Wafer Check Valves

In large-diameter pipelines, wafer check valves (typically dual-disc) feature a more constricted flow path compared to swing check valves. The split disc structure and internal spring components create significant flow obstructions, leading to higher pressure loss under large flow rates. For fire protection or industrial water supply systems with large-diameter lines, this excess pressure drop can reduce the actual delivery flow rate, failing to meet the system's peak demand. Unlike swing check valves with unobstructed full-bore flow, wafer models struggle to balance low resistance and backflow prevention in large-caliber applications.

Large-diameter wafer check valves face severe structural stress from high-velocity fluid impact. Their dual-disc design relies on springs to control opening and closing, and in large-caliber pipelines, the increased fluid momentum causes frequent valve disc fluttering and vibration. Over time, this continuous oscillation accelerates spring fatigue and disc deformation, compromising the valve's structural integrity. Swing check valves, with their rigid hinge-mounted single disc, maintain stable movement even at high flow velocities in large-diameter lines, avoiding such fatigue-related failures.

Sealing reliability is a critical limitation for wafer check valves in large-diameter applications. The larger sealing surface area of big-size dual discs leads to uneven pressure distribution when the valve closes. Minor misalignment caused by fluid impact or component wear can create micro-gaps, resulting in persistent leakage. In contrast, swing check valves use a single, uniformly stressed sealing surface that forms a tighter seal in large-diameter pipelines. Wafer valves also require more precise machining for large seals, and wear accelerates faster under high pressure, reducing long-term sealing performance.

Maintaining large-diameter wafer check valves is far more complex than servicing swing check valves. The dual-disc, spring, and sealing components of large-caliber wafer models are heavier and more compactly assembled, requiring full disassembly of the pipeline flanges to access internal parts. This often demands specialized lifting tools and longer downtime. Swing check valves allow partial in-line maintenance, as their single disc can be accessed from one side without full flange removal. For large-diameter industrial pipelines, this complexity increases operational costs and system downtime significantly.