API Spec 6AV1 PDF

This standard identifies the design validation procedure requirements for a service class II or service class III API 6A surface safety valve (SSV), API 6A boarding shutdown valve (BSDV), or API 17D underwater safety valve (USV). Service class II is applicable to the validation of the valve bore sealing mechanism to seal performance in the presence of hard substances, such as sand. Service class III adds additional validation requirements for the performance in a similar environment of bonnet assembly sealing parts, including the stem seals.