Metal bellows are used in globe valves to seal the plug stem to the atmosphere. The thin-walled corrugated cylinders are used as dynamic seals, particularly in applications where strict emission requirements apply. Metal bellows by SAMSON are made of corrosion-resistant materials. They are capable of withstanding high pressures and temperatures, which makes them ideally suited for use in high-performance service.
SAMSON's founding father, Mr. Hermann Sandvoss, had the metal bellows patented back in 1909. And valves fitted with metal bellows still continue to be the prime choice for challenging applications. This statement is backed up by the impressive sales figures: 20 % of all valves sold are equipped with metal bellows.
Modular design
Installation in Series 240, 250, 280, and 290 Valves (can also be retrofitted) as well as self-operated regulators
Product life cycle
The extra cost of fitting a valve with a metal bellows rather than a stuffing box packing to meet stricter emission requirements pays off: metal bellows are reliable, require no maintenance, and last long in service. When considering the entire product life cycle, metal bellows are the solution that offers the best cost-effectiveness.
Life cycle considerations
Quality and durability are the key features of metal bellows and make the investment worthwhile. As a result, SAMSON examined the durability of a metal bellows as part of the life cycle calculations. These calculations showed that the bellows can reliably perform 5,000,000 cycles.
At a glance
Metal bellows are primarily used to prevent external leakage. The metal bellows made by SAMSON comply with the emission limits specified in the following standards:
The EXPERTplus valve diagnostics integrated into the positioner provide reliable information on the condition of the metal bellows. The measured data are assessed based on a statistical analysis of the cycle heights that the valve moved through. The positioner issues a classified status message in compliance with NAMUR Recommendation NE 107 when a critical condition exists.
