From: 12/5/01 8:17 PM Subject: NTX magnet meeting 12/05/01To: David N Beck ?DNBeck@lbl.gov?, David L Vanecek ?DLVanecek@lbl.gov?, Craig Peters ?C_Peters@lbl.gov?, "Simon S. Yu" ?SSYu@lbl.gov?, Mark Franks ?RMFranks@lbl.gov?, Gary Ritchie ?GRitchie@lbl.gov? NTX magnet meeting and other progress 12/04/01. D. Beck, G. Ritchie, C. Peters, D. Shuman, D. Vanecek, S. Yu present 1. Winder/Stretcher (D. Vanecek) Most parts are finished and the winding shoes and backer blocks were evaluated. Gary will try to ream out the pin holes for easier removal, and the shops will cut a 15 degree bevel on some of the backer block steps to avoid the possibility of a drooping wire getting scraped during winding. We should update the drawings with this feature for future reference. Gary will make coil winding his first priority when he becomes available mid December. 2. Arc bender (D. Vanecek): The steel 12.75 inch diameter pipe will be cut to a 11.875 diameter to start. The design is about 60% complete. Dave will make finishing the design his first priority, as soon as the lamination drawing is complete and an RFQ set in motion. This is expected to occur early next week. 2. Coil Form (D. Beck): This drawing is near completion, though the mandrel interface may require an additional detail or two. Samples were inspected and looked very good, though cleanliness could be better. Gary will clean these in 58 with the "house brew". David Beck will ask about UHV cleaning procedures for G-10 to see if there is one, though the material is not generally used in UHV applications. 3. Mandrel (D. Beck) C. Peters showed a reference indicating that G-10 laminates had lower thermal expansion coefficients in-plane than aluminum. This opens up the possibility of using a thermally removable mandrel without relying on transient temperature differentials. LN2 temperatures should produce a differential radius change of .012" from room temp. D. Beck, and D. Shuman will meet with Al Salazar on Thursday to discuss their requirements and get their approval. The mandrel should have an interference fit of 0.0-0.003" on the diameter at room temp, which would allow inspection and potting without distortion. Additional fixation for machining would be accomplished by engaging the end notches with end plates. The mandrel would be easily removable without going all the way to LN2 temperatures, which is important for safe removal from the finished magnet casting. It will be important to thermal cycle the mandrel in LN2 after final heat treatment and before final machining to finished diameter. Similarly, the G-10 stress relieving should be done off the mandrel, as high tensile stresses and resultant creep may occur in the G-10, resulting in a loose fit on the mandrel after cooling. Tubes should be stood on end during stress relief to avoid ovalizing tubes. Other proposals for mechanically expandible mandrels will also work but are complicated to make and use. 4. Magnet Lamination Dwg. (D. Vanecek) An additional bolt hole was added to each octant to help maintain end plate flatness. This is a smaller hole (9/16" dia) to avoid excessive encroachment into the flux carrying area. A simpler datum scheme has been employed to simplify assembly and measurement tooling. This drawing should be finalized this week. An RFQ will be pursued Monday. 5. Alignement of Mangets on experiment (C. Peters) Discussion on alignment of the magnets and source on beamline (without beam tube in place) indicated that the end notches on the coil forms would be sufficient for mounting cross hair targets in the center of the magnet that could provide alignment both translationally in x and y plus rotation in z. A scythe shaped target plate that fit into diametrally opposed notches and providing a set of targets on the "handle"would allow survey and alignment of magnets off to one side with the beamtube in place. It is not anticipated this will be necessary, however. --------------------------------------------------------------------- Derek Shuman ?DBShuman@lbl.gov? Mechanical Engineer Lawrence Berkeley National Laboratory Derek Shuman Mechanical Engineer ?DBShuman@lbl.gov? Lawrence Berkeley National Laboratory HTML Mail Mailstop 47-112 1 Cyclotron Rd. Fax: 510-486-5392 Berkeley Work: 510-486-4662 CA Conference Software Address 94720 Default Directory Server Additional Information: Last Name Shuman First Name Derek Version 2.1