Manifolds specified herein are intended for pressure reducing service in air or nitrogen systems where special acoustic requirements apply.

Selection of the manifold configuration will be in accordance with shipbuilding specifications. Configuration selection is based on the criticality of the application. The following serves as a guide for selection of manifold configuration:

(a) Configuration 1-1 (one reducing valve with a manual by-pass) should be selected for applications where, due to the infrequency and slow rate of load variations, the outlet pressure can be effectively regulated with a manual by-pass while the pressure regulating valve or filter is secured for maintenance or repair.

(b) Configuration 2-1 (two reducing valves in parallel) should be selected where it is mandatory to have an alternate source of automatically regulated pressure immediately available if one of the pressure regulators or filters is secured for maintenance or repair.

(c) Configuration SP (special configuration) is included to allow configurations required for special applications. For example, the inclusion of dual relief valve protection, of solenoid controlled loading for the regulators, or a manual by-pass meeting the same acoustic criteria as the automatic regulating valves.