Duplex_Strainers_Q A.docx

Duplex Strainers:

Interested vendor questions/answers.

1 & 2) Do these valves require shock and vibration approval?

3.) Appendix C, D, E and F state that the new duplex strainers are to match up to existing piping. Can you send us the layouts of existing piping?

NAVSSES Responses:

1.) Shock and vibration testing or qualification will not be required for any duplex strainer or any sub-component, including valves, contained therein. Each duplex strainer will be installed in a land based test site at NAVSSES vice a US Navy shipboard system. COTS duplex strainers in accordance with ASME Section VIII, Div 1 requirements are acceptable.

2) Table 1 (Section 5.C) in Appendices C, D, and F specifies the following requirement: "Shutoff Valves/Equalizing Valves – Material and Type". NAVSSES will procure and install the shutoff (isolation valves) at the inlet and outlet flange for each duplex strainer as shown in the applicable facility system arrangement and detail drawing. These valves shall not be part of the procurement and the vendor should not provide these items. However, as required in their particular design, the vendor must provide equalization valves and changeover valves for switching between baskets and venting/draining the baskets in accordance with Table 1 requirements. Drain / vent valves shall also be required as listed in the valve specifications. These equalization / changeover valves shall be manual butterfly valves (or alternative ball valves) with gear operators and CRES 304 material (valve body). Remote operation / monitoring of these valves shall not be required, and hence, a "standard actuator with a 4-20ma input and position retransmit standard PID panel mounted RTD input with 4-20ma output reverse" shall not be required as specified in the vendor comment. Bronze valve materials shall also not be required as recommended in the vendor comment

3) The piping arrangement drawings of the applicable facility support systems cannot be released due to the sensitive nature of the program. The following nominal connection data from our CAD models for the inlet/outlet connections for each duplex strainer. Please see the enclosed file.