_RP_1102-2007_2017.pdf

Steel Pipelines Crossing Railroads and HighwaysAPI RECOMMENDED PRACTICE 1102SEVENTH EDITION,DECEMBER 2007REAFFIRMED,DECEMBER 2017ERRATA,NOVEMBER 2008ERRATA 2,MAY 2010ERRATA 3,SEPTEMBER 2012ERRATA 4,FEBRUARY 2014ERRATA 5,MARCH 2014Steel Pipelines Crossing Railroads and HighwaysDownstream SegmentAPI RECOMMENDED PRACTICE 1102SEVENTH EDITION,DECEMBER 2007REAFFIRMED,DECEMBER 2017ERRATA,NOVEMBER 2008ERRATA 2,MAY 2010ERRATA 3,SEPTEMBER 2012ERRATA 4,FEBRUARY 2014ERRATA 5,MARCH 2014Special NotesAPI publications necessarily address problems of a general nature.With respect to particular circumstances,local,state,and federal laws and regulations should be reviewed.Neither API nor any of APIs employees,subcontractors,consultants,committees,or other assignees make any warranty or representation,either express or implied,with respect to the accuracy,completeness,or usefulness of the information contained herein,or assume any liability or responsibility for any use,or the results of such use,of any information or process disclosed in this publication.Neither API nor any of APIs employees,subcontractors,consultants,or other assignees represent that use of this publication would not infringe upon privately owned rights.API publications may be used by anyone desiring to do so.Every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them;however,the Institute makes no representation,warranty,or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any authorities having jurisdiction with which this publication may conflict.API publications are published to facilitate the broad availability of proven,sound engineering and operating practices.These publications are not intended to obviate the need for applying sound engineering judgment regarding when and where these publications should be utilized.The formulation and publication of API publications is not intended in any way to inhibit anyone from using any other practices.Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standard is solely responsible for complying with all the applicable requirements of that standard.API does not represent,warrant,or guarantee that such products do in fact conform to the applicable API standard.All rights reserved.No part of this work may be reproduced,stored in a retrieval system,or transmitted by any means,electronic,mechanical,photocopying,recording,or otherwise,without prior written permission from the publisher.Contact the Publisher,API Publishing Services,1220 L Street,N.W.,Washington,D.C.20005.Copyright 2007 American Petroleum InstituteForewordThe need for an industry-recommended practice to address installation of pipeline crossings under railroads was first recognized by the publication of American Petroleum Institute(API)Code 26 in 1934.This code represented an understanding between the pipeline and railroad industries regarding the installation of the relatively small-diameter lines then prevalent.The rapid growth of pipeline systems after 1946 using large-diameter pipe led to the reevaluation and revision of API Code 26 to include pipeline design criteria.A series of changes were made between 1949 and 1952,culminating in the establishment in 1952 of Recommended Practice 1102.The scope of Recommended Practice 1102(1952)included crossings of highways in anticipation of the cost savings that would accrue to the use of thin-wall casings in conjunction with the pending construction of the Defense Interstate Highway System.Recommended Practice 1102(1968)incorporated the knowledge gained from known data on uncased carrier pipes and casing design and from the performance of uncased carrier pipes under dead and live loads,as well as under internal pressures.Extensive computer analysis was performed using Spanglers Iowa Formula 1 to determine the stress in uncased carrier pipes and the wall thickness of casing pipes in instances where cased pipes are required in an installation.The performance of carrier pipes in uncased crossings and casings installed since 1934,and operated in accordance with API Code 26 and Recommended Practice 1102,has been excellent.There is no known occurrence in the petroleum industry of a structural failure due to imposed earth and live loads on a carrier pipe or casing under a railroad or highway.Pipeline company reports to the U.S.Department of Transportation in compliance with 49 Code of Federal Regulations Part 195 corroborate this record.The excellent performance record of uncased carrier pipes and casings may in part be due to the design process used to determine the required wall thickness.Measurements of actual installed casings and carrier pipes using previous Recommended Practice 1102 design criteria demonstrate that the past design methods are conservative.In 1985,the Gas Research In