| 摘要 |
A method of making electrolytic conductivity cells and a mandrel therefor in which the mandrel comprises a plurality of rod like sections each having at one end thereof a reduced diameter portion and a threaded stud for engaging a threaded recess in an adjacent section so that all the sections can be screwed together providing recesses along the length of the mandrel each formed by a reduced diameter portion of one section and an abutting end of normal diameter of an adjacent section. The step between the normal and reduced diameter portions of each section being undercut to provide a cutting edge. The method comprises slipping over the reduced diameter portion of each section a carbon graphite ring electrode, screwing together all the sections so that the electrodes are clamped in the recess, introducing the assembly into a mould, introducing plastics material in the mould to set and form the body of the cell and then applying pressure to one end of the mandrel to cause the cutting edges to shear off that portion of each electrode held in a recess thus leaving a smooth bore through the cell body. An alternative form of construction provides a mandrel having sections each with an internal peripheral recess at one end to hold an electrode against an abutting end of an adjacent section, moulding the cell body as above and then applying pressure to the mandrel to shear off the outer periphery of each electrode to form a smooth outer surface for the cell body. |
