Flow Control
S-925-M-516-WA-A
Brooks Instrument / R-12M-127-3F Model 1305 Size-12 Glass Metering Tube
About this part
Brooks Instrument S-925-M-516-WA-A is a size-12 glass metering tube for the Model 1305 O-ring-seal variable-area flowmeter. It cross-references to R-12M-127-3F and NSN 6680-01-221-5934. Brooks documented a 127 mm (5 in) scale and separate 35 GPM and 50 GPM water float selections for this tube. The tube identifier alone does not establish the installed float, scale, calibration, or complete meter construction
Configurations vary. Verify the exact unit before choosing a replacement.
No archived photo available
Key Facts
Specifications
| Manufacturer | Brooks Instrument |
| Component type | Glass metering tube |
| Brooks tube cross-reference | R-12M-127-3F |
| National Stock Number | 6680-01-221-5934 |
| Compatible end item | Brooks Model 1305 O-ring-seal variable-area flowmeter |
| Meter size | Size 12 |
| Scale length | 127 mm (5 in) |
| Material | Borosilicate glass |
| Documented water full-scale selections | 35 GPM or 50 GPM, selected by the installed float |
| Pressure drops | 27 in. W.C. at 35 GPM; 73 in. W.C. at 50 GPM |
| Maximum working pressure | 75 psig at 250°F (121°C) |
| Operating-fluid temperature | 33°F to 250°F (1°C to 121°C) |
| Ambient temperature | 33°F to 125°F (1°C to 52°C) |
| Process connections | 1-1/2 in. female NPT |
| Standard orientation | Vertical inlet and outlet; flow from bottom to top |
| Approximate overall dimensions | 14-1/16 in. high × 3-3/8 in. wide × 3-3/8 in. deep (357.17 × 85.73 × 85.73 mm) |
| Standard flow accuracy | ±10% of full scale from 100% to 10% of scale reading |
| Optional flow accuracy | ±5% of full scale from 100% to 10% of scale reading |
| Repeatability | 1% of full scale |
Model 1305 Size-12 Configuration Boundaries
R-12M-127-3F identifies the size-12 tube, while the float, scale, and material codes determine the complete meter configuration.
| Field | Documented choices | Interpretation |
|---|---|---|
| Float | 6C: 35 GPM; 7C: 50 GPM | The tube can be used with either documented water range; the exact range requires the installed float and scale. |
| Material code B | 316 stainless-steel fittings; Viton O-rings; aluminum side plates | Complete-meter option, not encoded by S-925-M-516-WA-A. |
| Material code C | 316 stainless-steel fittings; Viton O-rings; stainless-steel side plates | Complete-meter option, not encoded by S-925-M-516-WA-A. |
| Material code D | 316 stainless-steel fittings; Buna O-rings; aluminum side plates | Complete-meter option, not encoded by S-925-M-516-WA-A. |
| Unavailable size-12 material codes | A and E | Brooks marked the brass-fitting selections unavailable for size 12. |
| Alarm accessory | Not available for size 12 in the July 2013 table | Models 6221 and 6222 were documented only for sizes 8 and 10. |
Replacement and Retrofit Note
Brooks identifies the GT1600 Series as configurable to retrofit GT130x instruments. This establishes a manufacturer-supported replacement family, not a universal one-for-one substitute for this tube. A replacement meter must be configured for the required flow range, process fluid and conditions, connection geometry, wetted materials, seal compatibility, and mounting arrangement.
Glass-Tube Safety
- Keep the protective sleeve over the glass tube and secure the meter windows.
- Mount the Model 1305 within 6 degrees of true vertical, with the inlet at the bottom and outlet at the top.
- Avoid pressure and flow surges, and do not service the meter while pressurized.
- Do not use the glass-tube meter with toxic fluids or media that chemically attack glass, including steam, alkalis, fluorine, hydrofluoric acid, molten metal, or water above 140°F.
Documentation Downloads
Local PDF copiesPart Photos
0 imagesHistorical archive images for identification, labels, connectors, and condition reference, not current inventory.
Historical Listings & Prices
Historical listing data, not a current offerThe typical recorded price range is $89.99 to $89.99. Based on 1 archived listing record; not a current offer, appraisal, or confirmed sale price.
View archived listing titles
- BROOKS R-12M-127-3F S-925-M-516-WA-A O-RING SEAL FLOWMETER FLOW INDICATOR