Water Spray Nozzle

Function

Correct nozzle spray angle — typically 65° or 80° full fan — ensures that coverage from adjacent nozzles overlaps without leaving dry zones in the aggregate pile. Low-flow or off-angle nozzles create moisture inhomogeneity that shows up as dry pockets in the WMM batch, causing density failures in the finished road layer. Nozzle operating pressure is typically 1.5–4 bar; deviation from design pressure due to a failed pump or blocked orifice should trigger a feed-stop alarm in the plant PLC.

Construction & quality

Body: 316L stainless steel, CNC-machined from bar stock for resistance to minerals typically present in site water supplies. Orifice insert: sintered tungsten carbide as standard for maximum erosion life; stainless steel orifice available as an economy option. Spray pattern: flat fan, angle marked on the body hex. Connection: BSP or NPT ¼ in or ⅜ in male thread with metal face seat (no fibre washer required). Each nozzle is supplied with an 80-mesh stainless steel in-line strainer to protect the orifice from particle blockage. Flow rate at rated pressure is marked on the body for field identification.

When to replace

• Spray pattern deflecting more than 10° from the nominal stamped angle
• Flow rate drifting more than ±10% from rated at constant supply pressure (orifice erosion)
• Visible mineral scale or particle deposit bridging the orifice
• Spray plume showing large droplets or water columns rather than a fine mist (partial blockage)
• Plant water consumption rising above the OMC set-point without a mix design change (leaking seat)