高压燃气减压阀未进气状态：

        一级膜片在一级弹簧预应力的作用下，使一级杠杆组中的杠杆与进气阀芯的钢球保特一定的间隙，阀口处于常开状态。
        二级膜片在二级弹簧的作用下，将二级杠杆一端下移，使二级阀口处于常开状况。
        三级杠杆在弹簧张力作用下，使三级杠杆与阀座处于常闭。

高压燃气减压阀进气及工作状态：

        当25Mpa天然气通过进气阀芯组进入一级减压腔使一级膜片逐步上移，当一级减压腔气压达到一定值，膜片的推力完全克服一级弹簧的预紧力时，作用于杠杆的合力矩使阀芯关闭阀口。燃气流量随发动机负荷变化而变化，在弹簧与膜片相互作用下，阀口随时变化开度，输出压力稳定在0.4～0.6Mpa，完成一级减压。
        经过一级减压的气体进入二级减压腔，随发动机负荷的变化，二级膜片通过二级传动杆带动二级杠杆的阀片（阀门）调节二级阀口的开度。随着三级减压腔流量的变化不断改变二级阀口的开度，保特输出压力在0.08Mpa左右。
        在只进气状态下，二级减压腔的气体克服三级调节弹簧的张力，打开三级阀座进入三级减压腔，使三级减压腔的压力稳定在0.3～0.5KPa。当发动机起动时，有0.5Kpa的低压天然气进入发动机，便于起动。发动机运转产生真空吸力将三级膜片吸向下方，三级膜片组推动三级杠杆，打开三级阀座，二级减压腔的气体进入三级减压腔，混合气由低压出气口经低压管动力阀进入发动机。三级阀口的开度随发机负荷吸气负压的变化而变化，以满足发动机的各种工况所需要的燃气流量。

高压燃气减压阀

高压燃气减压阀是一种专门设计用于燃气输配系统的关键控制设备。其主要功能是将来自主管道或储气设备的高压燃气，稳定地降低至下游管网或设备所需的较低且安全的压力水平。该阀门对于保障燃气供应系统的安全、稳定运行至关重要。

高压燃气减压阀核心工作原理：

阀门通过感应其出口端的压力，利用内部机构（如膜片、活塞和弹簧）的反馈作用，自动调节阀瓣的开度。当出口压力因流量减小或上游压力升高而增大时，阀门关小以限制流量；反之则开大。这种连续、自动的调节确保了出口压力的恒定。

高压燃气减压阀主要特点与要求：

1. 高安全性： 采用防爆设计、紧密的关断密封，确保在故障或关闭时无燃气泄漏。通常配备安全切断阀或超压放散阀作为安全冗余。

2. 准确稳压： 即使在进口压力大幅波动或下游流量急剧变化的情况下，也能维持出口压力的高度稳定。

3. 材料与密封兼容性： 阀体、内件及密封材料必须与燃气介质（如天然气、液化石油气等）兼容，耐腐蚀，并适应燃气中可能含有的杂质。

4. 高稳定性： 设计用于不间断长期运行，故障率低，维护周期长。

5. 宽泛的压力适用范围： 能够处理极高的进口压力（可从几兆帕至十几兆帕不等），并将其降至所需的低压或中压。

高压燃气减压阀典型应用：

· 城市门站（从高压长输管线向城市中压管网调压）

· 工业用户专线调压站

· CNG（压缩天然气）加气站及减压站

· LNG（液化天然气）气化站调压系统

· 区域调压箱/柜

High-Pressure Gas Pressure Reducing Valve Product Overview

A High-Pressure Gas Pressure Reducing Valve (PRV) is a critical control device specifically engineered for gas distribution systems. Its primary function is to reliably  precisely reduce high-pressure gas  main pipelines  storage facilities to a lower, safe pressure level required by downstream networks  equipment. This valve is essential for ensuring the safety, stability,  efficiency of the gas supply system.

Core Working Principle:

The valve automatically adjusts the opening of the disc via the feedback mechanism of its internal components(such as a diaphragm, piston,  spring) by sensing the pressure at its outlet. If the outlet pressure increases due to reduced flow  raised upstream pressure, the valve closes to restrict flow,  vice versa. This continuous, automatic regulation maintains a constant outlet pressure.

Key Features  Requirements:

1. High Safety: Features explosion-proof design  tight shut-off sealing to ensure zero gas leakage during failure  closure. Often equipped with safety shut-off valves  overpressure relief valves as safety redundancy.

2. Precise Pressure Stabilization: Maintains highly stable outlet pressure even under significant inlet pressure fluctuations  drastic downstream flow changes.

3. Material  Seal Compatibility: Body, trim,  sealing materials must be compatible with the gas medium (e.g., Natural Gas, LPG), corrosion-resistant,  tolerant of potential impurities in the gas.

4. High Reliability: Designed for long-term, uninterrupted operation with low failure rates  extended maintenance intervals.

5. Wide Pressure Operating Range: Capable of handling very high inlet pressures (which can range  several MPa to tens of MPa)  reducing them to the required low  medium pressure.

Typical Applications:

· City Gate Stations (Pressure regulation  high-pressure transmission pipelines to medium-pressure city networks)

· Pressure Regulating Stations for Industrial Customers

· CNG (Compressed Natural Gas) Filling Stations  Decompression Stations

· Pressure Regulation Systems in LNG (Liquefied Natural Gas) Vaporization Stations

· District Regulator Boxes/Cabinets