A 2-way normally closed (N/C) solenoid valve is an electromechanical control device designed to isolate or block flow path lines dynamically when de-energized. The designation "normally closed" represents a fail-safe state: without an electrical signal input, the internal spring mechanism maintains a physical seal against the seating orifice, preventing media bypass. When current is introduced to the solenoid coil, a concentrated magnetic field moves the internal armature upward against the spring force, opening the pathway.
Ideal for low flow rates and systems operating at zero differential pressure. The electromagnetic force acts directly on the valve seal, pulling it off the seat. Because it does not rely on line pressure to function, it provides extremely reliable cycles for domestic gas manifolds and laboratory operations.
For high-pressure pipelines or massive flow diameters, pilot-operated valves utilize the pressure differential of the system fluid. The coil control triggers a small pilot opening which relieves pressure on top of the internal diaphragm, allowing the line fluid to lift the main seal. Crucial for heavy chemical processing lines and municipal mains.
High-quality construction relies on premium sealing compounds chosen specifically for the chemical compatibility of the target medium. For combustible gaseous fuels like methane (natural gas), LPG (propane/butane), and coal gas, Nitrile Butadiene Rubber (NBR) or Viton (FKM) diaphragms are used. These elastomers prevent micro-leakage and maintain flexible sealing limits under extremes of -20°C to +60°C.
Founded in 2003, Xinhaosi is one of the most influential and trusted brands in the global gas safety industry. Over the past two decades, we have steadily built a robust and comprehensive production and service system, which integrates cutting-edge R&D, intelligent manufacturing with advanced automation equipment, digital marketing across global channels, professional after-sales support with an experienced technician team, flexible OEM/ODM services, as well as CNAS-Accredited laboratory calibration services that meet international standards.
Our diversified product portfolio covers industrial & residential gas detection & alarm systems, industrial & household gas solenoid valves, and urban gas pipeline network monitoring systems—all engineered to adapt to complex working environments and strict safety requirements. We produce and sell tens of millions of units annually, catering to a wide range of industries that demand reliable gas detection solutions, including oil & gas exploration and production, petrochemicals, urban gas distribution, automotive manufacturing, pharmaceuticals, new energy, steel production, and beverage processing.
Guided by the core mission of “Making Gas Safety Accessible Everywhere,” we consistently deliver high-performance, reliable products and customized solutions tailored to each client’s unique needs. Every item we manufacture undergoes rigorous quality control tests, and every service we provide is backed by our professional technical team, fully embodying our unwavering commitment to safeguarding gas safety across both industrial workplaces and residential environments, and striving to build a safer world with sustainable gas safety technologies.
Adhering to ISO9001 quality management system standards, Xinhaosi's core products have obtained a full range of authoritative certifications, including national compulsory Products Certification, explosion-proof certification, fire product certification, CPA measurement instrument type approval certificate, and international approvals such as CE and SIL. Additionally, Xinhaosi holds honors such as "National Quality Integrity Benchmark Enterprise" and "National Quality Leading Enterprise in the Gas Alarm Industry," is a member of the China Fire Protection Association, and acts as the main drafting organization for the national standard of solenoid valves, further confirming its industry influence and reputation.
In the field of intellectual property, Xinhaosi has built a robust innovation system with over 50 patents and software copyrights. These patents cover core technological areas, including a graphical monitoring system for gas detection and alarm, which enables predictive maintenance based on historical data to reduce equipment failure rates by over 30%, and a solenoid valve with flow monitoring functionality that integrates flow detection and alarm capabilities. The company also pioneered China's first networked bus-type gas leakage monitoring system and the only maximum-point gas leakage monitoring system certified by the Ministry of Public Security, demonstrating its leading position in cutting-edge technological research.
Our in-house laboratory is accredited by the China National Accreditation Service for Conformity Assessment (CNAS), recognized both domestically and internationally under the ILAC-MRA framework. It operates in accordance with ISO/IEC 17025, the international standard for testing and calibration laboratories. It provides reliable and traceable testing services for gas detection and alarm products, solenoid valves, and related safety equipment. Test reports issued by the CNAS-accredited laboratory are widely accepted by regulatory authorities, certification bodies, and customers in China and overseas, helping to ensure product quality, safety compliance, and market access.
Start Up Phase
● Established in Apr. 17th, 2003.
● Launched the 1st generation of gas leak alarm & fire fighting products.
Initial Scale Achievement
● Started gas safety valve production.
● Expanding on OEM business.
● Moved to the office building in Longtan industrial park.
Rapid Growth
● 10 millions pcs gas detector sales achieved.
● Moved into Chengdu factory building.
● Completed sales & service network across China.
● Launched the fire power monitoring system products.
Leading Up
● Self-developed IoT platform launched.
● Launched fire automatic alarm, emergency lighting, and evacuation systems.
● Obtained high-tech enterprise certificate.
● Qualified official supplier of China’s top 5 gas suppliers.
Steady Development
● Started Deyang factory construction.
● Established the Petrochemical & International business Division.
● Awarded the title of Sichuan Provincial Technology Center.
Embrace the Future
● Deyang factory construction completed and operation started.
● Launched urban gas pipeline network monitoring products.
● Launched wireless detection products.
● Launched AI safety valve products.
Modern industrial processing systems demand absolute safety coordination between active detection devices and electromechanical control components. Our 2-way normally closed solenoid valves function as the primary shut-off mechanism in safety-instrumented systems (SIS). In environments such as chemical plants, metallurgy factories, and municipal gas transmission lines, the combination of combustible gas detectors and normally closed valves establishes a highly secure safety loop.
In standard operations, a controller delivers continuous electrical power to the solenoid valve coil, keeping it open to allow gas to flow. When a gas leak is detected or a system power outage occurs, the power supply to the coil is immediately cut. This triggers the valve's mechanical spring, causing it to shut off flow in milliseconds, isolating the hazard area and preventing potential fires or explosions.
Municipal gas networks employ normally closed solenoid systems linked to centralized IoT control panels. By monitoring pressure differentials and localized seismic sensors, operators can rapidly isolate segments of the utility grid remotely, preventing hazardous conditions across residential and commercial sectors.
Industrial procurement departments globally require complete compliance with international standards before adding manufacturers to their approved vendor list (AVL). When sourcing electromagnetic control components, certifications confirm structural reliability, chemical safety, and explosion-proof capability.
Key standards for global sourcing include:
To support global supply chains, our production lines offer flexible OEM/ODM modifications, custom voltage coils, customized body structures (brass, aluminum, or stainless steel), and localized packaging that complies with regional distribution laws.
The traditional solenoid valve is evolving from a passive mechanical component into an active, self-monitoring node within the Industrial Internet of Things (IIoT). The technical roadmap for our safety solutions focuses on integrating diagnostics, low power usage, and active feedback loops.
By constantly monitoring coil temperature, electrical current, and cycle counts, our next-generation valves detect magnetic degradation before a failure occurs. This active diagnostics approach supports predictive maintenance, reducing unscheduled facility shutdowns.
Standard solenoid valves consume continuous power to maintain the open state. Our advanced controllers utilize a dual-stage driver: applying a high current pulse to actuate the valve, then dropping to a low-power hold state. This design reduces energy consumption and thermal output by up to 70%.
