Duplex_Strainers_Appendix_C_-_Spec_8035_0002.docx

NAVSSES Closed Loop Cooling Water Duplex Strainer Technical Specification Appendix C – UID 8035_0002 Date: June 2015

June 2015

Table of Contents

List of Tables

Scope of this Specification A. This specification provides the technical requirements for the design, performance, construction, inspection, testing, and warranty of three (3) duplex strainers to support a facility closed loop cooling water system.

B. This specification is broken down into the following sections:

1. Scope of this Specification

2. Equipment Overview

3. Applicable Codes, Standards, and Regulations

4. Rating, Conditions of Service, and Performance Warranty

5. Performance Requirements

6. Inspections and Tests C. Throughout this specification the following terms apply:

1. “Seller” refers to the Original Equipment Manufacturer (OEM) / Equipment Provider.

2. “Buyer” refers to NAVSSES (Naval Ship Systems Engineering Station).

3. “Manufacturer” refers to the party or parties that manufacture a part or parts of the equipment or material.

Equipment Overview A. The duplex strainers will all be installed and operated indoors on the Government provided site at NAVSSES (Philadelphia, PA). The duplex strainers will be installed in a facility closed loop cooling water system. To mitigate any potential contamination of the system end users, a suitably sized full-flow duplex strainer will be installed downstream of the system plate heat exchanger and upstream of each supply branch main header to the associated end users.

Applicable Codes, Standards, and Regulations A. The equipment shall be in compliance with the latest applicable regulations of applicable industry standards such as the American Society of Mechanical Engineers (ASME), American Society for Testing and Materials (ASTM), and the American Welding Society (AWS).

B. ASME Standards

ASME Section VIII, Div 1, Design and Fabrication of Pressure Vessels ASME B16.5, Pipe Flanges and Flanged Fittings ASME B40.1, Accuracy for Pressure Indicating Dial Type, Elastic Element Gauges

C. ASTM Standards

ASTM A182, Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service ASTM A312, Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes ASTM A403, Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings

D. AWS Codes

AWS D1.1, Structural Welding Code - Steel Rating, Conditions of Service, and Performance Warranty Equipment Ratings, Materials, and Workmanship A. The equipment provided shall meet the performance data provided in Section 5 of this specification.

B. Materials used for work performed under this contract shall be new, of the highest quality, and suitable for the intended service conditions of the equipment.

C. Work shall be performed by skilled mechanics in the various crafts and be executed in a first class and workmanlike manner in accordance with recognized good practice in the industry.

Conditions of Service A. The equipment will be located indoors in a non-climate controlled space and shall be designed for, and be protected against, these prevailing conditions as well as those identified in this specification. The duplex strainers shall function at any continuous environmental temperature from 40° F to 122° F.

Acceptance, Performance Warranty and Defects Liability A. Acceptance of the equipment by the Buyer shall follow the successful completion of all tests identified in Section 6 of this specification, including the review and approval of all Seller test reports by the Buyer upon successful completion of all tests.

B. The Seller shall warrant that the equipment supplied shall be entirely suitable for the intended service and is free from faults in design, and is of sufficient capability to meet the specified performance requirements (Section 5).

C. The Seller shall warrant the equipment for a period of at least twelve (12) months from the date of delivery. This shall warrant all equipment furnished by the Seller against defects in design, material, and workmanship.

Performance Requirements A. General Construction:

· The strainers shall be of the duplex basket type with valves and constructed to be readily opened for examination, removal, and cleaning of the baskets. The strainers shall be provided with shifting means to permit changeover (the act of shifting flow from strainer basket to the other) without damage to any parts or disruption of normal system operation for basket removal / cleaning. The strainer compartments shall each have a set of vent and drain valves. A changeover mechanism and an equalizing feature shall be included in the design for each strainer. Flow through the basket shall be “inside-out”.

B. Safety Interlocks:

· Positive interlocks shall be provided to prevent the following operator actions:

· Changeover to an off-duty compartment when the off-duty compartment cover is off or when the drain and equalizing valves are open

· Remove or loosen the cover when the compartment is pressurized

· Open the drain valve on the compartment in service

C. The following technical requirements shall be satisfied by the provided duplex strainers:

Table 1: Duplex Strainer Technical Requirements

Normal System Flow Rate

Stainless steel 304 ball valves (full port) for the changeover valves may also be used as an alternative. The use of two 3-port ball valves in place of inlet and outlet valves for each side of the strainer may also be included as an alternative design. The equalizing valve shall be separately operated from the changeover valve so that the offline basket can be filled / vented prior to any opening of the inlet or outlet port for the offline basket.

Stainless Steel 304 Butterfly Valves, Single Gear Operator Stainless steel 304 ball valves (full port) for the changeover valves may also be used as an alternative. The use of two 3-port ball valves in place of inlet and outlet valves for each side of the strainer may also be included as an alternative design. The equalizing valve shall be separately operated from the changeover valve so that the offline basket can be filled / vented prior to any opening of the inlet or outlet port for the offline basket.

Ensure compatibility with system materials.

If drain valves (not required) are also provided by the Seller, drain valves shall be 3/4” ball valves with a hose connection and cap.

2” NPT drain connections (qty 2) located at basket housing bottom to fully drain strainer If drain valves (not required) are also provided by the Seller, drain valves shall be 2” ball valves with a hose connection and cap.

Required to drain strainer.

If vent valves (not required) are also provided by the Seller, vent valves shall be ½” ball valves with a hose connection and cap.

½” NPT vent connections (qty 2) located on basket covers to fully vent strainer If vent valves (not required) are also provided by the Seller, vent valves shall be ½” ball valves with a hose connection and cap.

Required to vent strainer.

If supplied, each DP gauge shall be as follows: 0-10 psid range, 2 psi figure intervals, 0.25 or 0.5 psi smallest gradation, +/- 1.0% accuracy of span, gauge shall be red-lined per DP (max) at normal system flow (clean); required gauge connections, tubing, and valves shall be provided by the Seller; all DP gauges shall be tested and calibrated in accordance with the requirements of ASME B40.1 Class 1A.

DP Gauge, gauge connections, and valves (if available) If supplied, each DP gauge shall be as follows: 0-10 psid range, 2 psi figure intervals, 0.25 or 0.5 psi smallest gradation, +/- 1.0% accuracy of span, gauge shall be red-lined per DP (max) at normal system flow (clean); required gauge connections, tubing, and valves shall be provided by the Seller; all DP gauges shall be tested and calibrated in accordance with the requirements of ASME B40.1 Class 1A.

DP Gauge will facilitate local monitoring of the DP across strainer and initiate cleaning process if required.

If supplied, each DP switch shall be as follows: 0-10 psid range, stainless steel wetted materials and pressure connections, watertight enclosure, adjustable setpoint, SPDT or 2 SPDT contacts DP Switch and switch connections (if available) If supplied, each DP switch shall be as follows: 0-10 psid range, stainless steel wetted materials and pressure connections, watertight enclosure, adjustable setpoint, SPDT or 2 SPDT DP switch will facilitate remote monitoring with alarm of the DP across strainer and initiate cleaning process if required.

Inspections and Tests A. Final inspection and testing of the equipment shall be performed by the Seller or Manufacturer as follows:

Table 2: Required Equipment Inspections and Tests

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