API SPEC 12D:2008 pdf download
API SPEC 12D:2008 pdf download.Specification for Field Welded Tanks for Storage of Production Liquids.
NOTE 3 With &ainaqe as used in Tle C.1 • COlumnS means that fiaiiabIe or ombustible iquids will not be retained near the tank by clytes or firewalls.
7 Fabrication, Testing, and Painting
7.1 Fabrication
Fabrication shall be completed in the field in accordance with the applicable paragraphs of this specification, using the best modem practices When agreed upon between the purchaser and the manufacturer, tanks may be completely fabricated in the manufacturer’s shop pnorto delivery to field location.
7.2 Welding
Welding procedures shall be established and wekhng operators qualified by the manufacturer. Qualification of welders m accordance with the applicable parts of the latest edition of Section IX of the ASME Boiler’ and Pssure Vessel Code is recommended.
7.3 Testing
Bottoms of field erected tanks shall be tested by applying vacuum to the pints. and using soap suds, linseed oil. or other suitable matonal tar the detection of leaks. The completed tank shall be tested by fteWg with water for a penod at not less than 12 hours, and testing the deck either by applying air pressure or by vacuum testing the joints Test water shall be provided and removed by the purchaser, unless otherwise agreed upon. Alternatively, if so agreed upon between the purchaser and the manufacturer, the tank may be tested with air pressure at 1 112 times the design pressure of the tank (see 5.1 and 5.17).
Caution: When testing air, adequate valves, regulators, and pressure relief devices shall be used to prevent overpressure or permanent deformation.
Testing and the repair of any defects shall be completed before connecting any piping to the tank.
NOTE Vacuum testing may be conveniently performed by means of a testing box. 6 Wi. x 30 in.. wth a glass window in the top, the open bottom being sealed agarist the lank surface by a sponge rubber gasket Sutable connections, valves, and gauges roust be provided About 30 r, of the seam under test should be brushed with a soap-suds sokjtion or linseed oil. In freezing weather, a non-free2Fg solution may be necessary, Place the vacuum box over the coasted section at seam, and apply a vacuum to the box. The gauge should register a partial vacuum of at least 2 lMn.2. Porosity in the seam is indicated by bubbles or foam produced by air sucked drough the welded seam, A vacuum can be drawn on the box by any convenient method, such as connection to a gasoline or diesel motor intate manifold, or to an air ejector or special vacuLsTi pump.
7.4 External Painting
Alter erection, tanks shall be cleaned of rust, grease, scale and weld spaller Preparation for coating and the application of primer or finish coatings shall be by agreement between the purchaser and the manufacturer.
7.5 Internal Coating
Where internal coating is required, procedures and methods outlined in NACE RP 0372 are recommended, as a minimum requirement Other coatings and methods may be used by agreement between purchaser and manufacturer.
7.6 Cleaning Up
Upon completion of erection, the manufacturer or erector shall remove or dispose of all rubbish and o4her unsightly material caused by erecting operations and shall leave the premise in as good condition, as found.
The nameplate shall be stamped, etched or embossed on corrosion-resistant material and permanently attached to a
bracket plate of ferrous material. Altermnatively, nameplate information may be die stamped on a steel plate. The
bracket, backing plate or nameplate shall be seal-welded to the tank shell in the location shown in Figure 1.
9 Inspection and Rejection
9.1 Inspection Notice
Where the inspector representing the purchaser desires to inspect tanks purchased or witness any specified tests, reasonable notice shall be given of the time at which such inspection should be made.
9.2 Inspection by Purchaser
The inspector representing the purchaser shall have free entry, at all times while work on the contract of the purchaser is being performed, to all parts of the manufacturer’s works which will concern the manufacture of the material ordered. The manufacturer shall afford, without charge, all reasonable facilities to satisfy the inspector that
the material is being manufactured in accordance with this specification. All inspections should be made at the place of manufacture prior to shipment, unless otherwise specified on the purchase order; and shall be so conducted as not to interfere unnecessarily with the manufacturer s operations.
