Richard Blauvelt Don Krause Keith Rule Harold Shoemaker WPI B&W Services Inc. PPPL DOE/FETC

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1 DEMONSTRATION OF A LIGHTWEIGHT PORTABLE CRIMPER YIELDING GASTIGHT SEALS FOR THE EFFICIENT REMOVAL OF TRITIUM CONTAMINATED TUBING AND PIPE ON THE MOUND D&D LARGE SCALE DEMONSTRATION AND DEPLOYMENT PROJECT Richard Blauvelt Don Krause Keith Rule Harold Shoemaker WPI B&W Services Inc. PPPL DOE/FETC ABSTRACT The Mound Plant in Miamisburg Ohio was constructed just after WW II to continue its role in the development and production of nuclear weapons that began as part of the Manhattan Project in several separate laboratories in Dayton. From 1947 until the end of the Cold War, Mound played a key role in the production of both nuclear and non-nuclear components of the U.S. nuclear weapons arsenal. With the cessation of nuclear weapons production, Mound has been designated as a site to be closed and turned over to the local community for possible commercial reindustrialization. The shutdown involves a massive D&D effort of Mound s nuclear facilities, some of which are being demolished while others are cleaned up to industrial or free release standards. The major D&D project is focussed on the tritium processing facilities at Mound with the R/SW Building complex slated for demolition and the T Building scheduled for clean up to free release. A significant portion of this work involves the removal of gloveboxes, vacuum and transfer pumps, tanks and other pieces of process equipment contaminated with tritium and tritium compounds. Connecting all of this equipment are literally miles of stainless steel and copper tubing ranging from capillary tubing utilized for sampling and analysis to larger double walled (tube within a tube) transfer lines which were used to move large quantities of tritium from lab to lab and between process buildings. The removal of this tubing safely and efficiently represents a daunting challenge for the B&W Team responsible for the D&D of these tritium facilities, a project that is on the critical path for closure of the Mound Plant. The potential for release of tritium during these operations requires that extreme care be exercised, as the allowable release goals are relatively small. The baseline approach to this problem involves a series of steps including; 1. Purging the line to remove contamination to the extent possible with the purge gas going to a tritium effluent removal facility (TERF) 2. Constructing a sweep enclosure at the point of the tubing cut to ensure any release of tritium is captured. 3. Cutting the tube with traditional techniques such as saws, tubing or bolt cutters. 4. Capping the ends of the tubes immediately afterward. This innovative technology demonstration involves the use of a portable relatively lightweight hydraulically powered crimper that delivers 10,000psi and applies 12 tons of force to the crimping area. In addition, a specially modified die focuses that force and provides a pattern of indentations in the tubing that enhances the seal and facilitates the final cut. The result is a gastight seal that ensures containment of any residual tritium contamination and removes the necessity for any containment around the cutting area. The final cut can then be made with a tool from baseline tool kit, preferable a bolt cutter that generates little or no secondary waste as opposed to a saw or tubing cutter. While there are numerous crimping tools available commercially, this particular unit is unique in the ability to provide the leaktight seal that is so critically important to the safe removal of tritium contaminated tubing. This paper will provide details regarding the search for a suitable base tool and the redesign of the dies. It will also describe the cold testing that was conducted on a variety of tubing configurations. In addition, information will be presented that compares the performance and cost of this technology to the baseline approach. Demonstration data will be collected on actual contaminated tubing removal in the SW Building and recommendations will be presented concerning the deployment of this technology at the Mound site and other applicable D&D sites.

2 INTRODUCTION The Mound Facility is an ideal candidate for a D&D Focus Area Large Scale Demonstration and Deployment Project since its closure requires the D&D of numerous radioactively contaminated facilities. The tritium operations areas in T Bldg. and the SW/R Bldg. complex are on the critical path for the closure project. This means that the deployment of innovative technologies into this baseline project is not only an attractive idea but something that may be required if the projected cost and scheduled are to be met. A number of innovative technology candidates have been identified for potential demonstration in the Mound project ranging from characterization techniques to decontamination and dismantlement methods to preparation of waste for disposal. The specific technology being evaluated in this demonstration is commercially available hydraulically powered pipe crimper that has been modified to exert 12 tons of crimping force on a small surface area of a tube or pipe. The crimping head itself is relatively lightweight at approximately 8 lbs. with a remote power unit that can be moved around easily. The dies for the head have been modified by PPPL personnel to focus the crimping force and provide a pattern of creases in the tubing that results in a leak tight seal even when the contaminated tube is surrounded by another tube for containment. The potential for crimping and subsequently cutting the tubing without the need for some type of protective enclosure of the tubing or the necessity for placing the workers in air supplied suits are the primary potential benefits for this technology demo. Removal and disposal of several thousand feet of tritium-contaminated stainless steel capillary and single and double jacketed tubing is a significant and time consuming part of the decontamination and decommissioning of the Mound Tritium Facilities. The capillary tubing typically consists of 1/8 OD stainless steel tubing some of which is inside of a 3/8 OD stainless steel tubing that provides secondary containment. The capillary tubing was primarily used for sampling where small hold-up volumes were desirable. Other transfer lines are larger in diameter and also double jacketed. An example of some of the tubing is shown in figure 1. Figure 1-Capillary tubing requiring crimping and removal

3 In order to remove this tubing, it must be safely cut (and sealed) into lengths that are suitable for packaging into waste containers for disposal as low level radioactive waste. Currently, the tubing is cut using various manual cutting tools (i.e. hacksaw, sawzall cutting torch, tubing cutter, etc.). This paper summarizes the demonstration of a hand-held, remotely powered crimper for removing the tritium-containing capillary and transfer tubing. Burndy Electric, a division of Framatome Connectors, USA, offers a hand-held crimping unit capable of producing 10,000 psi of hydraulic pressure with a resulting force of 12 tons. This unit may prove to be a safer, more cost-effective method for the removal of contaminated tubing. This crimper is intended for use in conjunction with a shearing tool such as a bolt cutter to isolate and remove tubing. It is expected that, upon completion of the tests set forth in this paper, the remote-powered pipe crimper will be incorporated into a new procedure for tubing removal. In addition to its mobility, the primary advantage of this technology when applied to tritium D&D is that this unit creates a leak-tight crimp. It is expected that tritium emissions from the tubing removal operation will be substantially reduced or could be eliminated altogether. The expected advantages of this technology include; 1. A portable lightweight small crimping head that will enhance worker comfort, safety and productivity. 2. A transportable power unit with a 25 ft. hose that combined with the head allows crimping in confined or high bay areas. 3. A specially fabricated die incorporating a pair of embedded stainless steel dowel pins that concentrate the crimping force over a small surface area, providing a leak tight seal. 4. A reduction in airborne emissions for the total D&D project The unit is pictured in figure 2 Figure 2-the AC powered Burndy crimper A series of tests are being run to show that this innovative technology provides a significant advantage to other techniques for a variety of single and double walled tubing and pipe up to 1 inch in diameter. This advantage is the result primarily of the leaktight seal that the crimper provides to the tube. The baseline approach requires that a vacuum be pulled on one end of the tube being cut and a cap or other type of seal be placed on the end of the tube immediately after cutting. Because there is a potential for off gassing, radiological controls usually require that an enclosure be constructed around the cut to allow any venting to

4 be captured. The crimper will negate the need such an enclosure, with a tremendous saving in time and materials The full scale demonstration is being conducted in SW Building, room 2. This is the location of a former mass spectrometer facility used in conjunction with tritium operations. It contains all of the types of tubing that the project is interested in including in the demo. Phase I of the demonstration included a number of crimps on an variety of tubing types and was a cold test that could be performed in a designated area adjacent to SW Building. Phase I provided training for pipe fitters in the use of the crimper and also verified the ability of the crimper to make a leak tight seal with the types of tubing, both single and double walled that will be encountered in SW2. The demonstration with contaminated tubing will involve crimping a fixed number of linear feet of tube with both the Burndy crimper and the baseline approach, with attention given to the similarity of the scenarios such as the number of interferences or other complications encountered in real work. As part of the full scale demo certain prerequisites were necessary such as; all demo participants in a pre-job briefing must review and sign the applicable Radiological Work Permit (RWP). A pre-job conference must be scheduled with the RCT to accomplish this task any discuss. The demonstration data collector/test engineer will ensure that all necessary forms for collecting data will be available before, during, and after the demonstration including forms specific to the demo and forms common to both processes. All those participating in the demonstration will be familiar with the facility s operational procedures, and proper responses to alarms and emergencies. TECHNICAL APPROACH Prior to the demonstration, shakedown tests were run with a sampling of the types of tubing and pipe of interest to dampen the learning curve for the use of the crimper. This is in addition to and a precursor the Phase I work described above. It provided a familiarity with the basic operation and maintenance of the equipment and identified any problems or limitations before beginning the actual demonstration phase: The demonstration is being conducted in two phases. Each phase will provide data that will be relevant to either the performance of the crimper or the operating cost per linear foot of tubing crimped or treated with the baseline approaches. Phase I Phase I activities took place adjacent to SW building and measured the performance of the Burndy crimper for the crimping and leak-tight sealing of a variety of tubing from ¼ inch to 1 inch. Each tube sample was sealed on one end and placed in a fixture that enabled a vacuum to be placed on the tubing interior. The tubes were then crimped in a one crimp and three-crimp pattern (separate tests). The crimps were cut with a bolt cutter and the leak tightness of the crimped tubing was measured with a vacuum gauge, looking for a rate of rise. In addition to several examples of single walled tubing, both copper and stainless steel, the two double-walled transfer tubing configurations utilized at Mound were also tested. Furthermore, a test was conducted that demonstrated the performance of a crimp on tubing containing water and tubing containing oil. The results of phase I were somewhat obscured by a design flaw in the test fixture which did not allow for isolation of each test tube from the rest of the system. However, sufficient data was collected to justify the scheduling of phase II. Furthermore, this cold work allowed the workers to notice that there was some movement in the jaws at the outside edge of the die that resulted in an uneven distribution of the force on the tube surface. To compensate for this motion, the dowels in the die were raised at the open end by.015. The crimping head with the raised dowels can be seen in figure 3.

5 Figure 3-the crimping head Phase II Phase II activities will involve side by side comparisons of the crimp and cut approach with the baseline technology of using cutters or saws with the primary focus on labor data and airborne tritium monitoring. An equal number of feet for each type of tubing/piping will be identified and tagged. The plan would call for a minimum five crimp/cuts to be made for each type/size of tubing. Standard operating procedures for the baseline and the crimp/cut will be followed as called out in the work instructions for SW2 piping removal. Data from phase I may be used to petition for relief from any requirements for local air sweeping during the cut. In addition to the collection of labor data, each cut will be closely monitored for any tritium release. Preliminary phase II work has been completed on both single and double walled tubing in SW2. Each section of tubing was between 20-25ft. in length and had been under a slow purge with air to an effluent removal system prior to the crimp and cut. A sensitive portable tritium monitor was used to sniff the area adjacent to the cut to detect any release. There was none. An example of the crimp is depicted in figure 4.

6 Figure 4-examples of the crimped surface of a single wall 3/8 OD tube CONCLUSIONS Although additional hot testing remains to be done, the initial results with the crimper have been very promising. This technology has been well accepted by the workers in the field. In fact, they quickly improved upon the process by crimping and then bending the tubing rather than cutting at each crimp. By using this technique, the number of cuts in a 20 foot section of tubing can be reduced from 10 to 2. This is an obvious benefit in time savings and reduces the potential for release. Currently, the project is evaluating options for a power assist with the cutting phase of this operation since the current approach of using long handled bolt cutters is a cumbersome operation and not well suited especially at higher elevations and in cramped spaces. The project is also deploying this technology to a non-rad application associated with removal of breathing air stations at the plant. These stations have no isolation valves and the entire system must be shut done for the removal of one station. There is then a time consuming startup procedure. With the Burndy crimper, a station can be isolated with a total shutdown. It is anticipated that this technology will enjoy additional deployments at both the Mound plant and other DOE facilities.