Transparent Gauge Glass

Transparent Gauge Glass

John Moncrieff Ltd offers Maxos Brand Transparent gauge glass. Maxos is glass used in all leading Liquid Level Gauges.

  • Jerguson (Clarke Reliance)
  • Penberthy
  • Klinger
  • Bonetti
  • Bunki Boeki
  • Nihon Klingage

The glass can be either borosilicate (“extra hard”) or aluminosilicate glasses.

Transparent Gauge Glass after moulding is subjected to a two-sided polishing and toughening. The very specific glass types, most commonly 4.2 expansion Borosilicate Glass results in products characterized by high mechanical strength and high resistance to alkalis, acids and condensates.

Our range of standard sizes and technical information

Transparent Gauge Glass Mica


If you are working with steam, hot alkaline, or acidic solutions a mica shield is the best way to protect the integrity of your gauge glass. Over time these liquids will wear down even the toughest gauge glass causing it to eventually crack, or have what looks like a melted appearance. A mica shield helps to prevent corrosion and extends the lifetime of the gauge glass. Moncrieff provides an array of different mica shields in various sizes so you can find the purity, durability, and size that you need for your equipment or application.

Mica shields are divided into different quality groups, as well as different sizes, through a visual inspection. The mica shield that you need depends on the type of process fluid you are working with and your application. Mica shields at the highest quality level, designated by V1, are clear and flat providing the highest level of visibility as well as protection. V1 mica is not obstructed by cracks, air pockets, colors or other factors.

V2 mica shields are slightly colored, and are considered to be navy-grade quality. The most common choice of grade suitable for most applications, whilst being economical in price are V4 mica shields. These will have more noticeable discoloration, and may contain some air pockets and a slightly wavy appearance. These mica shields still provide suitable protection from steam and alkaline solutions, but have some reduced visibility.

Please contact us for additional information.

Transparent Gauge Glass | Custom Manufacture

Transparent Gauge Glass  can be produced to non standard sizes, please contact us.

Transparent (Plain) level gauge glasses are used to read the liquid level. They can be (type TA 28) used up to 180 bar / 356 ° C for aggressive environments affecting (interacting) the glass (eg. saturated steam, hot water, alkalis) and up to 300 bar / 400 ° C for soft environments. Glass must be protected from the medium side through the mica shields. They are especially recommended for environments contaminated, viscous and highly corrosive.

Depending on the width and thickness there are four basic types of transparent level gauge glasses:

  • Type A – width 30 mm, thickness 17 mm
  • Type B – width 34 mm, thickness 17 mm
  • Type H – width 34 mm, thickness 22 mm
  • Type TA 28 – width of 27.6 mm, 16.8 mm

In addition, the occasionally encountered also:

  • Type C – width of 20 mm, thickness 12 mm
  • Type D – width 25 mm, thickness 15 mm

Reflex level gauge glasses are supplied either individually or in sets with gaskets and mica if required.

Reflex Gauge Glass

Reflex Gauge Glass