This type of sealing is made using a 98 Sh hardening elastomer with circular or delta section.
This configuration can be added to an insert that performs the function of a scraper (configuration recommended for fully welded valves).
The advantage of this seal is that it can be coupled to non-lapped balls while losing effectiveness with increasing and decreasing temperature and increasing pressure.
Delta with metal ring and thermoplastic insert
![Delta-con-anellino-metallico-e-inserto-termoplastico](https://bbdsrl.it/wp-content/uploads/2018/01/Delta-con-anellino-metallico-e-inserto-termoplastico-1.jpg)
Delta with thermoplastic insert
![Delta-con-inserto-termoplastico](https://bbdsrl.it/wp-content/uploads/2018/01/Delta-con-inserto-termoplastico-1.jpg)
Delta with metal ring
![Delta-con-anellino-metallico](https://bbdsrl.it/wp-content/uploads/2018/01/Delta-con-anellino-metallico-1.jpg)
O-Ring
![O-Ring-Analisi-tenuta](https://bbdsrl.it/wp-content/uploads/2018/01/O-Ring-Analisi-tenuta.jpg)