MANUAL OF PETROLEUM MEASUREMENT STANDARDS - EVAPORATIVE LOSS MEASUREMENT - WEIGHT LOSS TEST METHOD FOR THE MEASUREMENT OF RIM-SEAL LOSS FACTORS FOR INTERNAL FLOATING-ROOF TANKS
American Petroleum Institute
0 INTRODUCTION
1 SCOPE
2 NORMATIVE REFERENCES
2.1 API normative standards
2.2 ASTM normative standards
3 TERMINOLOGY
3.1 Definitions
3.2 Units of measurement
3.3 Nomenclature
4 SUMMARY OF TEST METHOD
5 SIGNIFICANCE AND USE
6 LIMITATIONS TO TEST METHOD
6.1 Evaluation of results
6.2 Low loss rates
7 TEST APPARATUS
7.1 Test apparatus schematic
7.2 Test room
7.3 Test assembly
7.4 Data acquisition room
8 TEST ITEM
8.1 Test item construction
8.2 Test rim seal attachment
8.3 Test rim seal end connections
9 PREPARATION OF APPARATUS
9.1 Test assembly placement
9.2 Test room air temperature control
9.3 Data acquisition room air temperature control
9.4 Steady state operation
10 INSTRUMENT AND CALIBRATION
10.1 Accuracy
10.2 Data acquisition system
10.3 Weight measurement
10.4 Temperature measurement
10.5 Voltage measurement
10.6 Atmospheric pressure measurement
11 TEST PROCEDURE
11.1 Rim-seal gaps
11.2 Data to be recorded
11.3 Duration of test
12 CALCULATION OF TEST RESULTS
12.1 Calibration corrections
12.2 Rim-seal loss rate
12.3 Vapor pressure function
12.4 Rim-seal loss factor
12.5 Uncertainty analysis
13 REPORT OF TEST RESULTS
13.1 Report
13.2 Loss rate curve
14 PRECISION AND BIAS
APPENDIX A LOSS RATE DETERMINATION
APPENDIX B UNCERTAINTY ANALYSIS
APPENDIX C METRIC UNITS
APPENDIX D BIBLIOGRAPHY
Figures
1 Plan view of a typical weight loss test facility
2 Elevation view of a typical weight loss test facility
3 Test assembly
4 Typical loss rate curve
A-1 Measured anc calculated weight loss versus time
A-2 Corrected and correlated weight loss versus time
Tables
1 Description of the symbols and units
2 Instrument requirements
A-1 Nomenclature for Appendix A
B-1 Nomenclature for Appendix B
B-2 Summary of example uncertainty analysis results
Used to establish evaporative rim-seal loss factors for rim seals for use on internal floating-roof tanks. The methods of test involve measuring the weight loss of a test assembly over time. It gives the test apparatus, the instruments, the test method and the calculation procedures to be used. The variables that are to be measured are defined, and quality provisions are stipulated. The format for reporting the values of both the test results and their associated uncertainty are also specified. This standard may involve hazardous materials , operations, and equipment.
| Document Type | Standard |
| Status | Current |
| Publisher | American Petroleum Institute |
| ProductNote | Reconfirmed 1998 |
