Liquid Level Gauges
BL Series — Tubular Level Gauge
BLT threaded · BLF flanged · Protection support pipe
For observing liquid level, fluid colour and interfaces in normally non-pressurised, non-dangerous fluid systems. Choose a threaded or flanged connection and configure the gauge for your application. Gauge valves are sold separately.
BLT / BLFTechnical data
Application and operating limits
- Fluids
- Water, oil and other compatible chemical liquids
- Working pressure
- 5–8 kg/cm², depending on configuration
- Working temperature
- 120°C or 150°C, depending on configuration
- Glass centre distance
- Up to 2,500 mm
- FEP centre distance
- Up to 30 m
Pressure and temperature limits depend on length and materials; confirm the combination for the application. Gauge valves are sold separately.
Materials and options
- Valve material
- Stainless steel 304 / 316 or UPVC
- Tube
- DURAN® borosilicate glass or Teflon FEP
- Protection pipe
- Acrylic, stainless steel 304 or 316
- Viton seals
- −20 to 150°C
- EPDM seals
- −40 to 110°C
- PTFE seals
- −100 to 100°C
With or without ball check. Optional scale plate and yellow float; request a yellow float with your enquiry.
Dimensions and mounting
For thread type, please use unions to install the level gauge on the tank.
(Not provided)
| Thread size | ½ in | ¾ in |
|---|---|---|
| H (mm) | 67 | 69 |
| H1 (mm) | 38 | 47 |
| d2 (mm) | 30 | 34 |
| Drain | ¼ in | ⅜ in |
| Glass OD × wall (mm) | Ø13 × 2.2tØ14 × 2.2t | Ø16 × 2.5tØ20 × 2.5t |
| FEP OD × wall (mm) | — | Ø19 × 1.58t |
Use customer-supplied unions for threaded installation. G, NPT and BSPT male or female threads are available on request. A ½ in NPT male connection uses a ¼ in NPT female drain.
| Flange size | ⅜ in | ½ in | ¾ in | 1 in |
|---|---|---|---|---|
| H (mm) | 67 | 67 | 69 | 69 |
| H1 (mm) | 47 | 47 | 59 | 59 |
| d2 (mm) | 30 | 30 | 34 | 34 |
| Drain | ¼ in | ¼ in | ⅜ in | ⅜ in |
| Glass OD × wall (mm) | Ø13 × 2.2tØ14 × 2.2t | Ø13 × 2.2tØ14 × 2.2t | Ø16 × 2.5tØ20 × 2.5t | Ø16 × 2.5tØ20 × 2.5t |
| FEP OD × wall (mm) | — | — | Ø19 × 1.6t | Ø19 × 1.6t |
JIS, ANSI and DIN flange ratings are available on request. Scale plate optional.
Ordering information
Select BLT or BLF, then choose the connection and materials. Gauge valves are sold separately.
Ordering code follows the datasheet sequence. Code O denotes an optional flange connection; specify the required details with your quote request. Centre-to-centre length is in millimetres.
Specifications are general selection guidance. Confirm materials, connection standards, operating temperature and pressure with Sightflow before placing an order.