Construction, coatings and industrial processes

Concrete sets slowly in cold weather because cement hydration slows as temperature falls. Common measures include protecting and insulating the pour, warming the materials, and using an accelerating admixture chosen for the concrete and its reinforcement. Your structural engineer should approve any admixture.

Calcium chloride is a known accelerator but can promote corrosion of steel reinforcement, which is why its use in reinforced concrete is restricted by many standards. Taskon makes Calcium Chloride and Calcium Nitrate; the choice for your structure must come from your engineer and the applicable standard.

Admixture selection and dose are set by your concrete technologist or structural engineer, tested in trial mixes and checked against the standards for your project. Taskon’s technical team can confirm its calcium nitrate grade against the specification they give you.

See Calcium Nitrate.

Cracking in plaster is commonly caused by too much water in the mix, drying too fast in heat or wind, applying too thick a coat, or an unsuitable base. Mixing to the manufacturer’s water ratio and slowing the drying usually help.

Follow the plaster manufacturer’s instructions. This page does not advise on plastering practice.

Fading and chalking outdoors is usually caused by sunlight breaking down the binder or pigments that are not lightfast enough for exterior use. It is a formulation question: pigment and binder choice for exterior exposure.

Your coatings technologist should review the formulation for exterior durability. See the paints, pigments and dyes industry page.

Hard settling in ink usually means the pigment is not properly dispersed or stabilised, or the ink is too thin or has been stored too long or too warm. It is a formulation and dispersion question for your ink technologist.

This page does not advise on ink formulation.

Adhesive that loses strength in storage may be reacting slowly in the container, absorbing moisture, separating, or stored beyond its shelf life or too warm. Check storage conditions and shelf life against the formulation’s specification.

Your adhesive technologist should test stored samples against fresh ones. This page does not advise on adhesive formulation.

Edge delamination in plywood is commonly caused by moisture getting into the edges, glue spread or pressing that was not right, or veneers that were too wet. Sealing edges and storing sheets dry help; the root cause is in the pressing process.

Your plywood process engineer should check glue spread, press time, temperature and veneer moisture. This page does not advise on resins.

Match heads that fail in humid weather have usually absorbed moisture. Moisture-resistant packaging and dry storage are the usual remedies. The match head formulation is a matter for your technologist.

Match manufacture uses hazardous materials and is regulated. This page does not advise on match head chemistry.

A drilling fluid that loses weight and viscosity is commonly being diluted by formation water or added water, losing solids, or being contaminated by the formation. The mud engineer should test the fluid properties and adjust the system.

Calcium chloride is used in some drilling and completion fluids, and Taskon publishes Calcium Chloride as supplied into oil and gas drilling fluids. Fluid design is for your mud engineer.

Faster catalyst deactivation is commonly caused by poisoning from impurities in the feed or raw materials, sintering from higher temperatures, fouling, or a change in how the catalyst is prepared. Compare current raw material lots and operating conditions with the period when it performed well.

Trace impurities in a raw material lot can poison a catalyst, so certificates of analysis that report the impurities you care about are worth requiring. Your process engineer should investigate.

Many oxidisers degrade faster after opening because of moisture, heat, light or contamination. Storing them closed, cool, dry and away from incompatible materials, as their Material Safety Data Sheet specifies, usually slows it. Whether a more stable alternative suits your process is for your engineer.

Oxidisers can be hazardous if stored with incompatible materials. Always follow the storage section of the Material Safety Data Sheet.

Declining performance in an absorption chiller is commonly caused by loss of vacuum or air leaks, fouled heat exchangers, crystallisation, a heat source problem, or a change in the working solution. It needs a qualified refrigeration technician to diagnose.

This is an equipment service matter. Taskon does not advise on refrigeration systems.