Coliter ® Single Port Flange Exhaust Valve – PN0.6~2.5, ≤80°C, Automatic Air Release for Water Pipelines
QB1 Single Port Flange Exhaust Valve – Ductile Iron Body with Stainless Steel Float for Automatic Trapped Air Venting in Main Water Lines
The Coliter® QB1 Single Port Flange Exhaust Valve is an automatic air release valve designed to efficiently remove trapped air from water pipelines during system filling or operation, preventing airlocks, noise, corrosion, and reduced pump efficiency. Installed at high points in the pipeline—such as pump inlets, manifolds, or elevated sections—it ensures smooth flow and protects against pipe deformation or rupture caused by air accumulation. The valve features a robust ductile iron (QT450) body, a precision-machined stainless steel floating ball as the internal sealing mechanism, and a single vertical exhaust port. Under normal conditions, the float rises with water level, sealing the orifice; when air accumulates, the float drops, allowing air to vent automatically. Rated for nominal pressures from PN0.6 to PN2.5 (0.6–2.5 MPa), it operates reliably within a temperature range of -10℃ to 80℃ and is suitable exclusively for water as the medium. Compliant with Chinese National Standards, available in sizes DN20, DN25, DN40, and DN50, with flanged end connections per standard specifications. The QB1 is an essential, maintenance-free component for municipal water supply, HVAC systems, irrigation networks, and industrial water circuits—ensuring optimal hydraulic performance and system longevity.
Installation diagram
Product Description
| DN | D | D1 | Φ | H |
|---|---|---|---|---|
| 20 | 105 | 75 | 135 | 205 |
| 25 | 115 | 85 | 135 | 205 |
| 40 | 145 | 115 | 150 | 205 |
| 50 | 160 | 125 | 150 | 205 |
The QB1 single port exhaust valve is a circular body with a stainless steel floating ball as its internal structure. This valve is divided into two types: threaded and flanged.
QB1 type is suitable for pipelines with a working temperature of ≤ 80 ℃, as a device for removing gas from the pipeline.
The QB2 exhaust valve mainly consists of a valve body, a valve disc, a valve cover, a valve stem, a floating ball, etc. This valve is suitable for pipelines with water as the medium, and serves as a device for removing gas from the pipeline to improve the efficiency of water transmission equipment and protect the pipeline from deformation and rupture. It is an essential equipment for pipelines.
Main Performance Specification
| Nominal Diameter | 20–50mm |
| Nominal pressure | 0.6–2.5MPa |
| Applicable temperature | -10～80°C |
| Standard | National Standard |
| Material quality | Nodular cast iron |
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Faq - Frequent questions
Introduction to Exhaust valve
Coliter®’s exhaust valves automatically vent trapped air from heating, cooling, and water supply pipelines to prevent airlocks, noise, corrosion, and reduced efficiency. The series includes the QB1 single-port flange exhaust valve for main lines, KB1 single-port quick exhaust valve with enhanced discharge speed, and the CARX1.0 compound automatic air release valve that handles both large initial air volumes and micro-bubbles during operation. Constructed from high-quality cast iron or brass with stainless steel float mechanisms, these valves operate at PN16 (1.6 MPa) and temperatures up to 110°C. Ideal for installation at system high points, pump inlets, and manifold tops—ensuring smooth flow, pump protection, and optimal thermal performance in HVAC and plumbing networks.
