API MPMS 3.1A:2005 pdf download
API MPMS 3.1A:2005 pdf download.Manual of Petroleum Measurement Standards Chapter 3- Tank Gauging Section 1A- -Standard Practice for the Manual Gauging of Petroleum and Petroleum Products.
Note: If the first two gauge readings are identical, that reading may be recorded without taking additional gauges, For statistical purposes, more than three readings may be taken and averaged ovcr.ill if preferred and mutually agreeable.
3.IA.11.1.1 Rolling Gauges
During lightering or ofFshore operations, or when the vessel is at an exposed berth, cargo may be moving during gauging. In such cases, at least live readings shall be obtained in minimal time, recorded. and then averaged. The outage gauges are to be taken as quickly as is practical and the immersion time of the bob/tape should be as brief as possible. It has been fbund useful to immerse the bob in the petroleum liquid and to lake readings from the tape. Adverse conditions such as these must be recorded.
3.IA.11.1.2 Closed Manual Systems
Closed Manual Systems refers to gauging equipment silnilar in array and construction to hand-held electronic gauging equipment, but not fitted with electronic sensing devices, which can be deployed in tanks with a closed or inert atmosphere.
3.IA.11.2 GAUGING VESSELS OUT OF TRIMILIST
3.IA.11.2.1 Gauging Procedure
Gauging procedures are not altered for vessels which are out of trim. In situations where both trim and list exist, every effort should be made to eliminate one or both conditions. On vessels where the reference gauge point is located at the center of the tank, trim will not significantly affect the gauge readings or the reference heights. Where the reference gauge points are located toward the after or forward ends of the tanks, trim correction must be applied to obtain the correct volumes. Apply the trim correction by using the trim corrections tables or instructions listed in the vcssel’s official Capacity Tables. If the necessary information is not listed in the Capacity Tables, refer o Appendix C.
Note: Origin of Capacity Thhkx. The origin of the capacity tables should be identified and recorded. It should be verified that the capacity tables refer to the actual ullage locations. For further information on calibration procedures, please refer to MPMS Chaprer 2.XH. Standard Practices for Calibration of Tanks on Ships and Ocean Going Barges.
b. The use of ullages. when the observed reference gauge height is less than the reference gauge height due to buildup of residue on tank bottom or due to structural members, cursature of tank walls. etc. (Alternate gauging locations should be checked to confirm presence of material throughout tank.)
3.IA.11.2.3.3 If no reference gauge height is indicated, it should be determined as follows:
a. When sounding depths are shown as well as ullages. use the ullagc reading corresponding to a zero sounding as the reference gauge height see Table I. rows Al and A2).
b. When sounding depths are shown to indicate the reference gauge height. the maximum ullage for which capacity is shown is considered to be the reference gauge height (see Table I, rows A3 and A4).
3.1A.11.2.3.4 In those cases where zero innagc is incasured and the reference gauge height is reached, the reported volume will be zero. Where significant volumes are shown below the reference gauge height. confirm readings if possible by measuring from another location capable of reaching deeper into the lank. When an innage is obtained, convert ii to an ullage.
3.IA.11.2.3.5 It is suggested that in case 5 (sec Table 1. row AS). extrapolate linearly down to the observed gauge height, using the barrclsiccntimcter of the pervious two tabulated values, in order to obtain a new volume, and then interpolate normally. ThLLS. if the table bottom is zero, ignore the discrepancy but report it in the documentation.
3.IA.11.3 OBQIROB MEASUREMENT
3.IA.11.3.1 Application
OBQ and ROB volumes can be determined by using either the innage or ullage method of gauging. While the techniques involved arc similar to those applied when obtaining a ullage or innage on partially full tanks, there are some significant differences when gauging ROB’OBQ.
