This specification covers direct reading boiler-water gauges including replacement glass sets.

Gauges shall be of the following types and classes, as specified (see 6.2.1):

     Type A - Continuous vision, plain, double, fiat glass.

          Class I   - For designed pressure to 700 pounds per square
                       inch gauge (lb/in2) (600 lb/in2 nominal) using
                       1500 lb/in2 glass.
          Class II  - For designed pressure to 1050 lb/in2 (900 lb/in2
                       nominal) using 1500 lb/in2 glass.
          Class IV  - For designed pressure to 2550 lb/in2 (2500 lb/in2
                       nominal) using 2500 lb/in2 glass.
     Type B - Reflex glass, pressures of 300 lb/in2 and under.

Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commander, Naval Sea Systems Command, SEA 55Z3, Department of the Navy, Washington, DC 20362-5101 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter.

For gauges and component gauge parts furnished under this specification, the complete gauges and replaceable component gauge parts shall be identified by part numbers in accordance with the following and as shown in table I: TABLE I. Part/assembly codes.

Code      Item                 Code         Item                
----------------------------------------------------------------
 00 Gauge, complete             60 Chain, sprocket, 40-foot     
 11 Glasses                     61 Sprocket wheel -  7 inch     
 12 Mica shields                62 Sprocket wheel -  8 inch     
 21 Glass positioners           63 Sprocket wheel -  9 inch     
 22 Spacers                     64 Sprocket wheel - 10 inch     
 23 Gaskets                     65 Sprocket wheel - 11 inch     
 24 Cover plates                66 Sprocket wheel - 12 inch     
 31 Frame body                  71 Hand wheel     -  7 inch     
 32 Clamping devices            72 Hand wheel     -  8 inch     
 41 Top connectors              73 Hand wheel     -  9 inch     
 42 Bottom connectors           74 Hand wheel     - 10 inch     
 51 Shutoff valves              75 Hand wheel     - 11 inch     
 52 Drain valves                76 Hand wheel     - 12 inch