Bicolor Glass Tubular Level Gauge

U-IDEAL level gauge > Glass tube level gauge > Bicolor Glass Tubular Level Gauge

Bi-color water gauge consists of upper valve, lower valve, and gauge body, blow off valve, balancing tube and lamp house. The upper valve and lower valve can be fully opened and closed by Hand. Inside the valve body. There is a safety steel ball and safety valve seat. When the quartz glass rube is broken suddenly, the steel ball will remove to the safety valve seat in high speed pushed by high pressure steam to shut off the channel of the gauge automatically until the upper and lower valves is closed by hand. The ball will be reset by the pressure from the balancing tube and by its gravity.

Measure ranges	300~3200mm
Working temperature	-20~600ºC
Nominal pressure	PN0~10Mpa
Quartz tube test pressure	≤13MPa
Meter material	carbon steel or SS304
Display	Green for liquid, red for air (don’t need electric power supply for the double color display)
flange standard	DIN，ANSI，JIS
Back light is optional	a, light Emitting Diode: electric power supply: 24VDC. b, fluorescent light tube: power supply: 220VAC

Model selection of Sight Glass Tubular Level Gauge
GZS		Pressure	temperature	Body material	Glass material	C-C distance
Type	C	Natural Color
	X	Bi-color Indicator with Lamp
	A	Bi-color Indicator without Lamp
Pressure		P1	1.0MPa
		P2	2.0MPa
		P4	4.0MPa
		P6	6.0MPa
		P10	10.0MPa
Temperature			T1	<60 ºC
			T2	<100 ºC
			T3	<180 ºC
			T4	<450 ºC
			T5	<600 ºC
Body material				CS	Carbon Steel
				304	Stainless steel 304
				316	Stainless steel 316
				PVC	PVC anticorrosive plastic
				PP	valve, flange PP anticorrosive plastic
				PTFE	Stainless steel lining PTFE
Glass tube material					Ordinary Glass Tube <100ºC
					Transparent Hart PVC anticorrosive plastic tube <60ºC
					Transparent Soft PTFE anticorrosive tube <180ºC
					Quartz glass tube a. <450ºC; b.<600ºC
Center to Center Distance						(mm)

Advantages of Quartz Glass Tube Level Gauge

1. Outstanding High Temperature & Thermal Shock Resistance

Quartz glass boasts an extremely low thermal expansion coefficient. It can work steadily under high temperature up to 1200℃, far superior to ordinary borosilicate glass tubes.
It withstands sudden cold and hot alternation during boiler flushing, startup and shutdown, and rarely cracks from temperature impact, greatly lowering glass breakage risks.

2. High Pressure Resistance & High Mechanical Strength

Compared with common soda-lime glass tubes, quartz glass has higher tensile and compressive strength. It can match medium-pressure vessels and steam equipment, supporting higher working pressure without bursting easily.

3. Excellent Corrosion Resistance

Quartz is inert to most media: clean water, steam, light oil, weak acid, weak alkali and organic solvents. It will not be eroded, fogged or etched for long-term use, keeping the tube transparent without blurred liquid level boundary.

4. Ultra-High Light Transmittance & Clear Observation

Quartz achieves over 90% visible light transmittance. No yellowing or turbidity after long service life. Operators can clearly watch liquid level, bubbles, sediment and medium stratification without auxiliary lighting.

5. Long Service Life & Low Maintenance Frequency

Ordinary glass tubes tend to form scale and become opaque quickly under high-temperature steam; quartz glass surface is smooth and hard, scale adheres weakly and is easy to clean. Its replacement cycle is 2–3 times longer than standard glass tubes, reducing spare part costs and downtime.

6. Wide Working Temperature Range

Adaptable to ultra-low temperature cryogenic media and continuous high-temperature steam working conditions, suitable for heating boilers, thermal oil tanks, deaerators and high-temperature intermediate storage tanks.

7. Safe Anti-Leakage Matching Performance

Matched with standard gauge cocks with self-sealing steel balls. Even if the quartz tube accidentally breaks, the built-in steel ball instantly blocks the pipeline to avoid hot medium spraying and scald accidents.
Brief Brochure Summary
Quartz glass tube level gauges feature superior thermal shock resistance, high temperature and pressure tolerance, strong anti-corrosion performance and high light transmittance. With long service life and clear long-term observation effect, they are ideal liquid level measuring instruments for high-temperature steam, oil and weak corrosive medium low/medium-pressure vessels