Information Notice No. NOTICE NO 83-31: Error in the Adlpipe Computer Program

                                                           SSINS No.:  6835 
                                                           IN 83-31        

                               UNITED STATES 
                           WASHINGTON, D.C. 20555 
                                May 19, 1983 

Information Notice No. NO 83-31:    ERROR IN THE ADLPIPE COMPUTER PROGRAM 


All nuclear power reactor facilities holding an operating license (OL) or 
construction permit (CP), nuclear steam system (NSS) suppliers, and 
architect-engineers (AEs). 


This information notice is provided as a notification of an error in the 
ADLPIPE computer program used for piping analyses. Although DIS/ADLPIPE, 
Inc. has informed their known users, all potential users of the ADLPIPE 
computer program may not have received the information. 

Description of Circumstances: 

A recent inspection of DIS/ADLPIPE, Inc. was conducted by NRC Region IV in 
response to a potential 10 CFR Part 21 report to Region IV by Burns and Roe,
Inc., that identified an error in the computer code ADLPIPE. The inspection 
disclosed that DIS/ADLPIPE, Inc. had notified only one user of the code, 
Burns and Roe. DIS/ADLPIPE verified that the error existed and provided a 
method of obtaining corrected data. During the inspection DIS/ADLPIPE, Inc. 
sent a letter of notification to the rest of the known users. 

According to the DIS/ADLPIPE, Inc. letter, the error involves the stress 
calculation at reduced outlet tee connections where the computer program 
option for the 1972 Winter Addenda to the ASME Code for Class 2 components 
is used. The error was introduced in the May 1974 version of ADLPIPE and was
contained in all subsequent versions. The DIS/ADLPIPE, Inc. letter stated 
that the error affects only calculations performed using the Class 2 
component option for the 1972 version of the ASME Code and does not affect 
calculations performed using the options for the 1974 and 1977 editions of 
the Code. Based upon this application, the error is not expected to affect 
reactor coolant system pressure boundary components. 

The error in the computer program involved the use of the run pipe section 
modulus for calculating stresses at the branch pipe termination. For the 
case of reduced outlet tee connections, this causes the stress to be 
underestimated at the branch side with the magnitude depending on the ratio 
of run pipe to branch pipe section modulus. 


                                                            IN 83-31      
                                                            May 19, 1983  
                                                            Page 2 of 2   

The error can be corrected by a simple hand calculation which multiplies the
computer program calculated moment stress at the branch pipe side by the 
ratio of the run pipe section modulus divided by the branch pipe section 
modulus. (The section modulus could be calculated in accordance with Section
NC-3652.4 of the 1972 Winter Addenda to Section III of the ASME Code.) 

It is suggested that holders of operating licenses or construction permits 
review this information for applicability to ASME Code piping analyses at 
their facilities. 

No written response to this notice is required. If you have any questions 
regarding this matter, please contact the Regional Administrator of the 
appropriate NRC Regional Office, or this office. 

                              Edward L. Jordan, Director 
                              Division of Emergency Preparedness 
                                and Engineering Response  
                              Office of Inspection and Enforcement 

Technical Contact:  J. R. Fair, IE 

List of Recently Issued IE Information Notices

Page Last Reviewed/Updated Friday, May 22, 2015