Glass Tube Level Gauge
A glass tube level gauge is the simplest level indicator, showing the liquid level directly through a transparent tube between two fittings connected to the tank’s upper and lower ports. It needs no power or moving parts and is an economical solution for low-pressure tanks.
Borosilicate glass and acrylic (Plexi) tube types are available; fittings are nickel-plated brass as standard and stainless as an option. The store range includes a 1.5 m glass tube with ½” connection and a ½” adjustable level valve.
Main Applications
- Atmospheric water and fuel tanks
- Chemical dosing tanks
- Lubricating and hydraulic oil tanks
- Simple process and break tanks
Technical Data
| Tube material | Borosilicate glass or acrylic (PMMA) |
|---|---|
| Standard fitting | Nickel-plated brass (glass), plastic (acrylic) |
| Optional fitting | Stainless steel |
| Connection | ½” (product range) |
| Glass tube length | 1.5 m (product range) |
| Acrylic tube temperature | Usually around 60–70 °C |
| Pressure | Low-pressure tanks (by model) |
| Option | Capacitive level contact; adjustable level valve |
Material Options
| Part | Glass tube | Acrylic tube |
|---|---|---|
| Tube | Borosilicate glass | Acrylic (PMMA) |
| Fitting | Nickel-plated brass | Plastic |
| Impact resistance | Low; guard cage recommended | Higher than glass |
| Chemical resistance | Resists many chemicals | Sensitive to some solvents |
Which material? As a glass tube is sensitive to impact, use it with a guard cage or shield, and fit cocks that can shut off the liquid if the tube breaks. Reflex or magnetic indicators are preferred on pressurised and hot boilers.
Advantages
Simplest Reading
- Liquid seen directly
No Power
- No moving parts
Economical
- Low-cost solution
Easy Renewal
- Tube replaced separately
Construction and Design Features
- Transparent glass or acrylic tube
- Upper and lower fittings
- Shut-off cocks against tube breakage
- Guard cage (optional)
Write the tank centre-to-centre distance and liquid type; we will confirm the glass tube and fittings in the right size.
How to Choose?
- Assess the pressureUse a glass tube on low-pressure tanks and a magnetic indicator on pressurised vessels.
- Choose the tube materialPick glass or acrylic by chemical and temperature.
- Measure the lengthCut the tube to the distance between fittings.
- Add protectionPlan a guard cage against impact.
Complementary Products
Why ORFA?
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Details →Float Valves
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Details →Get a quote for your project
Our sales team will prepare the best solution for your needs.