Z44H双平行浮动闸阀代替了楔式闸板，通过主副闸板架的相对运动，水平推动浮动闸板与阀座接触。开启瞬间利用弹簧的涨力推动主副阀瓣相对移动，同时使主副闸板快速脱离阀座面，减小摩擦。由于其优良的密封特性，可广泛应用于石油、化工等行业高温高压管路系统。

Z44H双平行浮动闸阀

型号“Z44H”遵循中国阀门型号编制标准（JB/T 308），其含义如下：

· Z： 代表闸阀（Zha Fa）。

· 4： 代表连接形式为法兰连接（Fa Lan）。

· 4： 代表结构形式为双闸板（Shuang Zha Ban）。

· H： 代表密封面材料为合金钢（He Jin Gang），通常指阀座密封面采用不锈钢或硬质合金等。

因此，Z44H 明确表示一种法兰连接的双闸板、合金钢密封的闸阀。其核心特征在于“双平行浮动闸板”结构。

Z44H双平行浮动闸阀是一种采用平行式双闸板结构的闸阀。其闸板由两块平行的闸板组成，中间设有弹性元件（如弹簧或顶楔）。关闭时，介质压力推动两块闸板分别向两侧的阀座移动，形成密封。这种“浮动”机制使其具有良好的密封补偿能力，尤其适用于中低压、温度波动较大或对密封性要求较高的工况，能有效避免因温度变化引起的闸板卡阻问题。

Z44H双平行浮动闸阀主要特点

1. Z44H双平行浮动闸阀自动补偿密封： 当阀门关闭时，介质压力作用于两块闸板之间，迫使它们向外侧浮动，紧密地压紧在两个阀座上，实现双向密封。这种自紧式密封效果随着介质压力的升高而增强。

2. Z44H双平行浮动闸阀出众的密封性能： 双闸板设计使得密封面之间的接触更加均匀和柔和，减少了密封面的磨损，即使在压力不高的情况下也能实现良好的密封。

3. Z44H双平行浮动闸阀防卡阻设计： 与楔式闸阀相比，平行式闸板不易因温度变化而产生的热胀冷缩而卡死在阀座中，操作力矩相对稳定，启闭轻便。

4. Z44H双平行浮动闸阀流阻小： 全开时，介质通道直通，流阻小，压力损失低。

5. Z44H双平行浮动闸阀维护方便： 当密封面磨损后，中间的弹性元件能提供一定的补偿，延长使用寿命。必要时，可更换闸板组件。

适用工况与领域

· 介质： 水、蒸汽、油品、天然气等。

· 工况： 中低压（常用压力等级为PN16-PN40，Class 150-Class 300），温度波动较大的场合。

· Z44H双平行浮动闸阀应用领域：

  · 城市燃气输送管网。

  · Z44H双平行浮动闸阀供热系统。

  · 石油、化工行业的常压、低压装置。

  · 通用工业管道系统。

Product Overview of Z44H Double Disc Parallel Seat Gate Valve

I. Model Designation Interpretation

The model"Z44H" complies with the Chinese valve model designation standard (JB/T 308), with the following meaning:

· Z: Stands for Gate Valve.

· 4: Indicates the connection type as Flange.

· 4: Denotes the structure type as Double Disc.

· H: Signifies the sealing surface material is Alloy Steel (typically meaning stainless steel  hard alloy for the seat).

Therefore, Z44H explicitly refers to a flanged, double-disc, alloy-steel sealed gate valve. Its core feature is the "double disc parallel seat" design.

Product Introduction

The Z44H Double Disc Parallel Seat Gate Valve employs a parallel dual-disc structure.The gate consists of two parallel discs with a spreading mechanism (like a spring  a wedge) between them. When closing, the medium pressure acts between the two discs, forcing them to float outward against their respective seats to form a seal. This "floating" mechanism provides excellent sealing compensation, making it particularly suitable for medium-to-low pressure applications, services with significant temperature fluctuations,  situations demanding high sealing integrity. It effectively prevents gate jamming due to thermal expansion  contraction.

Main Features

1. Self-Compensating Sealing: Upon closure, medium pressure acts between the two discs, forcing them to float apart  press tightly against the two seats, achieving bidirectional sealing. This self-energizing sealing effect improves with increasing medium pressure.

2. Excellent Sealing Performance: The double-disc design ensures more uniform  gentle contact between the sealing surfaces, reducing wear. It provides effective sealing even at lower pressures.

3. Anti-Jamming Design: Compared to wedge-type gate valves, the parallel discs are less prone to jamming in the seats due to thermal expansion  contraction caused by temperature changes. The operating torque is relatively stable, allowing for easy opening  closing.

4. Low Flow Resistance: When fully open, it provides a straight-through flow path with minimal resistance  pressure drop.

5. Ease of Maintenance: The central spreading mechanism compensates for seal wear, extending service life. The disc assembly can be replaced when necessary.

. Suitable Services  Applications

· Media: Water, steam, oil, natural gas, etc.

· Service Conditions: Medium to low pressure (common pressure classes: PN16-PN40, Class 150-Class 300), applications with significant temperature variations.

· Application Fields:

  · Urban gas distribution networks.

  · District heating systems.

  · Atmospheric  low-pressure units in the petroleum  chemical industries.

  · General industrial piping systems.

核心术语中英对照：

· Z44H双平行浮动闸阀：Z44H Double Disc Parallel Seat Gate Valve

· 双闸板：Double Disc / Twin Disc

· 平行式闸板：Parallel Disc

· 浮动机制：Floating Mechanism

· 弹性元件：Spreading Mechanism / Spring

· 双向密封：Bidirectional Sealing

· 自紧式密封：Self-Energizing Seal

· 防卡阻：Anti-Jamming

· 密封补偿：Sealing Compensation