Download - Watertightness Test Procedure
B 16-07-2013 Issued for client review
A 29-06-2013 Issued for combined review
Rev. Date Description Elaborated Revised Approved
CLIENT: CONTRACTOR:
Type of document:
PROCEDURE
Identification document: Rev. State:
Document title:
WATERTIGHTNESS TEST PROCEDURE
WATERTIGHTNESS TEST LEAF: 2 of 5
PROCEDURE EMISSION: 16/07/13
REVIEW: B
INDEX
1. Objective .................................................................................................................................. 3
2. Scope ....................................................................................................................................... 3
3. References ............................................................................................................................... 3
4. Definitions and Abbreviatures ............................................................................................... 3
5. Responsibilities ....................................................................................................................... 3
6. Procedure ................................................................................................................................ 4
7. Attached ................................................................................................................................... 5
WATERTIGHTNESS TEST LEAF: 3 of 5
PROCEDURE EMISSION: 16/07/13
REVIEW: B
1. OBJECTIVE
This procedure aims to describe the methods, requirements and parameters applicable for
the tightness test inspection for leak detection and airtightness checking and Settlement in
tanks manufactured for the project .
2. SCOPE
This procedure applies for the testing process tightness of atmospheric storage tanks of the
project .
3. REFERENCES
Manufacturing draws approved for the project.
API STANDARD 650 Eleventh Edition 2007 “Welded Steel Tanks for Oil Storage”
4. DEFINITIONS AND ABBREVIATURES
Atmospheric Storage Tank is a Container for a liquid which supports inside and outside
atmospheric pressure.
Tightness test pressure, pressure at the test is performed to verify their airtightness,
confirm its mechanical integrity and guarantee that they are in optimal operating condition.
The test is performed at atmospheric pressure.
5. RESPONSIBILITIES
Quality Inspector, responsible for the ongoing monitoring of the inspection, issuance the
inspection registration and report the finding of a defect to take the necessary corrective
actions without delay.
Manufacturing Supervisor, is responsible for ensuring that the tanks are available for
inspection by tightness test. It is also responsible for executing corrective actions as
determined by the Quality Inspector.
WATERTIGHTNESS TEST LEAF: 4 of 5
PROCEDURE EMISSION: 16/07/13
REVIEW: B
6. PROCEDURE
6.1. Tank Verification Before the Test
Verification of packaging, accessories poundage review and overall mechanical
completion verification.
It will be monitored that all requirements specified for non-destructive testing must be
completed and reported, visual inspection, liquid penetrant, vacuum test, pneumatic
test, radiographic tests.
Internal and external surfaces of the tank must be free of foreign elements that may
disturbed the inspection.
Welded joints must be free of paint, slag or any other foreign element that difficult the
leak detection.
Verify that nozzles and tank body accessories are covered ensuring that they have a
tight seal.
In the fixed-roof tanks, verify that roof manholes and nozzles are open and in the
same conditions during the test.
The tank should have no external piping connection except the filling pipe.
It will be located a common and permanent base measuring which it controls the
settlement.
For level settle measurements, it will be made marks on the bottom of tank,
considering the following: Measurements shall be performed with a maximum interval
of 3 meters measured diametrical lines around the tank. Diametrical lines are spaced
at equal angles, with a 10 m maximum of separation extent to tank circumference. We
will use minimum 4 diametrical lines.
6.2. Water catchment and Filling the Tank
Before dumping verify that the water used is clean.
Identify the location of the specific point where we will carry the dumping and uptake
of the water, time, volume and flow capture and dumping.
The temperature of the metal of the tank should not be lower than the design
temperature. The production supervisor is responsible for testing water heating if
necessary.
It will be held the tank to the height "H", maximum liquid level designed.
WATERTIGHTNESS TEST LEAF: 5 of 5
PROCEDURE EMISSION: 16/07/13
REVIEW: B
The minimum fill and minimum discharge rate, if it exist, will be:
Water Filling Rate
Bottom Course Thickness Tank Portion Maximum Filling
Less than 22 mm (7/8 in.) – Top course – Below top course
300 mm (12 in.)/hr 460 mm (18 in.)/hr
22 mm (7/8 in.) and thicker – Top third of tank – Middle third of tank – Bottom third of tank
230 mm (9 in.)/hr 300 (12 in.)/hr 460 (18 in.)/hr
6.3. Tightness Control
During filling, check the tightness of the tank, in the welded joints, as the elements
and component parts of the tank.
Readings will be taken as follows:
- Before starting the test.
- Upon reaching half filling level.
- Upon reaching the level of 3/4 filling.
- When you reach the maximum fill level.
- At least 24 hours after filling.
- After the tank has been emptied of water test.
When pores or cracks are detected, the tank should be empty up to a foot below the
localized failure, proceed to repair, and once finished the test is continued normally.
Finished the test, lower the water level during the time that the quality inspector
required to confirm the tightness.
Finished the inspection complete the form PTINC-CC-F-022 Registro de Inspección
por Prueba de Estanqueidad.
7. ATTACHED
7.1. Registro de Inspección por Prueba de Estanqueidad PTINC-CC-F-022