Diameter Vernier (π Ruler )

Application

The diameter vernier is used to precisely measure the average diameter of a round workpiece. It can be the substitution of a large vernier.

Product  description

1. The body of the diameter vernier is a metal strip , which has a main ruler in one side and an auxiliary ruler in another side. The minimum resolution of the main ruler is  0.5mm （or 1mm） , and The minimum resolution of the auxiliary ruler is 0.02mm(0.01mm、0.05mm、0.1mmCan be customized).

2. When in use,the average diameter of  workpiece can be directly got with the vernier reading method while encircling the diameter vernier around the workpiece.

product feature (compared with vernier calliper)

1. High precision:because the diameter is got by perimeter, sodividing error is shrinking π times reflect to the measurement results. Therefore its precision is higher than vernier calliper in measuring large diameter beyondφ500mm. Measurement of the 1000mm above, this advantage is especially prominent.

2. A Steel workpiece can be measured without the effect oftemperature. This is because the diameter vernier is thin, and its temperature can be equal to the workpiece in a short time. Another reason is that they have similar heat expansion coefficient, so the diameter vernier is almost without the effect of heat.

3. Measuring a large or quite large diameter can be easily conducted with auxiliary parts (magnetic bridges) by a single person.

4. Measurement of thin-walled parts are not easy to cause deformation of the workpiece

5. Take and keep it conveniently.

6. Low cost.

7. Disadvantages: Can’t lock while reading result and can’t measure theellipticity

Use-method

For the measuring beyond φ500mm, the user is advised to use accessories—magnetic bridges.Put the magnetic bridges on the face of the workpiece, let them at the same height of eyeballing and then cross the diameter vernier under the bridges before measuring (see the Figure bellow). Input 20N forces with each hand before reading. It can also be used to measure inside diameter for wide measuring belowφ1200mm. What you need to do is to turn around the outside diameter ruler for measuring, then to add 0.5mm to the reading result.

Figure

The suggested number of magnetic bridges 

                                                                                                magnetic bridges