API SPEC 12D:2008 pdf download

API SPEC 12D:2008 pdf download.Specification for Field Welded Tanks for Storage of Production Liquids.
if so agreed upon between the purchaser and the manulacturer, When flanged or other types of connections are specsfied, the nozzle neck shall be a minimum of standard weight pipe and attached by full fillet welds both inside and outside The bolting pattern for thief hatches shall conform to one of those shown in Figure 3. Thief hatches. when used, shoid be 8-in. x 22.in. obround for pressures up to and includIng 4 oz and 8-In, round for pressures greater than 4 oz. The purchaser shall provide full details of external piping loads or vibration excepted to be imposed on connections in the liquid section of the shell. The manufacturer shall provide additional reinforcement of these openings where required.
5.21 Dome
The dome shall be fabricated from ‘I in. material and shall be Installed as shown in FIgure 1. The cover shall be provided with an oil resistant gasket of !i in. minimum thickness,
5.22 Center Support
All tanks shall be provided with either a structural-type or a pole type center support, suitably attached to the rafter structure and to a beanng plate seal welded to the bottom. Where cone bottoms are fumeshed the center support shall not interfere with the function of the sump,
5.23 AntI-channel Drain Baffle
An anti-channel drain baffle conforming to the following requirements shall b€ furnished, if so specified on the purchase order.
a) The periphery of the baffle, in plan view, shall be 64 in.
b) The height of the baffle from the inside surface of the tank bottom to the top of the baffle shall be 5 1j4 in. minimum.
C) The baffle shall be equipped with the spacers so that the bottom edge of the baffle is I in. above the tank bottom.
d) A drain line shall be provided from the baffle to the tank shell. The line size shall be 4 in. nomiial.
e) The baffle shall be attached to the tank bottom by a J-bolt passing through an eye retainer welded to the tank bottom, and by the line connection to the tank shell. The baffle shall not be welded to the tank bottom.
5.24 Downcomer PIpe
A downcomer pipe shall be installed, if requested by the purchaser design of downcorner to be agreed between purchaser and manufacturer.
6 Venting Requirements
6.1 Normal Venting
Connection C-3 (see Figure 1) is provided for normal inbi’eathing and outbreathing due to temperature changes and to liqu movement into and out of the tank. This connection should be fitted with pressure-vacuum valve properly sized in accordance with API 2000. The pressure setting should be from 2 ozñn.2 to 4 ozhn.2 less than the operng pressure of devices used for emergency venting. Annex B is provided as a guide to aid in the selection of venting devices, where required.
The nameplate shall be stamped, etched or embossed on corrosion-resistant matenal and permanentty attached to a
bracket plate of ferrous material. Alternatively, 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 rnspector representing the purchaser shall have free entry, at all times while work on the contract of the purchaser Is being performed. to all paris of the manufacturers worIs which will concern the manufacture of the material ordered. The manufacturer shall afford, without charge, all reasonable facilities to satisfy the inspector that the materiM is being manufactured in accordance with this speciflcation 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 rriariufacturer’s operations.