Gauge Blocks are staple reference gauges used in Quality Rooms, Calibration Laboratories, Shop Floors and Machine Shops. Right from the invention of gauge blocks in 1896 they have been the major source of standardization of length for various industries. A Gauge Block or Slip Gauge is a block with opposite faces lapped precisely flat and parallel with a defined length, they come in sets of blocks of various lengths.
Gauge Blocks were first manufactured as a production-type GO/NOGO gauge. The inventor of Gauge Block, Carl E. Johansson a Swedish machinist, also developed numerous accessories that allowed Gauge Blocks a wide range of applications on the shop floor. The final patent application submitted by C.E Johansson, dated Jan 30, 1904 in Sweden.
In 1899 the Stockholm Munitions factory purchased the first gauge block set ever sold, consisting of 103 steel blocks. This set is now in the possession of AB C.E Johansson in Sweden. Modern Gauge Block sets are practically identical to his original set.
What are Gauge Blocks made up of?
Mostly Gauge Blocks are made up of steel, carbide or ceramic. These specific materials were chosen because of their hardness since they will not wear easily and produce accurate results during wringing of slips. For years now, the highest grade of Gauge Block has been the primary standard of length in industries.
What is the purpose of Gauge Blocks?
A Gauge Block is one of the oldest high precision equipment’s used in dimensional metrology and are used to calibrate other high precision instruments like Calipers, Micrometers, Height Gauges, Snap Gauges etc. When these equipment’s are calibrated using Gauge Blocks, they can achieve fine tolerance limit. Gauge Blocks ensure that tolerances of the range 0.001 mm to 0.0005 mm can be measured accurately. In recent times there are also Long Gauge Blocks and Angle Gauge Blocks introduced into metrology to make the measurements efficient and easy to use.
What is wringing of Gauge Blocks and why is it important?
Though this idea was and still is, a unique feature of Gauge Blocks, wringing is a natural phenomenon for which no one can claim ownership. The finely lapped surfaces ensured that two slips can be wringed tightly together. Wringing is the process of sliding two-gauge blocks together, so that their faces adhere tightly and act as a single block. This phenomenon occurs when the molecular attraction between perfectly flat surfaces is brought in contact with a pressure, it is not because of any magnetic attraction. Gauge Blocks are wringed to achieve a particular size.
What are the different grades of Gauge Blocks?
Gauge Blocks can be available in the following grades: K, 00, 0, 1, and 2. Grade K is used as a reference gauge, and grades 00 and 0 are used in calibration laboratories and quality rooms. Grades 1 and 2 are not as accurate, if compared to grade K, 00 and 0, hence they are used in the shop floors. Gauge Blocks of these grades are both available in Inches and Metric.
How to maintain Gauge Blocks?
Once used, Gauge Blocks should be cleaned with a soft cloth or chamois leather to avoid any scratches on the measuring face and they need to be stored with a protective coating, for example, Steel Gauge Blocks are lubricated with oil or grease to avoid rust formation. While handling Gauge Blocks, one should always wear gloves; they protect the blocks from corrosion and prevents any transfer of temperature between the handler’s body and the block. Gauge Blocks are calibrated at 20°C since it mitigates the thermal expansion, thus that temperature needs to be maintained.Â
Generally, Gauge Blocks are used regularly and should be calibrated at least once every six months. They can be calibrated by using laser interferometry or by comparison method.
Changes in technologies are taking place every second. For over a century, Gauge Blocks filled a critical need for inexpensive and flexible length gauges. Now with the advent of high precision, long range measuring technology is changing the way Gauge Blocks are used but no one will ever doubt the integrity of the results given by a Gauge Block.Â
For any information about premium quality Gauge Blocks feel free to contact Bombay Tools Supplying Agency at info@btsa.in. Bombay Tools Supplying Agency Private Limited is a pioneer in the field of metrology and inspection gauges and are currently engaged in manufacturing, marketing, calibrating, repairing, servicing, importing, and exporting instruments of world-renowned brands.
