PREVCO’s #4 dual seal vent plug is a modified SAE #4 plug, having an added face seal for increased reliability. The vent port is a standard SAE #4 design with one additional restriction; the spot face sealing surface needs to have a surface finish of at least 32 micro-inches. As most commonly machined ports meet this constraint, our No. 4 dual seal plug can be retrofitted to many existing designs which currently use a standard single seal port. Plugs are available in Stainless Steel (316), Titanium (grade 5), Monel K-500, Copper Beryllium and Inconel 625. Special Materials available upon request. PREVCO’s Leak Before Open Option provides a way for internal pressure begin to escape once the plug is backed out and is no longer sealed yet the threads remain engaged. This is important in cases where there's a concern about the plug becoming a projectile should there be internal pressure inside the underwater housing.

Technical Specifications

Features

• Leak Before Open allows internal pressure to reduce while plug threads remain engaged
• High reliability
• Recommended for higher volume designs
• Recommended to equalize internal pressure with ambient prior to endcap removal
• The interface can be used for vacuum leak checks
• 6000m operating depth

Components

• Inconel 625
• Viton O-rings as standard

Resources

• Interface Control Drawing
• STEP file
• Part number: 00669-006(LBO)