Spanner had been a vital tool in engineering field even before the invention of the current machines that perform similar functions like that of the spanner. A good example of modern machines that could perform a similar function to that of the spanner is the electrically powered torquing machine which usually comes with different ranges of spanner socket sizes for the purpose interchanging it to suit different sizes of bolts and nuts and need the tightening and loosening operations. Despite this invention, the use of hand adjustable spanners had never been possible to eliminate completely in the field operations during engineering activities. It is such an important tool that constitute up to 20% of every tool box of any engineer or technician infield practice.
The use of spanner started when the engineering bodies adopted a means of making tools available to engineers for repair and maintenance purpose through the use of similar coupling devices such as bolts and nuts, screws, etc. across the globe. History has it that before the Second World War, there was no global organization that makes a decision relating to the coordination of engineering and the manufacturing activities of countries across the globe, this gave a huge disadvantage to the technology transfer and engineering advancement which ought to have started before then. It was revealed that the Germans were ahead of many nations in terms of technology in manufacturing sector and due to the reason mentioned above, most German products like cars, aircraft, and military weapons used to be hard to operate by any foreigner who is not a German due to the fact that every data and key functions were coded in German language, the same is also available in other countries such as; Russia, France, Britain, Australia, and US, such that everyone manufactures for the suitability of their country consumption such that when those product find their into another country the repair and maintenance becomes a problem due to none coordinated tools for such purpose, while some country uses hexagonal head bolts and nuts some uses star imprinted screws, while others use different permanent fixture and temporary coupling techniques until the engineering bodies adopted the general use of bolts and nuts and few another coupling device for coupling purpose across the engineering field globally.
It was at that instant that most foundry industries initiated special molds for the manufacturing of tools for the repair and maintenance of the machines according to the global standard of a coupling device in machines and spanner and screwdriver became the leading among others.
Today, the record has it that over 10,000 industries across the globe are into manufacturing engineering tools which spanner is among them.
Spanner has different sizes and lengths, depending on the size of the bolt and nut it is intended to loose, the popular sizes of spanner range from 4inch-30inch other higher ranges can be found in torque range tool. In a way of finding a solution to the numerous sizes of spanner that exists and making it easier for engineers and technicians to limit the number of tools in their toolbox, the production of adjustable spanner was developed to suit and solve the problem.
Adjustable spanner is a type of spanner with an adjustable lock to be able to obtain some ranges of inches which covers the inches that about 5 or more spanners may have separately, such spanner can be adjusted to accommodate different sizes of bolts and nuts, yet it still exists in ranges according to their sizes.
Limitations of Adjustable spanner
Though it fulfilled its purpose of development, it has been found in field practice that adjustable spanners are not good for torquing bolts and nuts that needs high tensioning and tightening. In such case their use is limited to flexible loosening and tightening of bolts and nuts such that any impact force that exceeds the limit of their function can cause the adjustable lock to break and making the adjustable spanner unusable next time.
It has also been found that both faces of the spanner cannot be used for tightening jobs, it is suitable to use the face that do not carry the adjustable lock to carry the force during tensioning or tightening than the other face, the reason is because of frequent damage and shortening life span when the adjustable face is used for tensioning.