Water distributors and collectors must match total flow, branch flow, pressure class and service layout; a poorly sized manifold can create branch imbalance, excess pressure loss or inaccessible piping.
YONGFAN manufactures custom supply distributors and return collectors (DN50 to DN500 main headers, DN15 to DN300 nozzles) in Q235-B, Q345R, SS304, and SS316L, engineered for ≤1.0 m/s internal header velocity.
High fluid velocity creates a steep pressure gradient along the header, making flow balancing between near and far branches virtually impossible.
The manifold minimizes header pressure drop, but each branch still requires its own balancing valve or control valve for independent circuit flow regulation.
A distribution header is not automatically a hydraulic decoupler. Primary-secondary decoupling requires dedicated volume and baffle geometry.
Branch spacing must allow clearance for valve handwheels, electric actuators, pipe flanges, and thermal insulation jackets (150–400 mm c-c).
| Specification Field | YONGFAN Documented Range | Engineering Sizing Impact |
|---|---|---|
| Main Header Diameter | DN50 – DN500 | Larger diameter reduces internal fluid velocity (0.5–1.0 m/s) at total flow |
| Main Header Length | 500 – 6,000 mm | Scales with branch count, nozzle diameters, service spacing, and end caps |
| Branch Quantity | 2 to 12+ Nozzles | Determines header layout, supply-return mirroring, and saddle supports |
| Branch Diameter | DN15 – DN300 | Sized individually to match design flow of each zone or terminal circuit |
| Branch Spacing | 150 – 400 mm c-c | Provides required clearance for flanges, actuators, valves, and insulation |
| Working Pressure | 0.6 / 1.0 / 1.6 / 2.0 MPa | Governs shell wall thickness, dished end pressing, and flange ratings |
| Metallurgy | Q235-B / Q345R / SS304 / SS316L | Matched to medium chemistry, chlorides, potable certification, and corrosion |
| Drain & Vent Ports | DN20–DN40 Drain · DN15–DN25 Vent | Bottom drain for sediment flush; top high-point port for manual/auto air vent |
| Instrument Taps | M20 × 1.5 or G½” | Pre-machined threaded sockets for temperature gauges and pressure transmitters |
*Supplied as single vessels or matched mirrored pairs for aligned plant-room routing. Horizontal or vertical orientations supported.
Typical headers use DN200–DN400 mains with 4 to 8 branches to distribute secondary hot water to building blocks or riser zones. Operating temperature <100 °C.
Common configurations use DN150–DN300 mains with 3 to 6 branches serving AHU groups, FCU risers, or dedicated server room cooling loops.
Headers in the DN150–DN250 range balance flow among parallel modular boilers, recombining return water smoothly with minimal head loss.
Total simultaneous design flow (m³/h) to calculate required header diameter.
Flow rate, DN size, and service circuit name for every individual branch nozzle.
Working pressure class (0.6–2.0 MPa) and metallurgy (Q235-B/Q345R/SS304/SS316L).
Centerline spacing, nozzle direction, flange standard, and instrument socket taps.
YONGFAN application engineers will verify header velocity (≤1.0 m/s), generate 3D shop drawings, and provide competitive pricing.
Automated submerged-arc welding on main shells; full-penetration nozzle welds with visual and penetrant NDT inspection.
External surfaces blasted to Sa 2.5 profile before multi-coat polyurethane paint application (or primer for field insulation).
Every completed manifold is hydrostatically pressure tested at 1.5× design pressure for 30 minutes with zero pressure drop.
Every unit stamped with project code, design pressure, design temperature, material grade, and serial inspection log.
YONGFAN fabricates custom manifold main headers up to DN500 with lengths up to 6,000 mm.
The standard fabrication range spans 2 to 12+ branches, customized to project circuit schedules.
Yes. YONGFAN commonly supplies supply and return manifolds as a matched pair with mirrored branch centerlines for tidy plant-room pipe runs.
No. Standard manifolds include pre-machined instrument taps and flanged/welded stubs. Valves and gauges can be quoted separately.
Only when specifically engineered and sized for hydraulic decoupling volume. Standard distribution headers should not be assumed to decouple loops.
Q235-B, Q345R pressure-vessel steel, SS304, and SS316L are standard options depending on medium and chloride levels.
Do not size the main header from the largest branch alone; size for ≤1.0 m/s internal velocity at total simultaneous flow.
Symmetric nozzle layout does not guarantee equal flow; project balancing valves are required on individual branch circuits.
Do not apply standard manifold construction above 100 °C or 2.0 MPa without an engineered pressure-vessel review.
Ensure branch centerlines (150–400 mm) account for valve handles, actuators, and thermal insulation thickness.
Send your total flow, branch flow schedule, operating pressure, and plant-room single-line diagram. YONGFAN engineers will verify header velocity, generate 3D shop drawings, and provide submittals.
