Series-DR4

Supported Applications

The Dwyer Series DR4 High Flow Glass Flowmeters provide a direct reading solution for fluid flow indication at higher capacity levels. Designed to withstand harsh industrial applications, these variable area meters are configured with permanently fused ceramic scales and integral float guides.

• Measurement of compatible gases or liquids
• Dedicated air (scfm) and water (GPM) scale options for direct reading without conversion
• Industrial environments requiring durable glass construction with safety blow-out back panels

Operating Conditions & Performance

The Series DR4 operates within specific temperature, pressure, and accuracy envelopes defined by the series specifications. The meters feature a 10:1 turn-down ratio and utilize reflective plastic backgrounds with 1.5X magnification lenses to reduce eye fatigue.

• Accuracy: ±10% FS @ 70°F (21.1°C) and 14.7 psia (1 atm absolute)
• Repeatability: ±0.25% of scale reading
• Temperature Limits: 250°F (121°C)
• Pressure Limits: 200 psig (13.8 bar)
• Mounting Orientation: Vertical mounting required

Measurement Ranges

The series supports the following flow ranges for air and water on a 127 mm scale length:

• Air: 0.2-4 scfm (5-120 SLPM), 0.5-11 scfm (20-320 SLPM), or 1-16 scfm (20-500 SLPM)
• Water: 0.1-2 GPM (0.5-8 LPM), 0.2-4 GPM (1-16 LPM), or 0.5-5 GPM (1-22 LPM)

Configuration Options

The Series DR4 is configurable across valve options, wetted materials, and scale types to match specific process requirements.

Housing and Valve Options

• Without Valve: Models available with Brass or 316 SS end fittings (e.g., DR4101, DR4201)
• With Valve: Standard configuration includes a 6-turn needle valve; models available in Brass or 316 SS (e.g., DR4141, DR4241)

Wetted Materials

• Flowtube: Borosilicate glass
• Float: 316 SS
• Float Stops: PTFE
• End Fittings: Brass or 316 SS (depending on model selection)
• O-rings: Buna-N on brass models; fluoroelastomer on stainless steel models

Scales and Connections

• Scale Type: Direct reading 127 mm scales for air or water (add suffix "M" for metric scale)
• Process Connection: 3/8" female NPT

Key Product Differences

The Series DR4 model numbering distinguishes between valve inclusion and material construction. Models ending in specific digits correspond to the flow range, while the prefix indicates configuration.

• Brass Construction: Identified by models such as DR410X (without valve) or DR414X (with valve).
• Stainless Steel Construction: Identified by models such as DR420X (without valve) or DR424X (with valve).

The series includes a safety blow-out back panel for additional protection. Care must be taken during installation to avoid sudden pressure surges, which can damage the meter if exposed directly to full line pressure.