r- - ] t O PROCEDURES N i INSTALL ATION, OPERATION & MAINTENANCE BERTHOLD "M0LD LEVEL" GAUGE MODEL LB 300-2 ML FOR THE Q/B0P SLAB CASTING FACILITY STEEL PRODUCING DIVISION GARY WORKS GARY WORKS FEBRUARY, 1986 ' gogmotNo. 8 0 7 6 G = S' 2 n8s"e?!s0 13-07964-08 PDR i - | q -2- . BERTHOLD " MOLD LEVEL" GAUGE - SECTION I TYPE OF EQUIPMENT 1.1 GENERAL DESCRIPTION 1.1.1 The Berthold " Mold Level" Gauge is a highly sensitive 4 radiation measuring system consisting of a C0-60 source, which emits gamma rays contained within a heavy lead shielded container and included shutter mechanism. Attached to this system is a radiation scintillation detector, mounted on the opoosite side of the mold, which provides a signal used to control the flow of the liquid steel into the mold. 1.1.2 This device was manufactured by Berthold Systems, Ltd., West Germany. 1.1.3 This device is identified as follows: Mold Level Detection Gauge Model No. LB 300 ML Series 1.1.4 All drawings, relative to materials of construction, , assembly, source information and safety features, have been submitted, by the manufacture, to the Nuclear Regulatory Commission for their review and approval for use. The NRC Registration Number is as follows: NR-186-D-111-S. 1 i 1.2 APPLICATION 1.2.1 The Berthold " Mold Level" Gauge is capable of detecting the presence or absence of the molten steel within the mold and will be used to control the level of the molten steel with a high degree of accuracy and sensitivity. With this device, ( control is established on an " automatic" basis to preclude i dangerous conditions to exist, such as overflows or I breakouts, on the Q-B0P, No. 2, Continuous Slab Casting I ' Facility. 1.3 EQUIPMENT DESIGN ] 1.3.1 The Model LB 300-2 ML operates on the principle of gamma ray | absorption. The Cobalt-60, radioactive material source, emits gamma rays which are collimated by a shutter mechanism in the heavy duty, lead filled, source housing (see Berthold Assy. Dwy. No. 21260 000 000). The heavy duty shield is | mounted on a movable table tray connected to a " Carter" hydraulic system with a 28" stroke. This system permits ] access to the mold, when the source is in the closed position 3 and mold servicing is required. When the source is in the j use cr open position, the gamma rays are aligned with the ; scintillation detector through blind cavity ports on the f mold. When material is in the path of the radiation beam, less radiation reaches the detector than when material is absent. In this regard, the detector produces an output signal proportional to the amount of radiation detected. This signal is used to activate the caster pour control system. ____ . .. , . -3- 1.3 EQUIPMENT DESIGN (cont.) 1.3.2 The Model LB 300-2 ML level monitoring system uses a Cobalt-60, radioactive source containing a nominal 260 mci (250-300 mci) of Co-60 wire. The wire is taper coiled on a rod and encapsulated in an outer stainless steel capsule by Argon - Arc Walding. The outer source dimensions are approximately 11.4" x 1". The source drawings were previously submitted to the NRC by Berthold and found acceptable for this use under the Registration No. NR-186-D-111-S. 1.3.3 Each source head or housing acts as a complete storage container for the radioactive source subsequent to installation. 1.3.4 The gauge construction materials will not deteriorate from irradiation, corrosion, vibration, shock or other conditions that may exist at this facility. 1.3.5 C0nPONENTS PER SYSTEM 1.3.5.1 Model No. BL 300-2 ML (NRC) Reg. No. NR-186-D-111-S 1.3.5.2 Detector Assembly , 1.3.5.3 Electronic Modules 1.3.5.4 Indicating Lights (Red-Green) 1.3.5.5 Warning Signs - Symbols 1.3.6 The source housing assembly, which weighs approximately 2000 pounds each, is bolted to its individual table tray and cannot be moved following installation. 1.3.7 Each source head or housing contains an air actuated open and close shutter mechanism. 1.3.8 Each source head or housing contains a mechanical, spring type, closing mechanism for source safety control in the event electrical power or air control is lost. 1.3.9 Each source head or housing is equipped with both red and green warning lights that indicate shutter position; red for the open position and green for the closed position. Both lights are mounted in clear view and all concerned personnel instructed in their use. 1.3.10 Each source head or housing will be properly marked with the proper radiation sign and symbol and bear the manufacurer's label that shows the type of radioactive materials,'the amount, the date of manufacture, device model and other pertinent information. -4- - SECTION II INSTALLATION AND RELOCATION PROCEDURES 2.1 INSTALLATION 2.1.1 The word " installation" as used herein is defined specifically as the transfer of the Cobalt-60 source from the shielded shipping and storage containment system, as supplied by the manufacturer, Berthold Systems, Inc. into the Model BL 300-2 HL source head assembly (Berthold Dwy. No. 21260 000 000) previously installed at the molten metal mold face in the Q-80P - No. 2 Slab Casting Facility. 2.1.2 Installation of the specific Cobalt-60 source rod will be carried out by the manufacturer, Berthold Systems, Inc., 611 Park View Drive, Pittsburgh, PA, NRC License No. 37-21226-01, ) their specified and NRC approved representative or other persons specifically licensed to conduct this activity. 2.1.3 Delivery of the source will not be accepted at the Gary Works facility prior to NRC License approval for use. 2.1.4 Before delivery of the Cobalt-60 source rad, the Plant | Radiation Officer shall be contacted for instructions. 2.1.5 The shipping box or container shall be surveyed upon delivery and unloaded only if the radiation level conforms with 10 CFR 49 regulations and label markings. 2.1.6 The box shall be stored in a safe, locked and conspicuously posted location. 2.1.7 Upon removal of the outer cover of the shipping container, the manufacture representative will leak test the unit as well as inspect for damage and again survey for safety. 2.1.8 Prior to source installation, the manufacturer's representative i will inspect the Model No. LB 300-2 ML gauge shutter mechanism and provide assurance that the shutter mechanism is functional. 2.1.9 The manufacturer's representative shall make the initial ' radiation survey with the shutter lens in the open and closed positions, in accordance with an appropriate survey pattern sheet which shall be filed for permanent record. 2.2 RELOCATION 2.2.1 The word " relocation" as used herein is defined as the transfer of the entire nuclear device containing a sealed source, without altering or removing the source material, from the initial site, and placing it in a new position oi DONTROLNO. $0e706 $) storage. 2.2.2 Relocation for any purpose shall be conducted by the manufacturer or other persons specifically trained to conduct this activity. .. - - . _ - . -5- 2.3 LEAK TESTING 2.3.1 A leak test is defined as the conduct of a survey in such a manner that will provide evidence for the proof of the integrity of the source capsule. 2.3.2 Leak tests are generally made by wiping, the source or seams of the device or at those locations where, in the event of source leakage, contamination would most likely appear. 2.3.3 An initial wipe (leak) test shall be made after completion of the installation. 2.3.4 Wipe tests shall be made at least every six months thereafter. 2.3.5 Wipe tests shall be made after any relocation, and whenever damage to the device is suspected. 2.3.6 Following the initial leak test by the manufacturer, all subsequent leak tests shall be made by other individuals specifically licensed by the NRC. SECTION III OPERATING AND MAINTENANCE PROCEDURES 3.1 OPERATING PROCEDURES ' 3.1.1 Although radiation levels in the device areas are low, unescorted access shall be limited to authorized personnel who have received specific training in the operation of the equipment and informed of the existence and potential of radiation exposure. ; 3.1.2 All persons who will operate these devices or attendant equipment will have received specific training and instruc- ' tions regarding both the technical and radiation safety aspects. 3.1.3 Operation of these devices will be carried out in accordance with the instructions provided by the manufacturer-manual " Mold Level Detection Gauge, Section 10.6", Pages 10.6.10 through 10.6.30. j 3.1.4 Source assembly heads not in use shall be locked in their closed positon and be energized only under the direct supervision of the management personnel trained in radiation safety and operation of the device 3.1.5 The beam window in the shielding container may be opened only shortly before casting commences, or alternately for the i purpose of calibration of the system. It is closed again when the cast is complete. The beam window must also be closed, and remain closed, when any work is carried out inside the mold. | - _ _ . - - - - - _ - - . - -__ , -- . _ . _ - _ _ _ , | . : -6- . 3.2 MAINTENANCE PROCEDURES 3.2.1 Maintenance and repair of the device involving the opening of the device source housing or the removal of the sealed source shall not be performed by the licensee (U.