How to Develop Moisture Analysis Methods

Many of our posts on using a moisture analyzer to check on moisture content provide examples of conducting a moisture analysis for a specific product. The importance of proper moisture content is described in our post on why moisture content matters. But how is a moisture analysis method developed?

Several analyses may be made by researchers in order to identify the parameters to apply for a specific product such as plastic pellets, sugar, body lotion and bread crumbs. Among the testing parameters to be identified are included:

• Sample size. Usually in grams, but how much should be used for the analysis?
• Sample protection. Certain products may require being placed on and/or covered by fiberglass filters.
• Drying temperature. Too hot or not hot enough may skew results.
• Drying profile. This relates to how heat is applied to the sample. Options include standard, auto, quick, … Read the rest

Why Moisture Content Matters

Moisture content, as we have pointed out in many of our posts, is important for a variety of reasons, many of which have to do with quality control, product shelf life and fair pricing.  Controlling moisture content can occur at several points along the processing line and usually involves the use of drying ovens, some of which are equipped with moisture sensing devices to reduce the percentage of moisture to target levels.  Moisture levels are set by industry and trade associations, and by government agencies.  It is up to manufacturers to verify moisture content.

Picking up on our opening sentence, an example of moisture’s effect on quality is exemplified by products as basic as sugar, table salt and bagged cement.  All three are hygroscopic – exhibiting a tendency to absorb moisture.  A target moisture standard for sugar is 11.9%, salt 4.9% and cement 0.8%.  We all know what happens when … Read the rest

Use a Portable Halogen Moisture Analyzer to Save Money

The compact, portable IL 50.001 halogen moisture analyzer
The compact, portable IL 50.001 halogen moisture analyzer

If you perform moisture analysis at more than one location in your facility you’ll soon see the value in the IL 50.001 halogen moisture analyzer now available from Tovatech.  What makes it attractive is its portability – instead of buying multiple halogen moisture analyzers simply pack the IL 50.001 in its custom carrying case and take it to the test location.

Moreover, you’ll find this 50 g capacity moisture balance easy to use because programming choices have been confined to the basics – a feature that has a side benefit in terms of attractive pricing.

Superior Performance in a Halogen Moisture Analyzer

Attractive pricing is not at the “expense” of superior performance in this compact, 5-pound 120-volt moisture analyzer.  Only 6.5” wide, 11” deep and 5” high, it offers the following performance specs:

  • Readability: 0.001 g, 0.01% moisture
  • Repeatability: 0.3% (3 g
Read the rest

How to Set Up a Moisture Analyzer

Operating a moisture analyzer is a quality control process across industry and plays a critical role in processing materials for ultimate use.  Moisture in this context refers not only to water but also to any volatile substance, the presence or absence of which is important in quality control.  It can be reduced simply to the question: Are you paying for water or product?  The amount of water, or the moisture content, in products works both ways and is often regulated as a quality control measure.  As one example, manufacturers can “pad” the weight of their product by increasing moisture content.  Consumers should know what they are buying and depending on the product may or may not accept moisture content as reasonable.  That’s why labels may contain a notation such as “percent moisture” to let purchasers know how much of the weight of the purchase is contributed by water.  For manufacturers or product … Read the rest

Versatile Moisture Analyzer Displays Drying Curve

Research and quality control labs looking for high-precision moisture analyzers should check out the new IL-45 halogen moisture analyzer that includes a drying curve on its display panel. With readout of 0.001g (0.01% moisture) and a maximum weight capacity of 45g the IL-45 moisture analysis balance, now available from Tovatech, quickly analyzes and displays the test identification number, % moisture, % solids, time, temperature, initial weight, and final weight.  Drying temperatures range from 50⁰C to 200⁰C.

The drying curve on the moisture balance display panel shows the progress of the analysis plotting time against percent moisture.  This helps technicians develop suitable switch-off criteria for a range of products they regularly analyze for moisture content.  For example it suggests which of the four drying methods is most applicable for a particular sample:  standard, fast, ramp or step.

Repeatability for the IL-45 is 0.05% for a 3g sample and 0.015% for a … Read the rest

Moisture Balance Maintenance Tips

The accuracy of a moisture analyzer depends on many factors one of which is establishing and following a maintenance program.  This also has the distinct advantage of protecting your investment in a precision moisture balance.

Above all, keep your Moisture Analyzer Clean

Ideally your moisture analyzer will be permanently positioned in a protected area away from drafts, dust and temperature extremes that can affect accuracy and repeatability.   But such ideal conditions may not always be available.

Moreover, when conducting moisture analysis samples invariably will fall off the moisture balance sample plate and into the equipment itself.  Wet samples such as coffee cream or carrot juice present other hazards.   These must be removed immediately.

Moisture Analyzer Cleaning Steps

Step one is to unplug the moister balance.   Following the manufacturer’s step-by-step procedures, you then remove the accessory parts.  In the case of the Kern model these include the sample dish, the … Read the rest

How to Calibrate a Moisture Balance

Laboratory-scale moisture analyzers use halogen or infrared heaters as part of a procedure to determine moisture content in products to ensure they are in compliance with federal or industry regulations.  As with all precision analytical scales and balances accuracy is a paramount requirement for a moisture analyzer.

In the case of moisture analyzers, two calibration processes must be performed: one for weighing accuracy and one for temperature accuracy.

Why Moisture Analyzers Must be Calibrated

It takes very little in the way of disturbances to impact the accuracy of a moisture analyzer balance.  For example, the effect of gravity is not the same everywhere on Earth, meaning that newly purchased analyzers must be calibrated on location before being used.

Moreover, changing environmental conditions in the laboratory or wherever moisture analyzers are used can impact accuracy, as can moving a unit to another location, even if it’s only to another worktable.   The … Read the rest

How to Prepare a Moisture Analyzer

A moisture analyzer is a valuable tool to help organizations maintain correct moisture content across a broad range of industries.  Optimum moisture content is set by industry trade associations and government agencies to insure efficient processing of products such as plastics and bone meal to maximizing shelf life of food and pharmaceutical products.

Moisture Content Defined

The term “moisture” generally refers to water – the percentage of the net weight of a product or material that is due to water content.  But it also includes anything that can evaporate on heating.  Examples include fats, oils, alcohol and solvents.  Most simply stated a moisture analyzer such as the Kern MLB available from Tovatech calculates moisture content by comparing the weight of a sample before it is dried on heating with the weight after the drying process is completed.  It consists of a halogen heater mounted on a precision scale.

Based on … Read the rest

How to Prepare a Sample for a Moisture Analyzer

Moisture content in a wide variety of products is an essential indicator of product quality – so essential that in many cases moisture content is regulated by government authorities. Google “moisture content regulations” and see for yourself.  A useful if not essential tool to comply with these regulations is a moisture analyzer or moisture balance.

Elegant in design and simple in principle, a moisture analyzer replaces cumbersome drying ovens with a halogen heater mounted on a precision scale.  The difference in sample weight before and after drying determines the moisture content of what is being tested.  But while the principle is simple, correctly operating a moisture balance requires careful sample preparation and programming consistent with the product being analyzed.… Read the rest

Moisture Analyzer a Critical Tool for Injection Molded Plastics

Today virtually all aspects of our lives are touched by injection molded plastics.  These versatile plastic resins in a variety of formulations perform in products ranging from toothbrushes to automotive consoles to minute surgical implants.  Because the moisture content of these plastics is so critical to performance, a moisture analyzer is an essential tool to ensure materials are within specification.

What is too wet or too dry?

Ascertaining the correct moisture content for a resin depends on what is being molded and the plastic employed. For example, a polymer manufacturer may state that the product being offered has a moisture content of 0.20 percent by weight or 2,000 parts per million.  But atmospheric conditions, humidity and other factors may cause a change, especially if the product is hygroscopic or accumulates moisture on its surface due to adsorption. Similarly, storage in areas with very low relative humidity could result in lowering … Read the rest