The purpose of the packing cases is to seal (dynamic sealing) any residual gas coming from the cylinder along the piston rod.
Rod pressure packing designed to-mesure
CASTANET packing units are manufactured “to-measure” to meet to all conditions of service (up to 2500 bars). These assemblies are designed according to the nature of the gas, the discharge pressures and temperatures as well as the linear speed and stroke of the piston rod, all of which contribute to the dissipation of the heat generated.
Different designs are proposed :
with leaked gas recovery (venting), mainly for process gases (inflammable, sour, toxic, wet or costly gases).
with (lubricated packing case) or without lubrication (dry packing case) according to the process specifications or as requested by the user.
with internal cooling. The cooling of the packing cases is particularly recommended when working dry or at very high pressures.
with inert buffer gas (in accordance to API 618 ), to minimize residual leakage of the process gas. The packing case is equipped with a chamber into which is introduced an inert gas (usually nitrogen) at a higher pressure than the venting pressure.
with inert purge gas (in accordance to API 618 ). This alternative is based on the same principle as the inert buffer gas, in this case, however, the packing case has an inert gas inlet and outlet (there is only an inlet for the buffer gas).
with oil recovery in the case of combined packing cases.
With oil recovery in the case of combined packing cases
Packing cases with labyringth sealing rings (Double or triple circle packing rings)
Main functions of rod packings
