Charles Wheatley Company — Pipeline Safety Interpretation

Page 171-00-00 Mr. Del Moore, Chief Engineer Charles Wheatley Company 911 South Main Street Tulsa, Oklahoma 74119 Dear Mr. Moore: This refers to your letter of June 7, 1971 and our reply of June 18, 1971, concerning certain aspects of the liquid pipeline regulations, particularly Section 195.426. The main purpose of Section 195.426 is to minimize the opening of end closures on scraper and sphere facilities while the facility is subjected to pressure, and thereby reducing the possibility of injury to personnel removing the end closure. There are two requirements contained in Section 195.426. One requirement is that the barrel in which the scraper or sphere is inserted or removed contains a relief device, such as a blowoff, which can be used to relieve pressure on the barrel prior to opening the end closure on the barrel. The second requirement is that the end closure itself must contain a device to either prevent the closure from being removed prior to release of the pressure on the barrel or to indicate that pressure still remains on the barrel. The "lock and bleed" device on Yale closures and the "pressure warning device" on Tube Turn closures satisfy the second requirement mentioned above. You raised the question in your June 7, 1971 letter, as to whether the above mentioned devices would satisfy the "relief valve feature" of the regulation. Section 195.426 contains the term "relief device" but not the term "relief valve." You might have been thinking of a device that would relieve pressure in the barrel automatically if it become as high as the preset valve on the relief valve. Section 195.426 contains no such requirement. The information that you recently provided to this department, revealed that the scraper and sphere facilities designed by your firm include a blowoff device, as previously mentioned, in addition to the "lock and bleed" device. This indicates that the Charles Wheatley Company is fulfilling the requirements of Section 195.426 in design of scraper and sphere equipment. Sincerely yours, Mac E. Rogers Director Bureau of Railroad Safety DB/dal/195.426 71-00-00 1#