مقدمة المقارنة: صمام بوابة إسفين وصمام بوابة موازية

صمام البوابة هو صمام يتحرك فيه القرص في الاتجاه الرأسي على طول الخط المركزي للمسار. تستخدم صمامات البوابة بشكل أساسي لقطع خطوط الأنابيب.

يمكن تقسيم أحد التصنيفات الأكثر شيوعًا إلى صمامات البوابة الإسفينية وصمامات البوابة المتوازية وفقًا لتكوين سطح الختم.

يمكن تقسيم صمام البوابة الإسفينية إلى: نوع قرص واحد, نوع القرص المزدوج ونوع القرص المرن; يمكن تقسيم صمام البوابة المتوازية إلى نوع قرص واحد ونوع قرص مزدوج.

سطح الختم لصمام البوابة المتوازية يكون عموديًا على محور الأنبوب, إنه, سطحي الختم متوازيان مع كل صمام بوابة استيراد آخر.

يكون سطح الختم لصمام البوابة الإسفينية بزاوية مع محور الأنبوب, إنه, سطحي الختم في صمام بوابة على شكل إسفين. يعتمد حجم زاوية ميل الإسفين بشكل أساسي على درجة حرارة الوسط, عموما ارتفاع درجة حرارة العمل, كلما كانت الزاوية الملتقطة أكبر, من أجل تقليل احتمالية إسفين البوابة عند تغير درجة الحرارة.

The design concepts, operating principles, performance characteristics, and suitable applications for these two structures differ significantly. For end-users, a thorough understanding of these differences is key to making informed selection decisions, ensuring system stability, and optimizing procurement costs.

As a globally recognized top-tier valve manufacturer, Farpro YD Valve possesses extensive valve data and information to enlighten our customers on gate valve knowledge. Here, the Farpro YD Team will provide a detailed explanation of the distinctions between parallel gate valves and wedge gate valves, offering valuable insights based on our vast experience. سوف يشرح Farpro بالتفصيل الفرق بين صمامات البوابة المتوازية والإسفينية:

Part One: Gate Valve Fundamentals Recap

Before diving into the comparison, let’s briefly review the basic concepts of gate valves:

1. Operating Principle: By rotating a handwheel or activating an actuator, the valve stem is driven to perform a lifting motion (Outside Screw & نير – نظام التشغيل&Y type) or remain in place while the gate moves (الجذعية غير الصاعدة – NRS type). This action drives the connected gate up or down within the valve body, perpendicular to the fluid channel. When the gate is fully lifted, the passage is completely open, offering minimal resistance to flow. When the gate is fully lowered and seals tightly against the valve seat, the passage is completely closed, achieving shut-off.

2. Main Advantages:

   • Low Flow Resistance: When fully open, the gate is completely withdrawn from the flow path, allowing the medium to flow almost straight through, resulting in very low pressure drop.

   • Relatively Low Operating Torque: Compared to globe valves, the gate moves perpendicular to the flow direction, requiring less force to overcome fluid pressure during opening and closing.

   • No Restriction on Flow Direction: Gate valves are typically bidirectional, meaning they can be installed and operated regardless of the flow direction.

   • Wide Range of Applications: Suitable for various media (liquids, غازات, بخار, slurries, إلخ.), الضغوط, and temperature ranges.

   • Relatively Simple Structure, سهولة الصيانة.

3. Main Disadvantages:

   • Not Suitable for Throttling: In a partially open state, high-velocity fluid can easily erode the sealing surfaces, leading to valve damage and leakage. بالإضافة إلى, the relationship between flow rate and opening percentage is non-linear, making precise flow control difficult.

   • Slow Operation: The gate has a relatively long travel distance, requiring significant time to complete a full open or close cycle.

   • Large Overall Dimensions and Height: Especially for OS&Y types, the rising stem requires considerable overhead space when the valve is open.

   • Sealing Surfaces Prone to Abrasion: During opening and closing, relative friction occurs between the gate and seat sealing surfaces, particularly under pressure or when the medium contains solid particles.

مميزات صمامات البوابة المتوازية

صمام البوابة الموازية هو نوع القرص المزدوج الأكثر شيوعًا, من أجل إغلاق جسم الصمام والبوابة بين سطحي الختم الملامسين بإحكام, غالبا ما تستخدم في ساندويتش لوحة البوابة مع إسفين التوجه على الوجهين.

في هذا الطريق, عند إغلاق الصمام, يتم الضغط تدريجيًا على ملامسة إسفين الدفع على الوجهين مع الجزء السفلي من جسم الصمام, دفع لوحة البوابة المزدوجة لفتحها بحيث يكون سطح إغلاق البوابة وجسم الصمام محكم الغلق. عادةً ما يتم تطبيق هذا النوع من البوابة المتوازية ذات القرص المزدوج في ظروف العمل التي لا تحتاج إلى الفتح والإغلاق بشكل متكرر, وإبقاء البوابة مفتوحة بالكامل أو مغلقة بالكامل.

Main Structural Types:

Parallel Slab Gate Valve / Through-Conduit Gate Valve:

• • • Structure: Typically features a single, flat gate (slab) with a bore (port) machined through it, matching the pipeline diameter. The slab slides between two parallel seats.

    • Operation: To close, the slab slides down, and its solid portion blocks the flow path. To open, the slab slides up, aligning the through-conduit port with the pipeline, creating a smooth, unobstructed passage. Sealing usually relies on line pressure pushing the slab against the downstream seat (self-sealing), sometimes assisted by spring-loaded seats providing initial sealing force.

    • Advantages:

      • الحد الأدنى من مقاومة التدفق: When fully open, the port matches the pipe bore, offering a smooth, non-restrictive flow path, ideal for pipelines requiring low pressure drop, such as long-distance transport lines.

      • Sealing Surface Protection: In both fully open and fully closed positions, the sealing surfaces are shielded from the main flow, protecting them from erosion and wear, especially suitable for media containing solid particles or abrasives.

      • Suitable for Pigging: The smooth through-conduit allows pipeline inspection gauges (Pigs) to pass through.

      • Relatively Lower Operating Torque: Primarily needs to overcome friction, no wedging force involved.

    • Disadvantages:

      • Sealing tightness at low pressure might be less positive than wedge types, as self-sealing effectiveness depends on sufficient differential pressure.

      • Structural dimensions, particularly face-to-face length, can be larger.

      • Manufacturing costs can be higher, especially for large diameters and high pressure ratings.

صمام بوابة القرص المزدوج المتوازي:

• • • Structure: Comprises two parallel discs, usually with a spring or spreader mechanism (like a wedge or toggle) located between them.

    • Operation: As the gates descend near the closed position, the spring or spreader mechanism activates, forcing the two discs outwards against their respective upstream and downstream seats, achieving a double seal. During opening, this spreading force is released first, allowing the discs to lift freely.

    • Advantages:

      • Excellent Bidirectional Sealing: Provides effective sealing regardless of the direction of flow or pressure.

      • Reliable Low-Pressure Sealing: The mechanical spreading force ensures a tight seal even at very low differential pressures.

      • Avoids Thermal Binding: The absence of a wedge angle eliminates the risk of jamming due to temperature changes or pressure fluctuations, making it ideal for high-temperature, high-differential pressure, and thermal cycling applications.

      • Potential for Self-Relieving Function: Some designs allow overpressure trapped in the body cavity to automatically bleed off to the upstream side, enhancing safety (specific design must be confirmed).

    • Disadvantages:

      • Relatively complex structure with more parts, leading to higher manufacturing and maintenance costs.

      • Potential for debris accumulation between the discs, which could affect sealing or operation.

      • Typically larger and heavier than wedge gate valves of the same specification.

Parallel Gate Valve Characteristics Summary:

Advantages:

• No risk of thermal binding, suitable for high-temperature and fluctuating temperature service.

• Relatively lower operating torque (especially slab gate type).

• Through-conduit design protects sealing surfaces, suitable for particulate media and pigging operations.

• Double disc design offers reliable bidirectional and low-pressure sealing.

Disadvantages:

• Single-gate self-sealing types may have weaker sealing at very low pressures.

• Double disc types are structurally complex, costly, and bulky.

• High manufacturing precision required, especially for parallelism and flatness.

Typical Application Areas:

• Oil and gas long-distance pipelines (primarily through-conduit parallel slab gate valves, often to API 6D).

• High-temperature steam lines (e.g., main steam lines in power plants, often using double disc parallel types).

• Refineries and chemical plants for high-temperature, high-pressure services or where pigging is required.

• Low-pressure gas distribution lines.

• Applications requiring reliable bidirectional sealing.

عادة, في حالة الاتصال المباشر مع خط الأنابيب, فمن المستحسن استخدام صمام البوابة المتوازية, والتي لديها مزايا الهيكل المدمج, وزن خفيف, حجم صغير, صيانة سهلة, عملية مريحة ومرنة, إلخ.

مميزات صمامات البوابة الإسفينية

صمام بوابة إسفين لديها صمام بوابة إسفين قرص واحد / مزدوج. مزايا صمام البوابة الإسفينية ذات القرص المزدوج هي الختم بينما تكون زاوية متطلبات الدقة منخفضة, التغيرات في درجات الحرارة ليست سهلة لجعل إسفين البوابة, يمكن تعويض تآكل سطح الختم بإضافة حشوات.

العيب هو أن الهيكل معقد, من السهل الالتصاق في الوسط الجاف, والأهم من ذلك أنه من السهل أن تسقط اللوحة الحاجزة العلوية والسفلية بعد سنوات من التآكل.

لذلك, يتم استخدام صمام البوابة الإسفينية ذات القرص الواحد بأعداد كبيرة نظرًا لبنيتها البسيطة واستخدامها الموثوق, خاصة بعد التغيير إلى بوابة مرنة, والتي يمكن أن تنتج تشوهًا مرنًا طفيفًا للتعويض عن الانحراف الناتج في معالجة زاوية سطح الختم.

Wedge Angle: The selection of the wedge angle is a critical design parameter, typically dependent on the medium temperature, تصنيف الضغط, and valve size.

• Temperature Influence: Higher operating temperatures lead to more significant thermal expansion differences in materials. To prevent the gate from becoming “wedged shut” or experiencing “thermal binding” at high temperatures, a larger wedge angle is usually chosen. على العكس من ذلك, for ambient or low temperatures, a smaller wedge angle can be used for better sealing and lower operating torque.

• Common Angles: Generally range from 3° to 10°. على سبيل المثال, واجهة برمجة التطبيقات 600 often specifies 5° or higher.

Main Structural Types：

• Solid Wedge Gate Valve:

  • Structure: The gate is a single, solid wedge piece.

  • Advantages: Simplest structure, robust, متين, relatively low cost, less prone to trapping debris, suitable for most general applications, especially in small to medium sizes and low to medium pressures.

  • Disadvantages: Poor adaptability to sealing surface machining inaccuracies and valve body deformation. Temperature changes or pipeline stresses can lead to poor sealing or gate jamming (thermal binding). Closing under high differential pressure can create excessive wedging force, making opening difficult.

• Flexible Wedge Gate Valve:

  • Structure: The main body of the gate is still wedge-shaped, but features cuts, slots, or a specific peripheral design allowing it some elastic deformation capability.

  • Advantages: Can compensate for minor valve body distortions caused by temperature changes or pipeline loads, enhancing sealing reliability. Effectively prevents high-temperature thermal binding. Less demanding on the precision of sealing surface angle machining. Offers better sealing performance than solid wedges. Farpro YD Valve has mature technology in the design and manufacture of high-performance flexible wedge gate valves.

  • Disadvantages: Structure is slightly more complex than a solid wedge, leading to a marginally higher manufacturing cost. Not ideal for media containing significant solid particles or prone to scaling, which could clog the flexible structure.

• Split Wedge / Double Disc Wedge Gate Valve:

  • Structure: Consists of two independent discs (often connected by a mechanism like a ball-and-socket joint, pin, or dovetail) forming a composite wedge shape. Upon closing, external forces (like stem thrust or a bottom spreader) allow the two discs to move slightly apart laterally, pressing independently against their respective seats.

  • Advantages: Both sealing surfaces can achieve independent contact with the seats, providing excellent self-alignment. This offers better adaptability to seat angle variations and body deformation, resulting in superior sealing performance, especially under high pressure and high temperature conditions. Minor sealing surface wear can be compensated for by the outward movement of the discs. Less prone to thermal binding.

  • Disadvantages: Most complex structure, more parts, higher manufacturing cost, relatively more difficult to assemble and repair. Potential for media to become trapped between the discs. In designs with bottom guides, corrosion and detachment of these guides over time can impair function.

Wedge Gate Valve Characteristics Summary:

• Advantages:

  • أداء الختم ممتاز: Relies on wedging action for positive sealing, providing high sealing pressure and reliability.

  • Relatively compact structure (compared to parallel gate valves of the same size).

  • Wide range of applications: Suitable for various pressures, درجات الحرارة, and media (selection depends on materials and specific structure).

  • Mature technology, highly standardized (e.g., واجهة برمجة التطبيقات, ASME standards).

• Disadvantages:

  • Risk of thermal binding: Especially with solid wedges in applications with significant temperature fluctuations or cooling after high-pressure closure.

  • Relatively high operating torque: Must overcome the friction associated with the wedging action.

  • Sealing surfaces prone to wear: Due to relative sliding friction during operation.

  • Not suitable for rapid opening/closing.

Typical Application Areas:

• Power industry (خطوط البخار, feedwater systems, ash handling systems, إلخ.)

• النفط والغاز (oilfields, المصافي, some pipeline applications)

• الصناعة الكيميائية (various process fluid lines)

• Metallurgy and mining (process water, slurry handling, إلخ.)

• Municipal water supply and wastewater treatment

• General industrial services

على العموم, يتم تخفيف جذع صمام البوابة الإسفينية ونيترة السطح للحصول على مقاومة جيدة للتآكل ومضادة للجرجر. يتم تصنيع البوابة وختم المقعد من لحام تراكب السبائك الصلبة, وهو مقاوم للاهتراء, مقاومة درجات الحرارة العالية, مقاومة للتآكل, أداء جيد ضد الجرجر وعمر خدمة طويل. اكتمل تنوع مواد جسم الصمام, التعبئة, الحشية وفقًا لظروف العمل الفعلية أو متطلبات المستخدم المعقولة الاختيارية, يمكن تطبيقها على مجموعة متنوعة من الضغط, درجة الحرارة وظروف عمل الوسائط.

Wedge Gate Valve vs. Parallel Gate Valve – In-Depth Comparison

To aid in making a clearer choice, we directly compare these two valve types across several key dimensions:

Selection and Purchasing Guidance – Professional Advice from Farpro YD Valve

Choosing between a wedge gate valve and a parallel gate valve isn’t about determining which one is universally “better,” but rather identifying which one is “more suitable” for a specific application. As a responsible valve supplier, Farpro YD Valve recommends considering the following key factors during selection:

Operating Conditions are Fundamental:

• Media Properties: Is it a clean fluid, غاز, بخار, or does it contain solid particles, الطين, viscous material, or crystallizing substances? This directly impacts whether sealing surface protection is needed (advantage: parallel slab gate) or if specific materials and structures are required.
• تصنيف الضغط: In high-pressure applications, the positive sealing of a wedge gate valve (especially split wedge) can be very reliable, but consider the operating torque and potential binding issues under high differential pressure. Parallel double disc types also perform well under high pressure.
• Temperature Range & Fluctuation: For high temperatures or significant temperature swings, parallel gate valves (lacking a wedge angle) are the preferred choice to avoid thermal binding. If selecting a wedge type, prioritize flexible wedge or split wedge designs and pay attention to the wedge angle selection.

Functional Requirements Guide the Choice:

• Sealing Level Requirement: Is zero leakage or a very high sealing class required? Split wedge and parallel double disc types generally offer superior sealing performance.
• Operating Frequency: Gate valves are inherently unsuitable for frequent operation. If relatively frequent cycling is necessary, consider a parallel gate valve with lower operating torque or select an appropriate actuation method.
• Need for Pipeline Pigging: For applications like long-distance pipelines where pig passage is required, a through-conduit parallel gate valve is mandatory.
• Need for Automatic Cavity Pressure Relief: Certain parallel double disc gate valves offer this safety feature; confirm based on specific process requirements.

Economic and Maintenance Considerations:

• • Initial Purchase Cost: عمومًا, solid/flexible wedge gate valves have the lowest cost, followed by slab gate and split wedge types, with double disc parallel gate valves typically being the most expensive. لكن, this is a general guideline influenced by materials, standards, brand, إلخ.

  • Maintenance Convenience and Cost: Simpler structures usually mean easier maintenance. Consider the valve’s expected lifespan, maintenance intervals, and replacement costs.

  • Space and Weight Constraints: Parallel gate valves are often larger and heavier, requiring consideration of installation space and support structures.

Industry Codes and Standards:

• • Ensure the selected valve complies with relevant industry codes (e.g., زيت & غاز, قوة, المواد الكيميائية) and standards (e.g., واجهة برمجة التطبيقات, ASME, في, غيغابايت). All Farpro YD Valve products are designed and manufactured in strict accordance with international and national standards.

Purchasing Recommendations

• Define Needs Clearly, Communicate Thoroughly: Before inquiring or purchasing, provide your supplier (like Farpro YD Valve) with detailed operating parameters and functional requirements. Our technical team will leverage your specific needs to recommend the most suitable valve type and specification.

• Focus on Quality and Brand Reputation: Valves are critical equipment; choosing a reliable brand with a proven quality record is essential. Farpro YD Valve operates under robust quality management systems (e.g., ايزو 9001) and utilizes advanced manufacturing and testing equipment to ensure every valve meets high-quality standards.

• Consider Total Cost of Ownership (TCO) / Lifecycle Cost: Look beyond the initial purchase price. Evaluate the valve’s performance, مصداقية, خدمة الحياة, maintenance costs, and the potential costs associated with failure. Choosing a high-performance, long-lasting valve (even if initially more expensive) often yields better long-term economic benefits.

• Value Technical Support and Service: Select a supplier capable of providing professional technical consultation, selection guidance, after-sales service, and spare parts availability. Farpro YD Valve is committed to offering a seamless and supportive experience for our customers.

خاتمة

Wedge gate valves and parallel gate valves, as two major branches of the gate valve family, each possess unique design philosophies, performance advantages, and application niches.

• صمامات بوابة إسفين, with their powerful wedging seal, relatively compact structure, and broad applicability, dominate many conventional industrial sectors. Derived designs like the flexible wedge and split wedge further enhance performance and reliability.

• Parallel gate valves, characterized by their immunity to thermal binding, suitability for high temperatures and particulate media (through-conduit type), and excellent bidirectional and low-pressure sealing capabilities (double disc type), demonstrate irreplaceable advantages in specific high-end applications and demanding operating conditions, such as long-distance pipelines and high-temperature steam systems.

There is no absolute superiority, only relative suitability. Understanding their core differences and making scientific selections based on specific application requirements are prerequisites for ensuring the safe, فعال, and economical operation of fluid control systems.

Farpro YD Valve offers a comprehensive product line of both wedge and parallel gate valves, covering various materials, تقييمات الضغط, actuation methods, and standard compliance. We not only provide standardized high-quality products but also offer customized solutions tailored to your unique needs. Whatever fluid control challenges you face, our professional team is ready to provide the most accurate selection advice and the highest quality valve products.

Choose Farpro YD Valve – Choose Professionalism, Choose Reliability. We welcome you to contact us anytime to discuss your valve requirements!