Graduated Cylinders Information
Graduated cylinders are tall, narrow cylinders that are open at the top. They are marked with regular lines to aid in determining volume, and also known as measuring cylinders. This type of labware is used to accurately measure the volume of a fluid or object. For objects, the displacement of a liquid placed in the cylinder is measured after the item is inserted.
For graduated cylinders, ASTM defines two levels of accuracy: Class A and Class B. ISO specifications address squat (low) form and tall form. Other product types include pharmaceutical, with flaring sides; and mixing, with a fluted and stoppered top.
Class A, Low form, Pharma, and Mixing
Image Credit: Small Parts, Inc.
Cylinder volume can range from less than 10 ml to over 4,000 ml.
Glass and transparent plastic are common materials. Glass cylinders have a high tolerance for heat and chemicals, but users must account for the meniscus when measuring. Plastic is less prone to breakage and can be coated to avoid a meniscus.
Cylinders are usually marked Total Contained (TC) or Total Delivered (TD). The former indicates that volume gradations are set for liquids in the labware; latter gradations account for traces of liquid that remain in the cylinder after removal.
Features and Applications
Bumpers or guards surround the upper portions of glass cylinders to protect them when toppled. Wide bases, either formed from the cylinder material or as separate attachments, promote stability. Cylinders sometimes have pigment stripes to aid measuring. Non-mixing cylinders feature spouts for easy pouring. Mixing cylinders come with sealable tops and stoppers. Pouring and carrying can be aided by handles.
Small Parts, Inc. and U.S. Plastic Corporation