Interpretation Response #02-0330 ([SMI Companies] [Michael W. Splane])
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: SMI Companies
Individual Name: Michael W. Splane
Location State: LA Country: US
View the Interpretation Document
Response text:
JUN 30, 2003
Mr. Michael W. Splane Ref. No.: 02-0330
Engineering Manager
SMI Companies
1456 Highway 317 South
Franklin, LA 70538
Dear Mr. Splane:
This responds to your December 10, 2002 follow-up letter regarding our November 22, 2002 response, from Mike Hilder, RSPA's Office of the Chief Counsel, to an earlier letter dated September 18, 2002, concerning technical compliance of an internal discharge valve design.
The November 22, 2002 letter responded to your request to further review information you provided previously (9/18/02) with respect to the portable tanks built by your company in 1997 for Aggreko LLC and approved by Commercial Union Insurance Companies. Based on our review, we found that the discharge valve on these portable tanks located within the "companion flange" is in technical compliance with § 178.270-12(c). However, in regard to location of the shear section, we stated the following:
There is insufficient information whether the shear section is located within 10.2 em (4 inches) of the tank vessel, as required by 49 C.F.R. § 178.270-12(d), when measured along the length of the discharge piping. We do not agree that the 4" requirement can be read to refer to empty space between the outside of the tank vessel and the discharge piping as shown in the sketches provided with your September 18 letter.
You do not agree with our finding regarding measuring the location of the shear section and asked how we arrived at determining that the length (10.2 em (4 inches)) must be measured along the length of the discharge piping. You also asked whether a "sandwiched shell" construction is permitted on 1M type vessels; if so would the "containment vessel" be considered part of, or at least an extension of the shell of the IM-l 02 portable tank.
The location of the shear section on the 1M 102 portable tank must be measured along the length of the discharge piping because the shell or head of the tank is best protected from the transfer of excessive moments when the entire shear section is within 4 inches of the shell or head, rather than when just the nearest point of the shear section is within that distance of the shell or head.
The term "sandwiched shell" relative to 1M portable tanks is not defined in the specifications in § 178.270 of the HMR. Provided the tanks meet the specification requirements of § 178.270, there are no prohibitions to your particular design of the 1M-I 02 portable tank, which is completely enclosed within a protective secondary containment vessel. The secondary containment vessel used to provide protection, however, is not considered part of, or extension of the shell of the IM-102 portable tank.
I hope this satisfies your inquiry
Sincerely yours,
Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards