API MPMS 2.2E:2004 pdf download

API MPMS 2.2E:2004 pdf download.Petroleum and Liquid Petroleum Products- Calibration of Horizontal Cylindrical Tanks Part 1: Manual Methods.
4 Precautions
4.1 General
The general and safety precautions given in Iso 7507.1 shall apply to this part of ISO 12917.
4.2 Internal method
Before a tank which has been used is entered, a sate-entry certificate, issued in accordance with local or national regulations, shall be obtained. All lines entenng the tank shall be disconnected and blanked. The national or local regulations regarding entry Into tanks which have contained leaded fuels shall be meticulously observed.
4.3 External method
National or local regulations regarding entry to the tank area shall be observed.
5 Equipment
5.1 Equipment as used In the ISO 7507 serIes
The equipment required to carry out the calibration is dependent on the method to be employed. This part of ISO 12917 uses techniques and equipment described in ISO 7507.1 Equipment used in the calibration of horizontal tanks shall conform with the specifications laid down in the relevant parts of ISO 7507, All equipment shall be traceable to a roferonce standard.
5.2 TelescopIc rod
5.2.1 In addition to the equipment mentioned in 5.1. a telescopic rod shall be used. This telescopic rod shall have a scale capable of being read to 1 mm. and shall be calibrated to within ± 0.5 mm.
5.2.2 The telescopic rod shall give a repeatability of maximum 1 mm
6 General requirements
6.1 The tank shall be filled to its normal working capacity and working pressure at least once and allowed to stand while full for at least 24 h prior to emptying and preparing the tank for calibration.
NOTE The hydrostatic test opçlied to new or repaired tanks will satisfy this requirement when additonal pressure tests are canted out.
6.2 The following variables shall be considered for the development of the capacity tables:
slopeftilt:
deadwood:
— temperature; pressure;
— liquid head:
— position of gauge point.
8.3 Repetition of measurements
After the circumference has been measured, the tension shall be released and the tape brought again to the
required level and tension. The readings shall then be repeated and recorded.
8.4 Tolerances
Measurements shall be read to the nearest 1 mm and shall be considered satisfactory if two consecutive readings are within ± 0.03 % of the circumference or 3 mm, whichever is greater.
If agreement is not obtained, further measurements shall be taken and recorded until two consecutive readings agree. The average of these two readings shall be taken as the circumference. If consecutive measurements do not agree, the reason for the disagreement shall be determined and the calibration procedure shall be repeated.
8.5 Other measurements on tank-shell plates
8.5.1 Plate and paint thickness
Plate. parit and any coating thickness shall either be measured for each course, whenever possible. by an ultrasonic device/primary method, or will be taken from the drawings. The plate and paint thickness for each course shall be recorded to the nearest 0.5 mm. Physical measurements are preferred to readings from drawings.
8.5.2 Length of the horizontal cylinder
The length of the horizontal tank (cylindrical part) shall be measured at the welding of the first knuckle at four measuring pornts representative of the length of the tank (see Figure 2).