Series-SFI-100

Supported Applications

The Dwyer Series SFI Midwest Sight Flow Indicator is designed to display flow or contents in pipelines. The series supports compatible gases and liquids across window viewing styles (SFI-100, SFI-300) and tube viewing styles (SFI-400, SFI-700). Specific configurations include single-window units with rotating impellers, double-window models with rotating impellers or flappers, and glass-tube constructions offering flow visibility from any angle.

Operating Conditions & Performance

The series accommodates a range of process temperatures and pressures depending on the specific model family. The SFI-100 and SFI-300 window styles operate up to 200°F (93°C), with limits reduced to 120°F (48°C) for models using the W2 option or 170°F (77°C) on I1 options. The SFI-300F flanged series is rated to 200°F (93°C). Tube-style indicators show different limits: the SFI-400 supports up to 200°F (93°C), while the SFI-700 operates up to 212°F (100°C).

Pressure ratings vary by construction. The standard SFI-100 and SFI-300 models are rated for 125 psig (8.62 bar), with "MP" models supporting 150 psig (10.34 bar). Flanged SFI-300F units handle up to 150 psig (10.34 bar). The tube-style SFI-400 is rated for 50 psig (3.45 bar), and the SFI-700 supports pressures up to 230 psig (15.86 bar).

Configuration Options

The series offers extensive configuration options across body materials, viewing mechanisms, process connections, and gasket types.

• Body Styles: Available in single-window (SFI-100), double-window with impeller or flapper (SFI-300, SFI-350, SFI-360), glass tube (SFI-400, SFI-700), and flanged window styles (SFI-300F).
• Materials: Bodies are offered in Bronze, 316 SS, Carbon steel, Cast iron, or Brass. Wetted materials include Tempered glass, Borosilicate tube, Buna-N, Fluoroelastomer, PTFE gaskets, and indicators made of ABS, Acetal, 304 SS, or 316 SS.
• Connections: Threaded options include Female NPT, BSPP, and BSPT. Flanged connections are available for SFI-300F (raised face) and select SFI-400 models.
• Sizes: Connection sizes range from 1/4 inch to 6 inches depending on the series type.

Special options include Plexiglass windows (W2), PTFE gaskets (G1), Fluoroelastomer gaskets (G2), and shaft materials such as 316 SS or Monel. The SFI-700 features internal wipers that restore full 360° visibility by rotating the glass tube without disrupting flow.

Key Product Differences

The series distinguishes itself through specific viewing mechanisms and mounting constraints:

• SFI-100 vs. SFI-300: The SFI-100 features a single window with a rotating impeller, while the SFI-300 utilizes a double-window design with a rotating impeller.
• Moving Indicators: Models include variants with no moving indicator (SFI-350) or those equipped with flappers instead of impellers (SFI-360).
• Tube Construction: The SFI-400 uses borosilicate glass tube construction, whereas the SFI-700 employs tempered borosilicate tubes with a bright red Acetal rotating impeller.
• Mounting Orientation: Most window and tube styles support horizontal or vertical mounting. However, models designated as type 360 are restricted to horizontal orientation only.