Heavy-Wall Glass Desiccators

A desiccator is a sealed glass chamber that maintains a dry atmosphere over a desiccant (such as silica gel), used to dry samples and to keep dried or hygroscopic materials from reabsorbing moisture from the air. A perforated plate holds the samples above the desiccant, and a greased ground-glass flange seals the heavy lid.

Vacuum desiccators add a stopcock in the lid so a vacuum can be drawn, speeding drying and lowering the achievable humidity — useful for stubbornly damp or heat-sensitive samples that cannot simply be oven-dried.

Drying samples over desiccant, storing hygroscopic materials, cooling oven-dried samples before weighing, and supporting gravimetric and moisture work, in pharma, food, analytical, materials and electronics labs.

A heavy-wall borosilicate 3.3 chamber with a flat ground-glass flange and a matching lid (sealed with a thin film of desiccator grease), a knob for lifting, and a removable perforated porcelain plate above the desiccant well. Vacuum versions add a stopcock, often PTFE, in the lid for evacuation.

Keep fresh desiccant in the well and a thin, even film of grease on the flange for a good seal; slide (do not lift) the lid to break or make the seal. For vacuum use, only a properly rated vacuum desiccator should be evacuated, and it should be shielded, since a heavy evacuated glass chamber stores energy and can implode if flawed. Let hot samples cool slightly before sealing in.

Formed from heavy-wall borosilicate 3.3, with the flange and lid precision-ground to a matched, sealable fit, then annealed — important for thick glass under vacuum. The porcelain plate is a separate component. Flange fit, wall integrity and (for vacuum types) the ability to hold vacuum are the key checks.