Cocks

Marine cocks are used in auxiliary shipboard systems for local isolation, draining, venting, or basic flow control in water lines and other low-flow service circuits. Selection should be based on the service medium, operating pressure, installation location, frequency of operation, accessibility, and material compatibility with the marine environment.

This category covers brass marine cocks to JIS 16K, in type S and type U executions, in accordance with standards F7387 and F7388. These are straight-pattern manual valves intended for marine installations where a simple, mechanically robust shut-off arrangement is required.

Brass is typically specified for wet-duty and marine environments, subject to verification of suitability against the actual fluid composition, operating temperature, chloride concentration, and the risk of galvanic corrosion when connected to adjacent piping materials. The nominal JIS 16K pressure class must be matched against the actual design and operating conditions of the system. Interchange with other flange standards or connection patterns should not be made without dimensional and pressure-rating verification.

During installation, the direction of flow, full handle travel, shut-off tightness, sealing element condition, and access for periodic inspection should be checked. In drain, bleed, or sampling lines, allowance should be made for scale, salt deposits, or suspended solids that may affect seat tightness and smooth operation of the valve mechanism.