See close-up of Cam-Lock bolt
1. Cam-Lock Deck Covers
MMC deck covers for Butterworth openings are simply dropped into deck opening, then each of three helical cams is rotated one half turn to secure the unit to the deck. A self-contained, renewable O-ring gasket assures a pressure-tight seal. The overall result is a secure, oil- and water-tight closure. An MMC deck cover can be closed or opened in seconds without need for special tools.
Installation requires no drilling or doubler rings and no deck studs, nuts or gaskets. MMC Deck Covers are supplied in accordance with the ship's deck thickness. They are constructed of Navy-grade bronze with standard Buna-n seals. Other seal and cover materials are optional. Wider seal "L"-shaped gaskets are also available for use with unusually weathered deck opening surfaces.
2. Deck Covers for Vapor Valve Mounting
MMC also offers valve-mount deck covers that facilitate the installation of an MMC 2" flanged "B" vapor valve in an existing 12 1/2" diameter tanker deck opening. Constructed of bronze and stainless steel, the 4-cam valve-mount deck covers can easily be removed for tank mucking operations. They are available with a heavy O-ring or an "L" shaped deck seal.
The valve units can be used for cargo tank gauging, tank dryness checking and cargo sampling with closed or restricted sampling systems.
3. Centalock Deck Cover
MMC's Centalock deck cover fits flush to the deck surface and uses a convenient lift-and-turn handle to lock or loosen the plate. No tools are required for opening or closing. A sturdy three-prong spider-and-cam mechanism under the cover ensures a fast, tight fit. The high-strength bronze spider clamp assemply is actuated by a stainless steel acme threaded handle-clamping spider screw.
The cover unit is manufacturered of Navy-grade bronze with standard Buna-n seals. Other seal and cover materials are optional.