SSDJ-FZ-*F/C-RQZ Gas Safety Cut-off Valve

SSDJ-FZ-*F/C-RQZ series gas safety shut-off valve is installed in the gas transmission and distribution system, and is provide with the function of monitoring gas pressure over pressure (or pressure loss) cut off (manual reset) .

It makes use of the pressure of pipe network and no additional power is required,and characterized by high precision of operation, and maintain and can worknormally in dirty gas madium, when regulator outlet pressure is higher thana ceratin set value due to system failure, the cut-off valve can quickly cut off the gas source to ensure safe use of gas.

Applicable medium

Natural gas, coal gas, liquefied petroleum gas, gas and other non corrosive gases.

High precision of operation, quick response, use of the pipe net workpressure without additional power: super pressure, is overpressure automatic cut-off; easy installation and debugging, easy to operate and maintain, working environment. can worknormally in dirty gas medium.

The cut-off valve adopts the fifth generation cut-off mechanism; this mechanism is in the form of trip brake release. The main design is that the cut-off membrane and the sliding mechanism are separated, and the sliding mechanism and the tripping mechanism are integrated.

When the sliding mechanism and the tripping mechanism are pushed by the membrane, , causing the sliding mechanism to produce a displacement and then the tripping mechanism breaks away from the valve stem fastening groove. The valve stem is driven by the cutting spring to complete the cutting off overpressure release function.

This structure combines high response sensitivity and the overall design structure is more reasonable to cut off the total process. Safety shut-off valve cutting pressure accuracy AG2.5; response time ≤1s;

Working pressure range:≤6.4MPa

Operating pressure range: 0.005MPa-1.6MPa

Operating temperature: -20°C〜+60°C

Series specification: DN50、DN80、DN100、DN150、DN200、DN250, DN300

Connection mode: Flange Connect PNI.6MPa HG/T20592-2009

How to tell if a gas valve is open or closed?

Determining whether a gas valve is open or closed is an essential safety and operational check in any gas system. Gas valves control the flow of natural gas, LPG, or other flammable gases, and knowing their status prevents accidents, leaks, or system malfunctions.

Most gas valves have visual indicators that show their position. For ball valves, the handle position is key: when the handle is aligned parallel with the pipe, the valve is open, allowing gas to flow. When the handle is perpendicular to the pipe, the valve is closed, stopping the flow. Gate valves and globe valves typically have a rising stem; if the stem is fully raised, the valve is open, and if it is fully lowered, the valve is closed. Some valves also feature marked indicators, arrows, or a “OPEN/CLOSE” label to provide a clear visual reference.

For valves without clear visual indicators, pressure gauges can help determine the status. By comparing upstream and downstream pressures, one can infer whether gas is flowing. If the downstream pressure is zero or significantly lower than the supply pressure, the valve is likely closed. Conversely, similar pressures indicate an open valve.

In certain modern or industrial systems, valves may have electronic position sensors or switches that provide remote indication. These devices signal the valve status to control panels, allowing operators to monitor multiple valves safely without being near potentially hazardous gas lines.

Finally, a careful operational check can confirm the valve’s status. Slowly opening or closing the valve while monitoring gas flow, pressure, or appliance response allows a safe verification, provided all safety precautions are followed, including ensuring no ignition sources are nearby and the area is well-ventilated.

In summary, determining if a gas valve is open or closed relies on visual cues, pressure measurements, electronic indicators, or controlled operational checks, all conducted with safety as the highest priority.

What is a safety shut off valve for gas?

A safety shut-off valve for gas is a critical device designed to automatically or manually stop the flow of gas in a pipeline or appliance when unsafe conditions occur. Its primary purpose is to prevent accidents such as leaks, explosions, or fires, protecting both people and equipment in residential, commercial, and industrial settings.

There are several types of gas safety shut-off valves. Manual shut-off valves are operated by a handle or lever, allowing users to quickly stop gas flow during maintenance, emergencies, or system inspections. These are common in home appliances, gas meters, and industrial pipelines. Automatic shut-off valves respond to abnormal conditions without human intervention. They may be triggered by excessive pressure, temperature changes, flame failure, or gas detection sensors. For example, a valve connected to a gas detector can close automatically if a leak is detected, preventing dangerous accumulation of flammable gas.

Safety shut-off valves are often integrated into gas regulators, furnaces, boilers, or appliances. In industrial systems, they may form part of a larger safety system, such as an emergency shutdown circuit. Key features include fast response, reliability under high pressure, and compatibility with the specific type of gas used, whether natural gas, propane, or industrial gases.

Maintenance and regular testing of safety shut-off valves are essential. Valves must remain free of dirt, corrosion, and mechanical wear to function correctly. Most standards, such as NFPA or ASME codes, require periodic inspection, testing, and documentation to ensure that valves operate reliably when needed.

In summary, a gas safety shut-off valve is a vital protective device that stops gas flow during unsafe conditions, helping prevent leaks, fires, and explosions. Its proper selection, installation, and maintenance are essential for safe gas system operation.

Ssdj zl -* f c lq gas safety shut off valve spec

The SSDJ ZL-*/F C LQ series gas safety shut-off valve is a specialized device designed to provide reliable overpressure and emergency shut-off protection in gas systems. These valves are commonly used in natural gas, LPG, and industrial gas applications, where rapid and secure interruption of gas flow is critical to prevent accidents, leaks, or explosions.

The valve typically features a robust body construction, often made of corrosion-resistant materials such as brass, stainless steel, or high-strength alloys, ensuring durability in harsh environments. It incorporates either manual or automatic actuation. Manual versions allow operators to close the valve quickly during maintenance or emergencies, while automatic models respond to abnormal conditions like excessive pressure, flame failure, or gas leakage, shutting off the flow without human intervention.

Key specifications of the SSDJ ZL-*/F C LQ series include pressure ratings, flow capacity, and temperature range. These valves are generally designed to handle medium to high-pressure systems, with precise pressure setpoints calibrated according to the gas type. The flow coefficient (Cv) is engineered to ensure minimal pressure drop while maintaining reliable shut-off performance. Some models include a solenoid or electric actuator, enabling integration with remote monitoring and control systems for industrial automation.

The valve’s design emphasizes safety, reliability, and ease of maintenance. Features such as replaceable internal seals, clear visual indicators for open or closed status, and standardized mounting dimensions facilitate installation and service. Compliance with international standards, such as ISO, NFPA, or local gas safety codes, ensures that the valve meets stringent safety requirements.

In summary, the SSDJ ZL-*/F C LQ gas safety shut-off valve is a high-performance protective device, combining robust construction, precise pressure control, and automated or manual shut-off capabilities to ensure safe and reliable gas system operation in residential, commercial, or industrial applications.