API RP 1133:2005(2010) pdf download

API RP 1133:2005(2010) pdf download.Guidelines for Onshore Hydrocarbon Pipelines Affecting High Consequence Floodplains.
• llectrn-hydraulic.
• Pneumatic.
• Mechanical (swing or drop check).
• Pilot operated.
There are three primary control modes &w valves:
a. Operated by local manual or local powered controls.
b. Rcnioic controls.
c. Automatic controls.
In a local manual control mode, the possibility of future remote operation of these valves should be considered when choosing the locations and types of block valves.
The control mode selected for operation of power-actuated valves should be coordinated with the overall hydraulic characteristics of the pipeline system. Important considerations include the topographic conditions along the pipeline and the proper sequencing of station shutdowns. In general, automatic. power-operated valves are not recommended on liquid pipelines without an appropriate surge analysis because pressure surges can occur in cases of sudden and/or uncornmanded closure. If the pipeline operator feels that an automatic valve is warranted, the pipeline operator should conduct a hydraulic analysis of the use of such valves. If automatic or remotely actuated valves are installed, the operator should provide protection against uncommanded closures and/or protection against excessive surge pressure.
4.4.3 Valve Design Considerations
Valve type. trim, and pressure rating should be compatible with service conditions of the pipeline and surrounding environment. All valves should he manufactured in accorckmce with API 6D Specifications.
In designing valve sites, consideration should be given to the installation of ficilities that would allow the Ilondplain crossing to be purged during emergency situations.
5 Construction
5.1 ENVIRONMENTAL CONSIDERATiONS
5.1.1 Permitting
Construction across many waterways requires government agency permits. For example, the U.S. Army Corps of Engineers. Environmental Protection Agency, and/or the U.S. Fish and Wildlife Agency may require permits as well as other fed- cml. state, and local agencies. Sufficient time should be allowed for obtaining permits and any required environmental studies. Local community involvement is encouraged to allow input about local concerns.the local environment. For example, open trenching across marshy. slow moving waterways may be acceptable. but it may he necessary to directionally drill or micrownnel under swift moving, environmentally-sensitive waterways. A process should be developed for handling slurry and cuttings froni the drilling process to prevent contanlination of the watercourse and surrounding areas. The following should be considered: composition of the slurry, temporary contain- ment. recycling and disposal.
Care should be taken not to endanger fish, cause environ- mental damage, increase stream turbidity or cause erosion during construction
5.1.3 Socioeconomic Impacts
Crossings of floodplains and waterways can take several weeks, or longer. to complcte Consideration should be given to the impact on the local population and users of ihe waterway or host bridge. If it is decided to construct 24 hours a day, steps should be taken to mitigate the impact on local residents and users.
5.2 SAFETY
5.2.1 Contingency Planning
Floodplain crossings provide some unique situations not commonly encountered during normal pipeline construction. in addition to the sidety considerations associated with the actual construction, forethought must be given to the waterway. adjacent work areas, and weather conditions. Contingency plans for rains, rising water, or flash floods should be considered, when appropriate.
5.2.2 Pumping Equipment
When the water flow is diverted by the use of cofferdams, flumes, or other techniques, these facilities must be designed to handle the highest expected water flows plus an acceptable contingency. If pumps or other mechanical equipment are used to move water around or out of the construction area. these pumps must be adequately sited to handle the range of flows expected. In addition, spare pumping equipment should be kep4 at the site in anticipation of mechanical failure of the primary equipment.