-bore valves and semi-direct acting linkage drive for large-bore valves. It offers multiple premium valve body materials including brass and SS304 stainless steel (where JF represents high-strength flange versions), and interfaces cover G/NPT thread and standard flanges, widely matching vacuum smelting, medical negative pressure suction, semiconductor vacuum equipment, food packaging machinery, and low-pressure fluid environmental treatment core industrial fields.
This series of valves utilizes pure direct acting or semi-direct acting mechanisms based on the bore size, belonging to the normally closed automatic valve type. Its core advantage lies in the fact that its opening and closing are completely independent of the medium pressure differential inside the pipeline, possessing excellent bidirectional sealing performance. When the electromagnetic coil is de-energized, the high-elasticity return spring applies direct force through the main valve shaft, driving the specialized vacuum-type sealing core downward rapidly to press it firmly against the main valve seat. Whether the upstream end of the valve is in an absolute vacuum state of -1bar or the downstream end has a slight positive pressure within 1bar, the specialized dynamic sealing pair structure can rigidly counteract interference brought by the bidirectional pressure differential, achieving tight dead shut-off with an ultra-low leakage rate.
When the electromagnetic coil is energized, a specially customized heavy-duty electromagnetic assembly generates a powerful electromagnetic attraction force. For small-bore direct acting valves (such as ZK-025, etc.), the electromagnetic force directly overcomes the spring force to lift the valve core, achieving microsecond-level switching. For large-bore semi-direct acting valves (such as DN15~100 specifications), the moving iron core first opens the pilot hole to balance the cavity pressure through an internally specialized back-kick linkage structure, and then rigidly lifts the entire main valve core assembly. Even in an extreme condition where the system is in an absolute pure vacuum state without any pressure differential, the valve can be thoroughly pulled open by the mechanical linkage, the main valve port opens instantly, and the medium restores large-flow unhindered passage. Once the coil is de-energized, the mechanical structure resets at high speed within milliseconds, perfectly eliminating the common industry problem where traditional valves actuate sluggishly or fail to actuate under negative pressure vacuum conditions.
Product Image:ZK Vacuum Solenoid Valve