Thermocouples for Process Measurement

Industrial Thermocouples

A thermocouple is a device which functions as a temperature sensor. Two wires, made of dissimilar metals, are joined together at both ends. The thermocouple is, at this point, a thermoelectric circuit with current flowing in relation to the temperature at each junction.  The temperature of one junction is known and constant, called the cold junction. The other junction is placed in contact with the media or object to be measured. The closed circuit of the thermocouple subsequently gets broken at the center, and the open circuit voltage from the hot junction is a direct function of the junction temperature. Heating or cooling the sensing junction of the two metals produces a voltage directly correlating to the temperature.

There are a number of metal combinations used to produce industrial thermocouples. Each combination has a respective set of performance attributes, operating temperatures, tolerances, and cost that may deliver best performance for a particular use.

Common Thermocouple Types and Composition

• Type J (Iron / Constantan)
• Type K (Chromel / Alumel)
• Type T (Copper / Constantan)
• Type E (Chromel / Constantan)
• Type N (Nicrosil / Nisil)
• Type B (Platinum / Rhodium)
• Type R (Platinum / Rhodium)  

Generally, thermocouple sensor assemblies, often a tube enclosing the thermocouple junction, can be grounded, ungrounded, or exposed. The wires constituting the tip of a grounded probe are attached to the inside of the probe wall, allowing for maximal heat transfer through the probe wall to the junction while maintaining a physical separation between the junction and the measured media or object. The difference between grounded thermocouple probes and ungrounded thermocouple probes is that in ungrounded probes, the junction is not attached to the probe wall. For this reason, ungrounded probes can exhibit slower response time, but do provide electrical isolation of the junction from the housing. An exposed thermocouple will have the junction protruding from the probe tube or perforations in the tube to allow actual contact between the measured material and the junction. While this provides very rapid response, the junction is exposed to damage and wear.

Various Thermocouple Styles

Thermocouples are useful for process measurement due to their size, response, ruggedness, accuracy, cost, and wide range of available form factors. Chemical and petroleum refineries, as well as other fluid processing operations, can use multiple thermocouples to control, limit, test, log, and monitor process-related temperatures. Temperature is one of the most measured parameters in industry. Understanding the temperature range being measured, the accuracy level required, and the related process vibration concerns of each industry will aid in selecting the proper thermocouple for an application. When properly matched to the application requirements, thermocouples are a durable and cost-effective process measurement option.

Download your temperature sensor selection catalog here.

Contact Alliance Technical Sales with your temperature sensing requirement. Their application engineers will help you select the best sensor for the job.

Analytical Measurement Solutions for Optimization of Your Brewing Process

Stages of brewing and areas for process measurement.

The beer market is currently experiencing an intense globalization process, reflected in escalating competitive and cost pressures. In addition to this, there is growing diversification into new, innovative beverages that demand maximum production flexibility. The time to market is becoming ever shorter, and product quality has to be guaranteed at a consistently high level, accompanied by an increase in productivity.

In-line Measurements in the Brew House

Proper process control plays a vital role in determining the flavor, foam stability, and color of the finished beer. The relative measurement sensors are exposed to high temperatures, and solid particles and turbidity constituents, and must be capable of surviving multiple CIP cycles.

Turbidity Sensor

Measurements in the Fermentation and Storage Cellars

At standard fermentation temperatures, propagation of microorganisms is detrimental to the beer. In order to prevent this from occurring, hygienic plant design and use of materials resistant to CIP solutions are important criteria, as they are for in-line sensors.

DO and CO2 Sensors

Measurements in CIP Systems

The economic use of fresh water, as well as the multiple use of cleaning solutions, present a further basis for achieving overall cost reduction in line with the strive for greater efficiency of the brewing process. Here also, in-line systems are of help in monitoring and optimizing the relative sub-processes.

Measurements in Wastewater Treatment Facilities

Fouling of sensors in wastewater leads to uncertainty about the measurement results and can even result in measurement system failure. METTLER TOLEDO provides efficient and practical solutions in the wastewater treatment areas as well.

You can download the full "Analytical Measurement Solutions for Optimization of Your Brewing Process" brochure here, or view it in the embedded document below.

Analytical Measurement Solutions for Optimization of Your Brewing Process from Alliance Technical Sales, Inc.

A Little Shameless Self-Promotion

Comments from Alliance Technical Sales customers and principals.

Established in 2000, Alliance Technical Sales, Inc. is a manufacturers’ representative agency providing numerous process control instrumentation solutions to customers across a wide range of industries.

https://alliancets.com
630-321-9646

Electric Heaters Designed for Intermediate Bulk Containers (IBCs)

Wrap-Around IBC Tote Tank Heaters
(Briskheat)

Intermediate Bulk Containers (IBCs), also known as IBC totes, or pallet tanks, are reusable industrial containers designed for the transport and storage of bulk liquid or granulated chemicals, food ingredients, solvents,  pharmaceuticals, or other material.

Often, to maintain optimum viscosity, there is need to apply heat to the contents of a tote to raise and maintain it's temperature.  This ensures the material remains ready for production and is easy to dispense. Without external heat, increased production cost or damage to equipment can occur. Heaters are also used to protect temperature sensitive material inside the IBC tote from cold or freezing, thus reducing the possibility of loss due to ruined materials.

The most effective way to heat IBCs are with specialized electric heaters referred to as "wrap-around IBC tote tank heaters". These heaters are adjustable to fit many size totes, provide the required wattage to maintain a temperature between 50 deg. F and 160 deg. F. and also include built-in 1/4” fiberglass insulation for thermal efficiency. They can be used with caged, plastic, or metal IBC tote tanks. Installation and secure fit are accommodated with adjustable nylon straps and buckles.

As the contents of the tote empties, there is no reason to continue to heat it's upper zone, so IBC heaters include independent, dual zone temperature control that separately controls the upper and lower zones of the bottle.  A built-in high limit thermostat and a grounded heating element prevents overheating and worry-free operation. A standard 120 volt, grounded 3-prong plug is provided for easy power connection (240V models have bare wires).

Silicone Rubber IBC Tote Tank Heaters
(Briskheat)

An alternative design are silicone rubber IBC tote tank heaters, for use on totes with removable bottles. Placed inside the IBC cage, directly under, and in direct contact with the bottle, they provide very fast and efficient heat-up. Made from fiberglass reinforced silicone rubber and 1/2” thick foam padding, these heaters provide outstanding durability. This design comes complete with a grounded heating element, thermocouple temperature sensor, and digital temperature controller, and is approved for use indoors and outdoors.

Common Uses for IBC Totes:

• Lubricants/Oils
• Solvents
• Detergents
• Adhesives
• Liquid/Granulated/Powdered Food Ingredients 
• Honey/Syrup/Molasses
• Chemicals

For information on any IBC, tote, or tank heating application, contact Alliance Technical Sales by visiting https://alliancets.com or calling 630-321-9646

Features of Magnetic Level Gauges (Magnetic Level Indicators)

Magnetic Level Gauge
(Jogler)

Magnetic level gauges, also known as magnetic level indicators, are routinely used to provide a display of liquid level in tanks and other vessels. Their popularity stems from their high visibility from distances and non-invasive design which reduces the possibility of leak points and the risks of fugitive emissions.



"Mag Gauge" construction is fairly simple. A magnetic float, designed for the specific gravity of the material being measured, rides inside a vertical pipe on top of the process media. A gauge with magnetically coupled visual indicator is fastened to the pipe. As the media inside the pipe rises and falls, the visual indicator moves in the same fashion.



Magnetic level gauges are often employed in tandem with magnetostrictive, guided wave radar, or other measurement means to provide a reliable local display of liquid level, as well as an electrical signal that can be transmitted to recording instrumentation or controllers.


The features of magnetic level gauges include:

• Low maintenance. 
• Wide operating temperature and pressure range.
• Visual tank level indication. 
• Continuous level measurement.
• Easier to read from greater distance than glass sight gauges. 
• Can be applied to wide fluid level ranges with a single instrument. 
• Break resistant, sturdy.
• Wide range of construction materials available.
• External mounting of ancillary indicators, switches, and transmitters with isolation from process media. 
• No electric power required for operation.

There are a number of options available so you can customize the level indicator for each specific application.  The best way to proceed is to combine your process knowledge with that of a product specialist.  Collectively, you'll be able to achieve an effective solution to your application challenge.

Industrial Corrosion Protection Through Chemical Treatment

"An ounce of prevention is worth a pound of cure", particularly when dealing with corrosion and it's effects on process equipment. Production downtime, safety concerns, environmental damage and personnel health all outweigh the obvious repair and replacement cost of the damaged equipment. All taken, the annual costs due to corrosion are estimated in the process and power industries are estimated to be around $750 billion globally.

Exterior treatments, such as painting and specialized coatings provide satisfactory results to maintain structural integrity. However, internal protection of process equipment requires a different approach. Building equipment from exotic materials which are immune from corrosion exceed any practical concept of reasonable cost. Another, much more reasonable approach is corrosion protection based on chemical treatment.

This guide, courtesy of Mettler-Toledo Process Analytics shows you the role in-line analytics play in keeping corrosion under control and avoiding unnecessary chemicals consumption in chemical plants, refineries, power and Cogen facilities.

Your local Process Analytics specialist can help you select the best equipment and strategy. Their experience and knowledge will save you time, money, and ensure quality. 

Process Refractometers for Food and Pharmaceutical Use

Process refractometer with sanitary adapter
for food and pharmaceutical. (Electron Machine)

There are many industrial applications for process refractometers; particularly useful in the food and pharmaceutical industries, where there is a need for solids content measurement. Process refractometers are used to optimize production processes, ensure consistency and purity, and in managing quality control. Process refractometers and inline process refractometers, are types of refractometers designed for the continuous measurement of a fluid flowing through a pipe or inside a tank. They provide analysis to quickly, dependably, and to accurately identify a sample to determine its concentration and purity levels. By measuring the refractive index and temperature of flowing liquids, refractometers can then apply a mathematical function to determine the precise concentration of dissolved solids.

In commercial food applications such as jam or jelly production or the processing of soft drinks or wine, refractometers are used to measure degrees Brix. Bix is a graduated scale, used on a hydrometer, that indicates the weight of sugar per volume of solution at a given temperature. The Brix scale relates refractive index to sugar concentration, and is a method of maintaining consistency. For example, process refractometers are used for the concentration process of fruit juices. The concentration process is normally achieved by removing water through evaporation, and by measuring Brix, the evaporation process can be controlled and related to the desired juice concentration.

Process refractometers are also used in pharmaceutical processing where there is the need to monitor and control concentration levels during supersaturation, a critical process in crystallization. Crystallization is a critical element in the purification of solids in pharmaceutical production. The process refractometer guarantees precise monitoring and a high degree of measurement accuracy and reliability, towards the production of a pure product.

For more information on the application of process refractometers, contact Alliance Technical Sales by visiting https://alliancets.com or by calling 630-321-9646