Italian
EnglishCOPPER BAR THREAD
Copper bar thread. As already mentioned for the sheet metal, it is possible to define “thread” the particular mechanical working that is made on a cylinder or on a hole and which consists in making a groove with a helical shape, in such a way as to allow the mechanical coupling of two bodies.
Despite the enactment of rules on the world standardization of threads, made by international government bodies, to date there are several types, diversified mainly for the mechanical task they have to perform:
1) The ISO metric screw thread – in fact it is a triangular profile thread with an angle of 60° – non-sealing.
2) The Withworth screw thread – very similar to the ISO metric one, but which has an angle of 55° and foresees the mechanical contact between the bodies both on the sides and on the ridges – sealing.
3) The unified thread (in inches) with smoothed edge and connected bottom.
4) The BA screw thread with triangular edge and connected bottom to large radiuses – walls at 47°30’
5) The American Standard screw thread with smoothed edge and bottom – walls at 60°
OUR WORKING OF COPPER BARS THREAD
Our working. It is possible to make the copper bars thread through many procedures. The most common are:
– by pressing;
– by removing shavings.
The thread is generally made by forcing the screwing of already threaded, hardened and specially shaped tools on the cylindrical surface on which we work. Our company practices metric threads on holes through two distinct working methods, according to the morphology of the copper surface to be worked:
• the thread made by rolling with a TRUPUNCH 3000 punching machine. In both cases a pre-hole whose diameter is the one written in the relevant tables must be done.
• the thread made by removing the shavings, with the aid of a column electric threading machine.
