bondohuratsukusu null for sabuma - jia - ku welding

摘要

PURPOSE:To maintain good welding workability for a long period even after repetitive use by setting the air permeability measured by a specific method at a specific value. CONSTITUTION:A method for measuring the air permeability is executed by putting a flux to 50mm height into a cylindrical air permeability tester having 40mm inside diameter. The value when the pressure of the air generated between the air introduced above the flux layer upon passing and discharging of 2,000ml air through the flux layer at an ordinary temp. and the air passed and discharged through the flux air attains the specified value as well as the time required for discharging of the air are measured. The value of the air permeability P calculated by the equation is made =200. In the equation, P: air permeability, V: the quantity of the passing air ml, h: the height of the flux layer cm, p: air pressure (water column cm), A: the sectional area of the flux layer cm2, t: the time required for passing of V (minute).