... Area(%,min)Impact Test(V-notch)Test Temperature(°C)Impact(J,min)2≥ 295490-690≥ 22--0≥ 273≥ 410≥ 690≥ ... be calculted would be a little different.3. 17.5mm link chain, would be produced by 18mm steel round bar, ... T.W=7.12kg/m4. 19mm link chain, would be produced by 20mm steel round bar, ... T.W=8.76kgs/m5. 44mm link chain, would be produced by 45mm steel round bar, ...