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- ARTICLE WB-
- WB-6100 General Requirements
- WB-6110 Pressure Testing of Components, Appurtenances, and Systems
- WB-6111 Scope of Pressure Testing
- WB-6112 Pneumatic Testing.
- WB-6112.1 Pneumatic Test Limitations
- WB-6112.2 Precautions to Be Employed in Pneumatic Testing
- WB-6113 Witnessing of Pressure Tests
- WB-6114 Time of Pressure Testing
- WB-6114.1 System Pressure Test
- WB-6114.2 Component and Appurtenance Pressure Test
- WB-6114.3 Material Pressure Test
- WB-6115 Machining After Pressure Test
- WB-6120 Preparation for Testing
- WB-6121 Exposure of Joints
- WB-6122 Addition of Temporary Supports.
- WB-6123 Restraint or Isolation of Expansion Joints
- WB-6124 Isolation of Equipment Not Subjected to Pressure Test
- WB-6125 Treatment of Flanged Joints Containing Blanks
- WB-6126 Precautions Against Test Medium Expansion.
- WB-6127 Check of Test Equipment Before Applying Pressure
- WB-6200 Hydrostatic Tests
- WB-6210 Hydrostatic Test Procedure.
- WB-6211 Venting During Fill Operation.
- WB-6212 Test Medium and Test Temperature.
- WB-6220 Hydrostatic Test Pressure Requirements
- WB-6221 Minimum Hydrostatic Test Pressure.
- WB-6222 Maximum Permissible Test Pressure
- WB-6223 Hydrostatic Test Pressure Holding Time.
- WB-6224 Examination for Leakage After Application of Pressure
- WB-6300 Pneumatic Tests
- WB-6310 Pneumatic Testing Procedures
- WB-6311 General Requirements
- WB-6312 Test Medium and Test Temperature.
- WB-6313 Procedure for Applying Pressure.
- WB-6320 Pneumatic Test Pressure Requirements
- WB-6321 Minimum Required Pneumatic Test Pressure
- WB-6322 Maximum Permissible Test Pressure
- WB-6323 Test Pressure Holding Time.
- WB-6324 Examination for Leakage After Application of Pressure
- WB-6400 Pressure Test Gages
- WB-6411 Types of Gages to Be Used and Their Location
- WB-6412 Range of Indicating Pressure Gages.
- WB-6413 Calibration of Pressure Test Gages
- WB-6600 Special Test Pressure Situations
- WB-6610 Components Designed for External Pressure
- WB-6620 Pressure Testing of Combination Units
- WB-6621 Pressure Chambers Designed to Operate Independently.
- WB-6622 Common Elements Designed for a Maximum Differential Pressure
WB-6114.2 1998 SECTION III — DIVISION 3 WB-
(3) the component is resubjected to the required system pressure test following the completion of repair and examination if the repair is required to be radio- graphed by WB-4453.4. (c) Valves require pressure testing prior to installation in a system in accordance with WB-3500. (d) Items which, when assembled, form a completed valve may be tested in the form of subassemblies, provided: (1) the test pressure is in accordance with the requirements of WB-6221; (2) the pressure test is performed in a manner which, in the subassembly under test, will simulate the loadings present when the completed pump or valve is assembled and pressurized; (3) the component Certificate Holder approves any pressure test of component subassemblies; (4) the component Certificate Holder specifies the pressure test requirements and test pressure to be used; (5) each subassembly pressure test is performed by a Certificate Holder and is performed in the presence of the Authorized Inspector; (6) each subassembly pressure tested by other than the component Certificate Holder is stamped with the NPT symbol, except as provided in WA-8330. The test pressure shall be identified on the Partial Data Report Form. (7) each subassembly pressure tested by other than the component Certificate Holder is listed on the Code Data Report Form; (8) the pressure tested subassemblies of pumps or valves are subsequently assembled by mechanical methods only; (9) welds examined during the subassembly pres- sure test need not be reexamined during the system pressure test.
WB-6114.3 Material Pressure Test. The component or appurtenance pressure test may be used in lieu of any such test required by the material specification for a part or material used in the component or appurtenance, provided: (a) nondestructive examinations, if required by the material specification, can be performed subsequent to the component or appurtenance pressure test; (b) the material can be repaired by welding in accord- ance with the rules of WB-4130, if required, as a result of the pressure test; (c) postweld heat treatment, when required after re- pairs, can be performed in accordance with WB-4620.
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WB-6115 Machining After Pressure Test An additional amount of material, not to exceed 10% of the wall thickness or 3 ⁄ 8 in. (10 mm), whichever is less, is permitted on the completed component during pressure testing where machining to critical dimensions and tolerances is required.
WB-6120 PREPARATION FOR TESTING
WB-6121 Exposure of Joints All joints, including welded joints, shall be left uninsulated and exposed for examination during the test.
WB-6122 Addition of Temporary Supports Components designed to contain vapor or gas may be provided with additional temporary supports, if necessary, to support the weight of the test liquid.
WB-6123 Restraint or Isolation of Expansion Joints Expansion joints shall be provided with temporary restraints, if required, for the additional pressure load under test.
WB-6124 Isolation of Equipment Not Subjected to Pressure Test Equipment that is not to be subjected to the pressure test shall be either disconnected from the component or system or isolated during the test by a blind flange or similar means. Valves may be used if the valves with their closures are suitable for the proposed test pressure.
WB-6125 Treatment of Flanged Joints Containing Blanks Flanged joints at which blanks are inserted to isolate other equipment during the test need not be retested.
WB-6126 Precautions Against Test Medium Expansion If a pressure test is to be maintained for a period of time and the test medium in the system is subject to thermal expansion, precautions shall be taken to avoid excessive pressure.
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WB-6127 WB-6000 — TESTING WB-
WB-6127 Check of Test Equipment Before Applying Pressure The test equipment shall be examined before pressure is applied to ensure that it is tight and that all low pressure filling lines and other items that should not be subjected to the test have been disconnected or isolated.
WB-6200 HYDROSTATIC TESTS
WB-6210 HYDROSTATIC TEST PROCEDURE
WB-6211 Venting During Fill Operation The component or system in which the test is to be conducted shall be vented during the filling operation to minimize air pocketing.
WB-6212 Test Medium and Test Temperature (a) Water or an alternative liquid, as permitted by the Design Specification, shall be used for the hydro- static test. (b) It is recommended that the test be made at a temperature that will minimize the possibility of brittle fracture (Appendix G). The test pressure shall not be applied until the component, appurtenance, or system and the pressurizing fluid are at approximately the same temperature.
WB-6220 HYDROSTATIC TEST PRESSURE
REQUIREMENTS
WB-6221 Minimum Hydrostatic Test Pressure (a) The installed system shall be hydrostatically tested at not less than either 1.5 times MNOP or 1. times MNIP of any component within the boundary protected by the overpressure protection devices which satisfy the requirements of WB-7000. (b) Valves shall be hydrostatically tested in accord- ance with the rules of WB-3500. (c) Components shall be hydrostatically tested at not less than either 1.5 times MNOP or 1.25 times MNIP.
WB-6222 Maximum Permissible Test Pressure The stress limits specified in WB-3226 shall be used in determining the maximum permissible test pressure. In multichamber components, pressure may be simulta- neously applied to the appropriate adjacent chamber to satisfy these stress limits.
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WB-6223 Hydrostatic Test Pressure Holding Time The hydrostatic test pressure shall be maintained a minimum of 10 min prior to initiation of the examination for leakage required by WB-6224.
WB-6224 Examination for Leakage After Application of Pressure Following the application of the hydrostatic test pressure for the required time (WB-6223), all joints, connections, and regions of high stress, such as regions around openings and thickness transition sections, shall be examined for leakage. Except in the case of valves which shall be examined while at test pressure, this examination shall be made at a pressure equal to the greater of the MNOP or three-fourths of the test pressure and it shall be witnessed by the Inspector. Leakage of temporary gaskets and seals, installed for the purpose of conducting the hydrostatic test and which will be replaced later, may be permitted unless the leakage exceeds the capacity to maintain system test pressure for the required amount of time. Other leaks, such as those from permanent seals, seats, and gasketed joints in components, may be permitted when specifically allowed by the Design Specification. Leakage from temporary seals or leakage permitted by the Design Specification shall be directed away from the surface of the component to avoid masking leaks from other joints.
WB-6300 PNEUMATIC TESTS
WB-6310 PNEUMATIC TESTING
PROCEDURES
WB-6311 General Requirements When a pneumatic test is performed, it shall be conducted in accordance with the requirements of WB- 6100 and this Subarticle.
WB-6312 Test Medium and Test Temperature (a) The gas used as the test medium shall be non- flammable. (b) Testing temperature shall be in accordance with WB-6212(b).
WB-6622 WB-6000 — TESTING WB-
WB-6622 Common Elements Designed for a Maximum Differential Pressure (a) When pressure chambers of combination units have their common elements designed for the maximum differential pressure that can occur during startup, opera- tion, and shutdown, and the differential pressure is less than the higher of the MNOP of the adjacent chambers, the common elements shall be subjected to a hydrostatic test pressure of at least 1^1 ⁄ 4 times the maximum differen- tial pressure. (b) Following the test of the common elements, as required by (a) above and their inspection, the adjacent chambers shall be hydrostatically tested (WB-6221). Care must be taken to limit the differential pressure between the chambers to the pressure used when testing the common elements.
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