ISO 4788 pdf download – Laboratory glassware – Graduated measuring cylinders.
These errors represent the maximum permissible error at any point on the scale, and also the maximum permissible difference between the errors at any Iwo points.
8 Material
The cylinders shall be manufactured from glass of hydrolytic class not lower than [1G53 in accordance with Iso 719. The glass shall be as free as possible from visible defects, and steps shall be taken in manufacture to ensure that it is reasonably free from intemal stress.
9 Construction and form
9.1 WaIl thickness
The cylinders shall be sufficiently robust in construction to withstand usual laboratory usage, and the wall thickness shall show no gross departure from uniformity.
9.2 Stability
The cylinders shall stand vertically without rocking or spinning when placed on a level surface. They shall not topple when placed empty (without stopper, if provided) on a surface inclined at an angle of 150 to the horizontal.
9.3 Base
The base may be integral, of glass or it may be detachable, of a suitable plastics or other material, and may
be either hexagonal or of other form provided the cylinder satisfies the requirements of 9.2.
9.4 RIm and spout
9.4.1 The rim of the cylinder shal be fire-polished and shall lie in a plane at right angles to the axis of the cylinder.
9.4.2 The spout 01 a Type la spouted cylinder shall be so formed as to enable the contents 01 the cylinder to be poured out In a narrow stream without spilling or running down the outside of the cylinder.
9.5 Neck and stopper
On a Type lb stoppered cylinder, the neck shall be ground to a suitable socket size, preferably selected from
ISO 383.
A well-fitting stopper of glass or suitable Inert plastics material shall be supplied. If Individually ground stoppers are supplied, each stopper, and the cylinder it fits, shall be marked with an identification number
9.6 DimensIons
Type 1 (a and b) cylinders shall comply with the dimensional requirements given in Table 1. In the case of a stoppered cylinder, the overall height0 shall be considered to be the height to the base of the ground neck (see Figure 1, Type lb).
Type 2 cylinders shall comply with the dimensional requirements given in Table 2.
10.1 Graduation
The graduation of all cylinders within ths specification thai be in accordance with ISO 384:1978. Clause 9.
Graduation pattern II In the case of Class A cylinders and Graduation pattern Ill In the cases of Class B and
Type 2 rneasunng cylinders.
10.2 Figuring
Figunng shall be In accordance with ISO 3841978, lOt
11 Accuracy testing
Testing of capacity and accuracy shall be performed an accordance with ISO 4787.
12 Marking
12.1 The following shal be permanently marked on each cylinder:
a) number indicating the noniwial capacity;
b) the symbol ml or ‘cm3’ to indicate the unit of volume;
The 1 000 ml and 2 000 ml cylinders may, if desired, be inscribed in temis of the litre in pLace of the mdliktre.
c) the inscription 20 ‘C” to indicate the standard reference temperature (but see 3.2 for a reference temperature of 27 ‘C):
d) the abbreviation “In” to indicate that the cylinder has been adjusted to contain its indicated capacitr
e) for Type Ia and Type lb cylinders, the letter ‘A” or “B’ to indicate the class of accuracy and the tolerance In accordance with Table 1:
f) the make?s or vendors name or mark;
g) In the case of a cylinder with an interchangeable stopper (Type Ib), the size number of the joint shall be marked;
h) the type of glass material, in accordance with Clause 8.
The permanence of marking may be assessed by the test methods specified in ISO 4794.
12.2 M individual identification number shall be permanently marked on each Class A cylinder intended for official verification or certification, or on the stopper and cylinder in all cases where stoppers are individually ground to fit only one cylinder.
ISO 4788 pdf download – Laboratory glassware – Graduated measuring cylinders
