A valve includes at least one valve stem seal, such as a packing seal, that is included in a removable seal cartridge. The valve stem is connected to the actuator via a linkage, which can be removed to provide a linkage gap between the actuator and the valve stem. The seal cartridge can then be slid along the valve stem into the linkage gap and laterally removed from the valve, whereupon the seals within the seal cartridge can be refurbished. The valve can be a rotary or linear valve. In embodiments, the linkage gap can be increased by linear displacement of the actuator away from the valve stem. The seal cartridge can be re-installed in the valve after refurbishment, or a substantially identical replacement seal cartridge can be provided, and can be installed in the valve in replacement of the removed seal cartridge, thereby minimizing downtime of the valve.