Common laboratory equipment failures and troubleshooting skills

Date:2022-05-05 17:15:41 Thursday

Summary: Separating funnel cock won't turn? Can't open the jar stopper，conical flask? Can't pull out the thermometer on the stoppered flask? Difficult to remove dirt from glassware? Overwhelmed by the spill of toxic reagents? There will always be all kinds o......

Separating funnel cock won't turn? Can't open the jar stopper，conical flask? Can't pull out the thermometer on the stoppered flask? Difficult to remove dirt from glassware? Overwhelmed by the spill of toxic reagents? There will always be all kinds of "little troubles" in doing experiments, which are not accidents, but if there is no proper way to eliminate them, a lot of precious time will be wasted in vain.

Open the cemented glass grinding mouth

When the ground part of the glass instrument cannot be opened due to the cementation, the following methods can be taken to deal with it.

(1) Tap lightly on one side of the grinding mouth with a wooden tool, so that it gradually loosens and disengages due to vibration. For the fixed reagent bottle, the ground stopper of the separatory funnel, etc., the stopper of the instrument and the bottle mouth can be stuck at the corner of the laboratory table or wooden table, and then use a wooden tool to lighten the direction of the instrument at an angle of about 70°. Tap lightly, while rotating the instrument intermittently, and repeat this operation several times to open the grinding mouth that is not seriously cemented.

(2) It is inconvenient for knocking or knocking invalid to heat some fixed grinding mouths. The outer layer of the fixed part can be heated to make it expand and separate from the inner layer. For example, use a hot damp cloth to "hot compress" the bonded area, use a hair dryer or a swimming flame to bake the grinding area, etc.

(3) Immersion Some grinding mouths are firmly fixed due to chemical erosion, or are valuable instruments with complex structures, so they should not be knocked and heated. They can be opened after soaking in water or dilute hydrochloric acid for several hours. For example, for emergency instruments, organic solvents with strong penetration such as benzene, ethyl acetate, petroleum ether and sodium dioctyl succinate sulfonate can also be added dropwise to the gaps of the grinding mouth, so that they can penetrate and infiltrate to the adhesion parts so as to separate from each other.