Interpretation Response #PI-73-038
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Dec 5 1973
Mr. Robert V. Warrick
Manufacturers Standardization Society of the Valve Fittings Industry
1815 North Fort Myer Drive
Arlington, VA 22209
Dear Mr. Warrick:
This is in response to your letter of October 26, 1973, and our conference on November 15 together with Messrs. Greenwald, Lattan, and George, representing the Manufacturers Standardization Society of the Valve and Fitting Industry regarding our interpretation of §192.149.
You indicate that the interpretation of §192.149 in our August 10, 1973, letter to Mr. R.W. Schneider has created considerable concern among manufacturers of these products and that you feel that the interpretation is in contradiction to that given to your office on November 9, 1970.
First of all, from the discussion in our conference regarding the last sentence of §192.149(b), we feel that the sentence should be clarified to properly interpret the need for testing of a prototype.
A clarification of that sentence, with parenthetical insertion added, would then read:
"...The actual bursting strength of the fitting must be at least equal the computed bursting strength of pipe of the designated material and wall thickness, as determined by as prototype that was tested to at least the (computed bursting) pressure required for the pipeline to which it is being added."
We stated in the letter to Mr. Schneider that "...in the case of bursting strength requirements for a particular fitting made in accordance with certain design specifications, size, material properties, and manufacturing process, such a new fitting would be tested to burst. After satisfactory test, any number of like fittings would be expected to meet strength requirements for such a type fitting" (underscoring added). This statement sets forth clearly the intent that any new type of fitting must have a prototype tested to burst. Any number of like fittings are then expected to meet similar strength requirements.
We then indicated in that letter that "If there is a change in size, material, design specifications, manufacturing process, or any other thing that could affect the performance, it would be expected that such a change would necessitate the testing of a new prototype."
The interpretation given to Mr. Schneider in our letter of August 10, 1973, was not in direct contradiction of the interpretation given to your office on November 9, 1970, but only clarified our understanding of the words "lines of fittings" used in your description of the specific practices in your letter of November 9, 1970, as meaning "like" fittings of the same design "specifications, size, material properties and manufacturing process."
If you feel that this testing of the prototype fittings should be modified, you may petition this Office to amend this rule. This petition should set forth the substance of the rule proposed, explain the interest of the petitioner, and contain information to support the action sought. Based upon the information you provide, we will evaluate this information and consider regulatory action in this matter.
We trust that this has clarified this matter. If we can be of further assistance, please let us know.
Office of Pipeline Safety