Frequently Asked Questions
Because our filter products are made of high-quality borosilicate glass, they have a maximum operating temperature of 450°C.
The heating/cooling rate should not exceed 8°C/min. We recommend that when filtering hot substances, you observe the thermal shock resistance and, if necessary, preheat the filtration apparatus in a drying cabinet. Wet filtration apparatus should be heated slowly up to +80°C and dried for one hour before increasing the temperature further.
Glass filters are classified in porosity classes according to their nominal maximum pore size. The porosity is shown either as numbers e.g. 0 to 5 or as letters, for example, EC for extra coarse. Keep in mind, the specified pore sizes relate to the largest pore in the plate. This specification also characterizes the minimum nominal size of particles which may be retained by filtration.
We’ve made it easy. Vessels and lids can be matched using their DN (nominal diameter) number.
Yes, all of our flat flange components are suitable for use under absolute vacuum (-1 bar). Many are also rated for positive pressure operations. Be sure to check the glass surface for damage such as scratches, cracks or nicks, prior to every use. Damaged glassware should not be used due to safety reasons.
Proper care of chemistry glassware is essential. We recommend that it be washed by hand in a soaking bath or by machine in a lab washer. We also suggest that you wash laboratory glassware before it is used for the first time. In addition, lab glassware should be washed immediately after each use at low temperature, on a short cycle, and with low alkalinity.
In principle, a distinction is made between product and reflux condensers. If the condensate is to be discharged as a product, condensers is selected, for example, the Liebig cooler. If, on the other hand, the vapors are to be condensed and returned to the distillation flask, reflux or intensive condenser should be selected. For both types of condensers, in addition to the coolant temperature, the size of the cooling surface is an important consideration because the amount of heat that can be transferred is proportional to the surface area of the cooler. Large cooling surfaces are achieved by special shapes such as cooling spirals.
Glass items with ground components are characterized by a precisely fitting ground surface. Two matching ground components can be easily separated by greasing the ground surface or using a PTFE sleeve. Ideally, if the ground component is used in a high-vacuum application, an appropriate high-vacuum grease should be used.