30 Years ago, the scientist Dietmar Leeb, working in the Swiss company Proceq team, developed a novel method of measurement of hardness of metals with a precision and repeatability similar to the of the table traditional durometer ratings, but with the advantage that this new instrumentwith a weight of 750 grams, it was portable and had access to areas of the sample in which other traditional durometer ratings could not be measured. By the physical characteristics of this method, in 1975 was named method Equotip - of Energy Quotient and tip (ratio of energy and tap)-, name with which Proceq then recorded the first absolutely reliable portable durometer of the story.

Despite the reluctance initial in the sector of the metal to a method that measured in a unit unknown so far, the value L, Leeb or Equotip method won easily over the following years subsectors of metal in which until then had not been possible to carry out systematic measures of hardness. Steelworks and foundries, manufacturers of large components and large series adopted Equotip as the instrument more precise and quick in their internal quality control measures.

In 1978, at the behest of Proceq, Dietmar Leeb published the scientific essay "New method dynamic measures of hardness testing", with which the L value became internationally known and popularized the use of Equotip method of quality control in metallic materials.

The value L is a hardness value equivalent to a constant ratio (1) that, since 1996, is standardised by the American ASTM Standardization Agency. The standard ASTM A-956, which since its adoption has undergone three revisions, was initially given the name of "method standardized Equotip for measuring hardness steel". In 2002, however, he changed his name to the generic "standard method of Leeb for measuring hardness steel", due to pressure from manufacturers of copies of the original instrument which multiplied the success and reliability of the method.

It should be noted, however, that while the expiry of the patent has allowed the emergence of some practically clones Equotip instruments in colors, denominations and method of operation, the ranges of uncertainty of these copies are much higher than the original apparatus. Proceq's EQUOTIP is the only portable durometer of measure according to Leeb method which continues to maintain an accuracy of + 4 HL measure over the entire range of hardness. The ratio of velocities of blow and setback of the instrument of impact, absolute basis of the method, is still heritage of the Swiss company, which is why the result of this hardness measure has remained constant on the same materials measured in units of four generations of Equotip that since 1975 have been sold around the world.

The software and technological progress in the last 30 years has meant that each new generation of Equotip presented revolutionary features with respect to the previous: new conversion tables of materials, ability to generate tables for own alloys, variety of instruments of impact for greater hardness scales and, since 2000, the complement of the EQUOstat clip that uses the static method Rockwell and is compatible with the original Equotip 2 control unit, which is made possible the measure on pieces fine and veneers, sensitive to vibrationsin which the dynamic procedure before delivering results too scattered.

The proliferation of copies, far from popularizing the method, has opened up some doubts in some users about his kindness, since numerous cheap appliances which have invaded the market only behave properly on the anvils and test tubes of control, but they are ineffective for hardness major or minor. In this sense, Proceq has opened several information campaigns warning about the danger of supplying their impact instruments calibrated by clones. "Afternoon or early, good ideas are copied" was the slogan with which the Swiss company warned for the first time of the emergence of instruments and spare parts ineffective, without shame, they copy names, appearances and colors of the original Equotip.

General Electric Power Energy, Aceralia, group Soluziona, ATISAE, SGS, Schindler Spain, ABB, Iberdrola, are some of the companies in our country that make use of the original Equotip of Proceq in its verification and quality control departments. For more than 30 years, the first Equotip and its second generation, with its red exagonal control unit, have been quality of measurement in steel mills, heat treatment, manufacturers of large parts and assembly lines in Spain. Since the advent of Equotip 2, with its characteristic yellow control unit, hundreds of portable durometer ratings of Proceq have helped facilitate the measurement of hardness of metals in Spain, extending its range of action to aluminium, grey and nodular castingbronzes and special alloys.

In the recent 2004 BIEMH, the seven instruments of impact traditional Equotip - D standard, the punta narrow D+15, of places of difficult access DL, of DC Interior, the pieces massive G, the tip of diamond to great hardness and and that of soft materials (c) - the instrument has been added S, with a ten times longer than the standard instrument performance, thereby Equotip reaches his 30 years as the portable durometer more versatile, reliable and copying of the sector.

See also...

• The physical principle of Equotip