TUBULAR LEVEL GAUGES 2018-06-21T12:01:11+01:00

Tubular Level Gauges (Oil Tank Level Gauges)

Tubular level gauges, are a cost-effective method of visual liquid level indication for tanks operating at low pressures.

A basic standard tank level gauge consists of a toughened continuous section of borosilicate glass tube which is connected at both the top and bottom to an isolation valve. The connection between the valve and glass is sealed by means of a rubber gasket contained within a union on the valve.  The isolation valves used on this type of instrument are available either as screwed with union connection BSP or NPT, or they can be flanged to your request.

The standard tank gauges is compliment by a variety of other options to suit your needs.

Sight Glass Level | Options

Tubular Tank Gauge

Tank Gauge

Our standard Tubular level gauge is suitable for level monitoring on simple tanks and similar sealed vessels. The gauges are available in both carbon and stainless steel. Generally, off the shelf delivery. They can be used with diesel but please specify viton seals.

  • Simple to install, maintain and operate, cool handwheel operation
  • ½” or ¾” BSP Fittings
  • Flanged
  • Plain or Red Line Glass Tube
  • Acrylic Tube option
  • Guard Rod or Tubular Guard options to protect the tube
  • Graduation – Where a measure of the precise storage volume is required, graduated gauges can be supplied. The capacity units can either be marked on the guard tube or an engraved scale plate can be provided.
Quick Mount Tubular Level Gauge

Quick Mount Gauge

Tubular Level Gauges designed for general industrial use. The unique isolating valve and collar design, allows for maintenance of the gauge column without tools and the need to drain the tank. Available with automatic safety shut off valves and drain valve.

Suitable for a wide range of pressures and temperatures, the gauge is fitted with elastomer seals in materials to suit the required service.

Tubular sight glass design
Sight tubes are available in glass or polycarbonate. Metal protecting tubes are available in a variety of materials with optional supplementary transparent polycarbonate protecting tube.


  • Ease of installation and maintenance
    The Quickmount liquid level gauge can be installed without the use of special tools. Threaded end units are screwed into female tank bosses. The gauge collars slip over these units and are secured by hand tightening retaining nuts. ‘O’ ring sealing is used throughout. The isolating valves will allow column removal without need to drain the tank.
  • Tank calibration
    Where a measure of the precise storage volume is required, graduated gauges can be supplied. The capacity units can either be marked on the guard tube or an engraved scale plate can be provided.
  • Tank connection
    A closed circuit or open circuit pattern may be selected for the gauge.
  • Closed circuit pattern
    Direct connection from the top of the gauge to the tank can be made with a screw-down valve or a valveless unit.
  • Open circuit pattern
    The upper end of the liquid level gauge can be supplied with an automatic safety vent valve or, alternatively, a pipe union connection. The automatic safety vent valve will allow air to pass, but will seal against a liquid level. In the case of the pipe union connection design, a 10 mm o/d steel vent pipe is returned to the tank or into the tank vent pipe. Open circuit connection is only allowable when it is possible for the gauge column to extend above the top of the tank.
  • Electronic & Digital Readout
    Remote reading system and/or computer interface options provide a dual system with the advantages of both electronic and sight glass systems. Level alarms can also be implemented.
Mini Tubular Level Gauges

Mini Gauge

Mini Gauge is an effective yet simple tubular gauge. Its valve less connection ends screw directly into the vessel and commonly used for compressor lube oil tanks or small water tanks or in the case of a variety of fluids so that it can be easily supplied to the end units, seal materials, and sight tube.

If you want a tubular level gauge along with isolation valves please go through Quick mount (G22)

Easy Viewing:-
The coloured strip magnification on the sight tube indicates the level of colourless liquid

Graduation: –
When the measure of a storage volume is requisite, an engraved scale can be offered for the purpose.

Open Circuit: –
This type of oil tank level gauge is available where the bottom connection stabs in the wall of the tank. However, this is admissible only when the gauge column extends above than the maximum capacity level of the storage tank.

High-pressure version of the system: –
19 bar is the maximum working pressure of the standard gauge. But, a high-pressure version of sight glass level is up to 30 bar and can be easily available on the request.

Marine Tubular Level Gauges

Marine Gauge

The Marine gauge is designed for use within the marine and offshore industries. Due to it’s tubular design this gauge is suitable only for use with non-flammable liquids.

This gauge is commonly used for the water storage and coolant tanks on board cargo ships, tugs and military vessels.

Push-button operation
Except when a reading is being taken, the gauge is permanently isolated from the contents of the tank. To take a reading the spring loaded valve is opened by pressing a push-button. When released, the connection between the tank and gauge is automatically resealed.

Safe from external damage
Due to the design of the push-button isolation valve, no amount of damage to the gauge or external fittings on the tanks can break the liquid seals. In such an event the fluid cannot escape.

Instant dismantling and re-assembly
The gauge can be removed from the tank for cleaning or servicing while valves remain sealed and the tank remains leak-proof.

Ease of viewing
The level of colourless liquid is indicated by magnification of a coloured strip on the sight tube.

Where a measure of the precise storage volume is required, graduated gauges can be supplied. The capacity units can either be marked on the guard tube or an engraved scale plate can be provided.

Tubular Level Gauges

Push Button Gauge

Our basic push button tubular level gauges provides a very simple level monitoring solution. They offer a clear rigid PVC tube, that can be cut to any length to suit your application.

The unit is fitted with a self-closing valve.

Oil Sight Tubular Level Gauges

Oil Sight Gauge

Our Oil Level gauges are very simple tubular level gauge unit to provide level indication, primarily on oil tanks. As standard they are fitted from the base, but a double banjo fitting on top and bottom is also possible.


Moncrieff offer both hand, semi automatic and fully automatic blowing facilities. This makes us perhaps the most versatile pressed glass company. Offering volumes from a tens up to tens of thousands of units. All with the assurance of 150 years of experience.


At John Moncrieff Ltd we are equally happy dealing with large PLC as we are smaller concerns, all are treated with the same dedication to quality and customer service.


We invite you to send your enquiries. In the first instance please contact us with a drawing or sketch, outlining the usage conditions and an indication of production volumes.