SLIP GUAGE

Construction
Grades
Sets
Writing
Application
Precautions

1. What is Slip Guage Slip gauges are used as standards of measurement for checking the accuracy of measuring instruments such as micrometers, vernier calipers, snap gauges, dial gauge indicators etc. These were invented by C.E. Johannsen of Sweden, therefore, named as "Johannsen gauges Slip gauges are referred as 'Precision gauge blocks'.

2. Construction of Slip Guage Slip gauges are rectangular blocks of section 30 mm x 10 mm x thickness (as required). 'Alloy steel' is the most commonly used material for making slip gauges. They are hardened and quenched before being finished to required size. In order to obtain a very high order of accuracy in flatness and parallelism of opposite faces, the contact surfaces of slip gauges are superfinished by grinding and lapping.

3. Grades of Slip Guage Calibration Grade :This is special grade and is used for experimental work, research work and for measurement and inspection of other gauges (grades). Grade 0(Inspection Grade): This is used for tool room or machine shop inspection Grade l : Precise work such as setting up sine bars, checking gap gauges, measurement of components, tools etc. Grade ll(Workshop or production grade): For setting up machine tools, and for measurement where production tolerances are relatively wide Grade 00(Reference grade): This is used for highest precision work such as measuring Grade I and II.

4. Sets of Slip Guage Slip gauges are supplied in different sets of suitable sizes, so that, number of combinations may be obtained for building up required lengths or heights. Commonly used sets are M 45 and M 87 pieces

5. Wrining of Slip Guage Wringing is the process of sliding two blocks together so that their faces bond. Because of their ultraflat surfaces, t he atmospheric air between the two m ating surfaces of any two g uage block , s o that the blocks stick each other due to vaccum

6. Application of Slip Guage 1. They universally accepted as a “Standard of length”. 2. They used for direct precise measurement where accuracy of work piece being measure is high. 3. They used with high-magnification comparators, to establish the size of the gauge blocks. 4. They are used for checking the accuracy of measuring instruments. 5. They are used to setting up a comparator to specific dimension. 6. They are used to check a batch of components quickly and accurately.

7. Precautions while using Slip Guage When not in use, the slip gauges should be kept in their respective positions in the gauge box. Before wringing the blocks together, ensure that their faces are perfectly clean. After use of slip gauges, their measuring or contact surfaces should be made clean with solvent to remove finger marks, if any To remove grease, a clean rag soaked in petrol is first used, followed by a dry and soft cloth. Final cleaning is done by leather.