BS 1734:1951

This standard BS 1734:1951 Specification for micrometer heads is classified in these ICS categories:

• 17.040.30 Measuring instruments

This British Standard relates to micrometer heads having measuring ranges of:

1. ½ in.
2. 1 in.
3. 13 mm.
4. 25 mm.

It applies to micrometer heads with rotatable spindles and with non-rotatable spindles, classed according to the following ranges of thimble diameter (dia. D, Figure 1):—

Type 1 Below 1 in. thimble diameter.

Type 2 1 in. and below 2 in. thimble diameter.

Type 3 2 in. thimble diameter and over.

NOTE Micrometer heads of the larger types with non-rotatable spindles may be supplied to special orders with dimensions approximately similar to those given in Table 2 and to an accuracy similar to that shown in Table 4

Heads for assembly with measuring or machine tools. Three types, thimble diameters below 1 in, 1 in and below 2 in, 2 in and over; measuring ranges ½ in, 1 in, 13 mm, 25 mm. Material, micrometer screw, spindle, thimble and barrel adjustments, measuring faces and graduations, dimensions and standards of accuracy.