GAUGES

A gauge is a device that makes measurements and displays the information

Pressure gauges:

Increase and decrease in pressure are measured by the pressure gauge. Pressure gauges are available in variety and add to safety and quality of life.

Air Pressure gauges:

These gauges measure the amount of air that is required to maintain the optimum use of objects having gas. This gauge consists of a container having air called a tire. This gauge maintains the correct amount of air in a tire. A little amount of air makes it flat while too much air wears it.

Hydraulic pressure gauge:

These gauges are applicable where mechanical vibration or pressure pulse occurs. These are filled with liquid usually glycerine which gives the display by the movement of the pointer. These are highly reliable and long service life.

Differential pressure gauge:

A differential pressure gauge measures the difference between two pressure points. An example of this gauge is a U-tube manometer. The two entrance ports are connected to one monitored pressure capacity. The difference between two ports is measured, this eliminates the work of the operator of checking two pressure and calculating their difference.
 
Digital Pressure Gauge:

This gauge displays the pressure in numerical value. Conversion of pneumatic or hydraulic pressure in readable signals takes place. It is used in many applications like pharmaceuticals, automotive, food processing, etc.

Diaphragm Pressure Gauge:

Diaphragm Pressure gauge consists of diaphragm or membrane which are expandable. The gauge is made up of a diaphragm that divides the capsule, the diaphragm is open to targeted pressure and another side is connected to a known pressure. The deformation of the diaphragm gives the pressure difference.

Bourdon Pressure gauge:

Pressure gauges are ideal for the hard conditions and the resulting high demand for pressure measuring in production facilities in the chemical industry and other comparable branches. Resistance to aggressive media and environments is achieved by using high-grade material such as stainless steel both for the measuring system and the casing.
The glycerine filling on these gauges ensures smooth pointer movement and thus good readability even in extreme load and strong vibration conditions. The lubricating effect of the glycerine also provides protection against increase wear.
The modem modular construction system with welded construction sealing system, tried and tested for many years, ensures a high level of functional safety and strong long services life.
 
Electric Contact Pressure Gauges:

Contact pressure with electrical alarm contacts is suitable for controlling or regulating process sequences. The contact opens and closes electrical circuits in relation to the position of the pointer on the pressure gauge.
Our contact pressure gauges with the bourdon tube system are used at process pressures of approximately 1kg/cm2 (14.22 psi) and upwards. The materials used make the gauges suitable for chemically aggressive gases or liquids, although these may not be too viscous or be susceptible to crystallization.
The inexpensive tried and tested Bourdon tube system coupled with modern modular principle provides a very reliable yet inexpensive contact pressure gauge.
Electrical alarm contact is used as magnetic snap-action contacts, especially in harsh industrial conditions. The high contact pressure and the choice of different electrical contact materials enable high currents to be switched reliably. If the electrical switching limits of the alarm contacts are exceeded or not reached, a relay is to be used to provide an appropriate current rating.
Inductive alarm contacts operate without physical contact and thus have no unfavorable effects on the pressure measuring system while having an unlimited service life. A control unit is always needed to operate these contacts. Contact pressure gauges are equipped with alarm contact can be used in explosive environments.

 
Temperature Gauges:

Temperature Gauges work on gas actuated, bimetallic or expansion principles. These gauges are able to measure temperatures between -200 (-506.2 0F) to 7000C (1292 0F)

1. Gas-filled temperature gauges:

The assembly of a Gas-filled temperature gauge consists of a stem, capillary, and Bourdon tube in an aluminium case. These parts are connected to form a unit. The complete measuring system is filled with an inert gas as standard or mercury as an option under pressure.
A temperature change causes the internal pressure in the stem to change. The deflection of the Bourdon tube thus caused is transmitted to the pointer by a movement. A bimetallic element is fitted in between the moment and bourdon tube to compensate for fluctuations of ambient temperature at the case.

Fig: Gas-filled temperature gauge

2. Bimetallic thermometer:

The bi-metallic thermometer is a quick-reacting bimetal coil. It is manufactured from two cold-welded metal strips with different thermal expansion coefficients and rotates in proportion to temperature. The rotary movement is conveyed to the pointer with low friction. A comprehensive range of the standard version enables a wide range of applications and uses. Special versions are also manufactured to the customer's specifications.

Fig: Bimetallic Thermometer

Applications, where temperature gauges are used, are:

• Petroleum industries
• Thermal / Hydro Power Stations
• Heating and Ventilation
• Food Process Industries / Hygienic Applications
• Water treatment plants
• Iron and Steel Industries
• General Mechanical Engineering Industries
• Rubber Molding / Processing Plants
• Chemical Process industries
• Air-conditioning

 
3. RTD’s

Resistance Temperature Detector (RTD) used for temperature measurement - 50(-580F) to 400 0C (7520F). The system accuracy begins with proper primary sensor selection.
Various considerations apply to the design of RTD assemblies. The element should be protected from shock and vibration, yet free of expansion stresses that may shift the reading. The element assembly needs to be isolated without obstructing heat flow. The outer sheath has to withstand pressure, erosion and vibration, yet it should be small enough for easy installation and rapid response to temperature changes.

Fig: RTD