B8 Reflex Gauge Level Glass with gasket

Short Description:

Style:B8 Reflex Gauge Level Glass with gasket


Gauge level glass, also can be called transparent gage glass, transparent level glass and transparent sight glass. The glass is manufactured into the strip shape with flat surface(transparent gauge level glass) or groove surface(reflex gauge level glass) for observing the liquid level of the tank, pressure vessel, boiler, etc.

Product Detail

Borosilicate glass

Aluminosilicate glass

Quartz glass

Ceramic glass

Sapphire glass

Cobalt Blue Glass

Product Tags

Gauge Level Glass

Gauge level glass, also can be called transparent gage glass, transparent level glass and transparent sight glass. The glass is manufactured into the strip shape with flat surface(transparent gauge level glass) or groove surface(reflex gauge level glass) for observing the liquid level of the tank, pressure vessel, boiler, etc.

The tempered borosilicate glass and aluminosilicate glass have lower expansion coefficient and thermal shock performance, these make the glass can be long serve in extreme operational  environment such as acids, alkalis, high temperature and high pressure.

Gauge level glass is made with high quality material and it is usually thick in order to resist aggressive environment, such as high temperature, high pressure, acid and alkali. It has clear surface to make sure the high transparency for observing the liquid level more clearly.

Because of the rust resistance feature and high transparency, the transparent gauge glass is widely used in industry, petrol, chemistry, food and medicine.

According to the medium.

Transparent gauge level glass-for no color medium.

Reflex gauge level glass-for colorful medium

Mica component units-for high corrosion resistance medium


Material A:borosilicate glass(standard)

Material B:aluminosilicate glass(high pressure)

Accessories: graphite gasket, asbestos sealing and mica

Dimensions of Gauge level glass (mm)(transparent gauge level glass, reflex gauge level glass)

Code Length Glass Size Code length Glass Size Code Length Glass Size
A0 3-3/4’’ 95x30x17 B0 3-3/4’’ 95X34X7 H0
A1 4-1/2'' 115x30x17 B1 4-1/2'' 115x34x17 H1 4-1/2'' 115x34x22
A2 5-1/2'' 140x30x17 B2 5-1/2'' 140x34x17 H2 5-1/2'' 140x34x22
A3 6-1/2'' 165x30x17 B3 6-1/2'' 165x34x17 H3 6-1/2'' 165x34x22
A4 7-1/2'' 190x30x17 B4 7-1/2'' 190x34x17 H4 7-1/2'' 190x34x22
A5 8-5/8'' 220x30x17 B5 8-5/8'' 220x34x17 H5 8-5/8'' 220x34x22
A6 9-7/8'' 250x30x17 B6 9-7/8'' 250x34x17 H6 9-7/8'' 250x34x22
A7 11'' 280x30x17 B7 11'' 280x34x17 H7 11'' 280x34x22
A8 12-5/8'' 320x30x17 B8 12-5/8'' 320x34x17 H8 12-5/8'' 320x34x22
A9 13-3/8'' 340x30x17 B9 13-3/8'' 340x34x17 H9 13-3/8'' 340x34x22
A10 14-7/12’’ 370x30x17 B10 14-7/12’’ 370x34x17 H10 14-7/12’’ 370x34x22
A11 15-3/4’’ 400x30x17 B11 15-3/4’’ 400x34x17 H11 15-3/4’’ 400x34x22
A12 16-11/20’’ 420x30x17 B12 16-11/20’’ 420x34x17 H12 16-11/20’’ 420x34x22

Features and Advantages

High working temperature and pressure

We can recommend suitable material and thickness according to your working environment. Our quartz glass can work under 800 °C temperature.

Acid and alkali resistance

Glass material is stable and the borosilicate and quartz glass can resist most acid and alkali, which expands the life time of transparent gauge glass.

High transmittance

As the glass to observe the liquid level, light transmittance is very important. Glass can meet the requirement.

Friendly to environment

Unlike plastic, glass is friendly to environment both during production and using.

  • Previous:
  • Next:

  • *Borosilicate glass

    Borosilicate Glass for circular sight glasses or tubular sight glasses
    Borosilicate glass is a kind of glass with silica and boron trioxide as the main glass-forming element. Borosilicate glasses become famous for having very low coefficients of thermal expansion, making them more resistant to thermal shock than soda-lime glass. borosilicate glass is fit to be used in sight glass lens,
    Borosilicate glass is ultra and clear glass with good thermal and chemical properties and outstanding transparent
    Dimensions(mm): 1200×600 ,1150×850 ,1150×1700.(other size upon request)
    Available thickness(mm): 1mm-25mm,we also can offer it if you want more thickness.
    Density (g/㎝3 ) (at 25℃): 2.23±0.02
    Co-efficient of expansion(α)(20-300℃): 3.3±0.1×10-6
    Softening point(℃): 820±10
    Identical temperature difference(K): 100 >300(Strengthening type)
    Maximum working temperature(℃): ≥450
    Refractive(nd ) : 1.47384
    Light transmission: 92%(thickness≤4mm;91%(thickness≥5mm)
    Circular sight glass lens
    Tubular borosilicate glass
    Appliance glass such as furnace, microwave, gas stove etc.
    Industry Glass such as sight glass, linings, etc.
    Lighting equipment (protective glass for high-power spotlights and other lamps)
    Photovoltaic module
    Optical filters
    Primary material for fully tempered glass
    Main properties
    High temperature stability
    Good surface quality
    Outstanding transparency in the visible, UV and IR ranges
    Can be tempered
    High chemical resistance
    Environmental engineering and chemical engineering (lining layer of repellence, autoclave of chemical reaction and safety spectacles);
    Our circular sight glass is required in all areas where the visual inspection of processes in vessels has to be ensured under pressure, at high temperatures or on exposure to chemicals. These sight glasses is made mainly from borosilicate glass, we also produce sight glass lens with alumino-silicate glass or quartz glass or sapphire glass

    *Aluminosilicate glass

    Aluminosilicate glass for boiler gauge glass
    Alumino-silicate glass is mainly composed of Si-Ca-Al-Mg and other alkali metal oxides through a scientific ratio combination, in which the content of K2O+Na2O ≤0.3%, belongs to the non-alkali aluminum silicate glass system, after high temperature tempering treatment with high temperature resistance, high pressure resistance, acid and alkali resistance and other excellent physical and chemical properties, is a variety of high pressure glass window excellent material.It is mainly used in power plant, petrochemical, nuclear power plant, deep-sea exploration equipment and other kinds of high temperature and high pressure steam package on the high pressure water level gauge glass window.
    Color: colorless or slightly yellow
    Shape: circular, rectangular
    Density: 2.62–2.67 g/cm3
    Transmissivity: 91.8%
    Refractive index: 1.5325 (yellow)
    Shock temperature: ≤ 370 °C
    Softening temperature: ≥ 920 °C
    Bending strength: 240–300 MPa
    Max working temperature: 550 °C
    Resistant pressure:1Mpa-32.0Mpa
    round sight glass:diameter:8mm-300mm
    Rectangle sight glass:8mm*8mm-300mm*300mm
    Linear gauge level glass:Max length 400mm

    *Quartz glass

    Quartz glass for round sight gauge glass or tubular sight gauge glass
    Normally,quartz glass is fused quartz is the widely usage in industry and home appliances.it is a glass consistant of almost pure silica in amorphous form,it’s purity up to 99.9% according to requirement.
    Softening point is 1730℃,long time work temperature 1100℃,short time work temperature 1400℃
    Shock thermal:taking out the glass from 1100℃ furnace into 20℃ water,no breakage three times.
    The visible light transmittance is more than 93%.
    Corrosion resistant:quartz glass can work in the intense acid and alkaline environment
    Synthetic Quartz Silica and Infrared Optical Quartz both used as the optical glass.

    Property Typical Values
    Density 2.2×103 kg/m3
    Hardness 5.5 – 6.5 Mohs’ Scale 570 KHN 100
    Design Tensile Strength 4.8×107 Pa (N/m2) (7000 psi)
    Design Compressive Strength Greater than 1.1 x l09 Pa (160,000 psi)
    Bulk Modulus 3.7×1010 Pa (5.3×106 psi)
    Rigidity Modulus 3.1×1010 Pa (4.5×106 psi)
    Young’s Modulus 72GPa (10.5×106 psi)
    Poisson’s Ratio 0.17
    Coefficient of Thermal Expansion 5.5×10 -7 cm/cm•°C (20°C-320°C)
    Thermal Conductivity 1.4 W/m•°C
    Specific Heat 670 J/kg•°C
    Softening Point 1683°C
    Annealing Point 1215°C
    Strain Point 1120 °C
    Electrical Resistivity 7×107 ohm cm (350°C)
    Dielectric Properties (20°C and 1 MHz)
    Constant 3.75
    Sonic Attenuation Less than 11 db/m MHz
    Permeability Constants(700°C) (cm3 mm/cm2 sec cm of Hg)
    Helium 210×10-10
    Hydrogen 21×10-10
    Deuterium 17×10-10
    Strength 5×107 V/m
    Loss Factor Less than 4×10-4
    Dissipation Factor Less than 1×10-4
    Index of Refraction 1.4585
    Constringence (Nu) 67.56
    Velocity of Sound-Shear Wave 3.75×103 m/s
    Velocity of Sound/Compression Wave 5.90X103 m/s
    Neon 9.5×10-10
    Circular sight glass
    Tubular sight glass

    *Ceramic glass

    Ceramic Glass for panel of boiler and fireplace and electric heater

    Ceramic Glass has characters: heat resistant, shock temperature resistant, strengthen, hardness, acid-resistant, alkalinity-resistant, low-expansion. transparent ceramic glass, black ceramic glass, bronze ceramic glass, salient point ceramic glass. milk white ceramic glass.

    Item Parameter
    Bending Strength 180 – 220 MPa
    Coefficient of Thermal Expansion(-50-600℃) ±8×10-7/℃
    Softening Temperature ≥ 800℃
    Work Temperature ≥ 800℃, ≤1000℃
    Shock Temperature ≥ 700℃
    Product Density 2.62 – 2.67 g / cm3
    Thickness 4mm,5mm
    Size 200*250mm,300*400mm,400*500mm,400*600mm,400*780mm
    Density 2.5±0.1g/cm2
    Process Grind edge, safety corner, bend
    Water resistant ISO719/DIN12111 HGB1
    Acid resistant ISO1776/DIN12116 3
    Alkalinity resistant IS0695/DIN52322 A2



    Panel of Boiler and Fireplace, Wave Soldering, Oven, Panel of Electric Heater, Protective Panel of Spotlight, Infrared Drying Equipment, Ultraviolet Protection Equipment, Barbecue Plate, Laboratory and High Temperature Welding Mask, Safety Glass.


    *Sapphire glass

    Sapphire glass for observation window or screen protector
    Sapphire glass is now gradually used in pressure observation window, dangerous situation monitoring instrument, deep-water pressure environment instrument and oilfield, coal mine and other occasions.
    Our sapphire glass products can be coating treatment, screen printing treatment or special heat treatment according to customer requirements, to adapt to customer’s special needs.
    Sapphire window is suitable for ultra high pressure environment.
    Compared with tempered glass and other pressure-resistant glass products, sapphire can be thinner under the same pressure environment, effectively reducing the volume of the instrument.
    Generally, sapphire can withstand 10MPa of pressure per 5mm thickness.Of course, specific application is still affected by window diameter, use temperature, flange installation.
    Our products are used by many petroleum instrument manufacturers in the oil exploitation, drilling industry, product quality is highly recognized.
    Shape molding: CNC or laser.
    Product thickness range: thickness 0.2-100mm.
    Product finish after polishing: 80/50, 60/40, 40/20 (US army standard).
    Surface parallelism: less than 20 arc seconds.

    Sapphire tube is generally used for high temperature, pressure, corrosion level observation.

    Cobalt Blue Glass

    Cobalt Blue Glass for observing flame
    Cobalt blue glass is used in steel work and cement plant observation scenarios where IR protection is not required, but observation of bright furnaces requires blue eyewear to be able to see into the furnace better.
    Cobalt blue glass is NOT a good substitute for green IR glass. Cobalt blue lenses do not protect the eyes from IR radiation like the green IR does, but cobalt blue lenses are not designed for that. Furnace observation cobalt blue glass is designed with the furnace observer in mind, and it allows those who are observing hot furnaces without IR radiation to see into the furnace so they can reduce eye fatigue and increase their vision of the items in the furnace.

    The spectrum of cobalt elements makes it incapable of absorbing blue light (i.e., reflecting or passing through blue light, while completely absorbing yellow light with different wavelengths of blue light). Blue cobalt glass filters yellow light because of the presence of cobalt ions.
    In observing the flame reaction of potassium needs through cobalt blue glass, because the potassium compounds are not pure, often mixed with some impurities, such as sodium (not easy separation), in the flame reaction, due to the flame yellow sodium, interfere with the flame reaction of potassium (purple), so you have to take yellow light filter, by the light of the principle of complementary color, yellow and blue are complementary colors. Using blue cobalt glass to filter out the yellow light, the potassium’s flame-color, purple, is clearly visible.

    Steel plant and cement plant for observing the flame color.
    Round or rectangle cobalt blue glass be installed in the observation window.
    Cobalt blue glasses.

    50mm*50mm; 50mm*100mm; 50mm*107mm,other size can be customized
    Cobalt light blue glass be used in laboratory.
    Cobalt dark blue glass be used in cement plant and steel works.
    Cobalt blue glass component:SiO2:75.01%; B2O3:0.27%; CaO:4.18%; Na2O:15.94%; K2O:1.19%;
    CoO:0.51%; Fe2O3:2.9%