• RRW: "Energy Doubler" appears to be feasible concept (March, 1971)
  

• Colliding beams at Fermilab? (March, 1976)
  

• New milestones in Doubler progress (April, 1976)
  

• POPAE colliding beam design study announced (June, 1976)
  

• Saver/Doubler refrigerators tested (February, 1977)
  

• Flying Fermilab skies (March, 1977)
  

• Energy Doubler reaches new milestone (April, 1977)
  

• Success! Prototype magnet passes test (June, 1977)
  

• A challenge met (July, 1977)
  

• Laying cable at a 5,000-foot-per-day clip! (August, 1977)
  

• Accelerator down, construction up (August, 1977)
  

• Accelerator upgrading , Part II (September, 1977)
  

RRW: "ENERGY DOUBLER" APPEARS TO BE FEASIBLE CONCEPT

Robert R. Wilson, NAL Director, testified Tuesday afternoon, March 9, 1971 before members of the Joint Committee on Atomic Energy of the U.S. Congress in Washington, D.C., on the state of the Laboratory. He said, in part:

"Fortune has smiled on us at NAL since our groundbreaking on December 1, 1968. Our costs have been low enough and our construction has been rapid enough that a larger fraction of the machine is under way, or actually finished, than might other wise have been expected. Indeed, it appears possible now that the accelerator might be in operation this coming summer."

Dr. Wilson spoke about the eventuality of NAL going to 500 BeV. He noted that the JCAE Subcommittee on Research, Development and Radiation had recommended, in 1968, that a continued study be made of the possibility of achieving a higher energy (at NAL) by the use of super-conductivity.

"It appears now that such a possibility may become feasible in the concept of what I like to call an 'energy doubler.' It is a small-bore superconducting magnet that can be mounted 'pickaback' on the present main ring magnet. If successful, it should be of modest cost and should enable us to achieve higher energies -- as much as 1,000 BeV. Just as important, though, is that operation above the 200 BeV level would cost much less using the superconducting magnet than it would using our present copper and iron magnets. In fact, a considerable fraction of the cost of the energy doubler might be recovered in the first years by savings in operating costs. It might also forestall the necessity of installing additional water cooling or of installing devices to smooth out our electrical loads on the power lines...."

"....Because the bore of the new magnets would be so small, because no new tunnel or buildings would have to be constructed, we can hope to be able to build such a device for less than $20 million, possibly even for less than $10 million. All of these considerations, it must be emphasized, are based only on the most preliminary of studies...."

"....If we have done at all well at the NAL, it is in part a reflection of the interest, the eagerness, the ability, the determination of the physicists in this country to explore the existing frontier of knowledge. I would hope that the JCAE, which has done so much to initiate this project, to bring it to this point of reality, to inspire it to over-reach the initial goal, will help it to reach an operational level that will justify what they have accomplished thus far. I would hope, too, that in living up to my commitment to the Committee not to exceed $250,000,000 for construction, the Committee will challenge me to build as extensive experimental facilities and attain as high an energy as is possible without exceeding the Congressional authorization of $250,000,000."

COLLIDING BEAMS AT FERMILAB?

	Proposal for storage ring at Fermilab

Recently a small meeting gathered in the Village to discuss prospects for colliding beam physics at Fermilab. In these schemes colliding beams would be produced by using a storage ring built adjacent to the Main Ring into which the beam of the Main Accelerator would be injected and stored. At a straight section common to the two rings, the beam in the storage ring and the beam in the Main Accelerator would collide. The total energy available in the center of mass of the colliding particles is almost the sum of the energies of the protons in the two colliding beams. Several alternative modes of operation were discussed at the meeting.

Storage rings are not substitutes for conventional accelerators. Rather colliding beam experiments complement techniques used in conventional accelerators. A storage ring system permits study of reactions that occur in energy regions beyond the present state of the art in particle accelerators, namely the Fermilab machine. Searches for certain particles such as the elusive intermediate boson with predicted masses of 60 BeV require colliding beams at Fermilab energies.

Several different possibilities for storage rings at Fermilab were considered at the meeting in the Village. One of the central topics involved schemes for using the Energy Doubler/Saver. The Fermilab Doubler/Saver will consist of a ring of superconducting magnets installed in the present tunnel of the Main Accelerator. The beam from the present accelerator will be injected into the Doubler/Saver and accelerated to 1000 BeV. The possibility of producing interactions between beams in the Doubler/Saver and beams in the Main Accelerator was one impetus for the meeting.

Arrangements for colliding the beam from the Doubler/Saver with the beam from the accelerator depend on the placement of the magnets in the Main Ring tunnel. The further the Main Accelerator and the Doubler/Saver rings are separated, the more difficult it will be to bring beams from one ring to the other, make them cross, and then get them back in place in the 52 meters of long straight section. This plan could provide collisions of beams up to 400 BeV and 1000 BeV, leading to center of mass values of 1,250 BeV.

A second storage ring proposal suggested the possibility of constructing a "small" 25 BeV storage ring at Fermilab to intersect the Main Accelerator at the long straight section upstream of the RF location (straight section E). This proposal would use conventional magnets and have a ring with the same radius as the present Booster Accelerator. Interactions would occur as the Main Accelerator is ramping, much as the present arrangement with the jet targets at the Internal Target Area.

With the Main Accelerator or the Energy Doubler/Saver operating at 400 BeV, the system would give center of mass energies of 200 BeV. This design has been submitted to the Program Advisory Committee as an experiment for an intermediate boson search by an experimental group consisting of Russ Huson, Phil Livdahl, Rae Stiening, Lee Teng, Frank Turkot, and Jim Walker.

	Main Features of Proposed Storage Ring Facility

The possibility of matter-antimatter colliding beams was also reviewed at the meeting. An interesting attack suggests a small storage ring that would collect antiprotons produced by first making antiprotons in collisions of the main ring proton with a normal target. A race track-shaped field with ends three meters in radius would be used to accumulate 2 BeV antiprotons produced by the Main Accelerator. These antiprotons would be cooled using a several amp, 1 MeV electron beam. The antiprotons are cooled by the electrons, so that they oscillate less in their swing around the accelerator and more can be fitted into the machine. Designers estimate that perhaps 4 x 10⁷ antiprotons could be stored per cycle until about 101° were accumulated. These antiprotons would be injected back into the Main Accelerator and accelerated backwards simultaneously with "right way" protons. Theories claim that antiproton-proton collisions lead to higher production of intermediate boson particles than do proton-proton collisions.

Storage rings exist at several other research laboratories in the world. Among these are the electron-electron colliding beam facilities at SLAC, the proton-proton facility at CERN, the electron collisions at Novosibirsk, U.S.S.R.. Others are located at the Frascati National Laboratory in Rome, the Orsay Laboratory in France, and in Germany. In the United States, construction of a new set of large intersecting electron storage rings have been approved at SLAC (the PEP project).Brookhaven National Laboratory is proposing to build a set of proton storage rings dubbed ISABELLE.

NEW MILESTONES IN DOUBLER PROGRESS

	Charles Hess preparing leads for vertical dewar tests on a 22 ft. Doubler magnet			Louise Latreille and Wally Habrylewicz study model of new Doubler plan

	Scanning electron micrograph of a strand of superconducting wire for the Fermilab Energy Doubler, magnified 500 times, showing 2,200 individual filaments of niobiumtitanium embedded in a copper matrix. The wire is but 0.027 inches in diameter

The first 22 ft. bending magnet for the Fermilab Energy Doubler passed a performance test on March 12. This is the first magnet produced on the new production line that started January 20th. Magnets for the Doubler will be produced at the rate of one each month, with production increasing as they are installed in the Main Ring.

Location of the Energy Doubler in the Main Ring tunnel has been changed. It will be located below the present Main Ring instead of at the top of the tunnel enclosure. The two beams will now be 18 inches apart vertically, and aligned horizontally. Beam manipulation between the two rings will be easier and colliding the two beams becomes a possibility.

Photo courtesy Airco.

POPAE COLLIDING BEAM DESIGN STUDY ANNOUNCED

	Proposed location of POPAE

A design study for a 1000 GeV on 1000 GeV colliding proton beam storage ring facility to be located at Fermilab has recently been completed. The design study was the result of a collaboration between Argonne National Laboratory and Fermilab, which began in the fall of 1975 under the direction of Robert Diebold of Argonne.

The construction of such a colliding beam facility (denoted by the acronym POPAE: Protons On Protons And Electrons) at Fermilab would take advantage of the substantial national investment in the facilities of the Laboratory. The present accelerator is itself a uniquely suitable device for filling storage rings with high energy protons, and in a few years the Energy Saver/Doubler will increase the available proton energy to 1000 GeV. The research capabilities of Fermilab would be extended in a natural and complementary way by the addition of the proposed proton storage rings.

High energy storage rings are being considered at other laboratories. Brookhaven National Laboratory has proposed a 200 GeV on 200 GeV proton-proton colliding beam facility, Isabelle, which would accelerate the protons from a 30 GeV injection energy. CERN has studied the possibilities of 400 GeV on 400 GeV storage rings, which like POPAE would receive protons from an accelerator at the desired energy.

At present, the ISR at CERN is the world's only proton-proton colliding beam machine. This facility gave an enormous increase in useful energy over that previously available, up to an energy equivalent to that of a 2000 GeV fixed-target accelerator. However, this energy has since been approached by Fermilab.

For further energy increases, however, colliding beams quickly outstrip the useful energy of fixed target machines, even those that might conceivably be built as part of a World Collaboration. In terms of equivalent fixed-target machine energy, POPAE would provide a factor of 1000 increase over the ISR. An equivalent fixed target machine would circle the North American Continent. The phenomena found in the energy range spanned by the previous factor of 1000, going from 2 GeV up to 2000 GeV at the ISR, have profoundly changed our understanding of nature and indeed encompasses the whole history of elementary particle physics. There are some ideas of what may be found as the frontier advances beyond present energies, but considering the surprises in the previous factor of 1000 it seems probable that these expectations will pale beside the phenomena which will actually be discovered.

The interest in colliding beams at Fermilab goes back to the site-selection days when one of the site-selection criteria was that space be available to accommodate future storage rings. Indeed, the State of Illinois went to great expense to provide this capacity in the land purchase.

In the fall of 1975, Robert Sachs, the Director of Argonne National Laboratory, suggested that Argonne and Fermilab collaborate in a joint design study for POPAE. This suggestion was welcomed by Robert Wilson, the Fermilab Director, and since that time a joint Argonne-Fermilab team has been actively developing the detailed conceptual design. Although the present design does not include detailed provisions for electron-proton collisions, these provisions can be incorporated by the later addition of an electron storage ring with a minimum of disruption and cost.

The design study proposes that the two rings of POPAE be housed in a common tunnel of circumference 5.5 km (slightly smaller than the 6.3 km of the Main Ring). The machine would be located on the Fermilab site in an area bounded by the Main Ring, the Proton Laboratory, and the Village, a region rather level and free of obstructions. This location results in nearly straight injection lines to the storage rings. These lines would consist mainly of buried vacuum pipe with quadrupole doublets every 150 meters for focusing, and would be relatively inexpensive both to build and to operate. One of these lines would originate at the "Q stub," located in the Proton Laboratory beam line, and the other from a new extraction point at the B straight section. Each storage ring would be composed of six 720-meter long curved sections, separated by 200-meter long straight sections where the beams are focused and intersect one another.

To fill one ring to the design value of 5 A would take 6 x 10¹⁴ protons, 66 accelerator pulses at 10¹³ per pulse. The time to do this would range from a few minutes at low energies to about one hour at 1000 GeV. Each ring would be able to store high beam currents at energies between 100 GeV and 1000 GeV, and unequal-energy operation would be possible as required by experiments.

Superconducting magnets have been specified for POPAE in the design study. Superconducting magnet technology has been moving ahead in the past few years to the point where one can confidently predict its successful application to high energy storage rings. A field of 60 kG at 1000 GeV has been used in the design study. This field is somewhat higher than the 40 to 45 kG design of the Energy Saver/Doubler. A 60-kG dipole magnet of a design rather similar to that considered for POPAE has been built and operated by H. Desportes and his colleagues at Saclay, and this field strength would appear to be a reasonable goal for the next step in accelerator technology.

Ron Walker (L) and Bill Fowler, Assistant Head, both of the Superconductor Group, were on hand last week when the first piles were driven for the start of construction of a central helium liquefying plant at Fermilab. Located west of the Magnet Facility, the 50' x 180' plant will be similar to the plant in California (see photo at right) from which surplus Air Force equipment is being obtained. The plant, scheduled for completion in the fall of 1977, will provide liquid helium for the energy doubler superconducting magnets.

The design study estimates the total construction cost of the facility, including engineering, architectural costs and contingency to be $245 million in 1976 dollars.

SAVER/DOUBLER REFRIGERATORS TESTED

	Vic Garzotto (L), Rick Diehl clean helium expansion engine developed for Saver/Doubler refrigerator			Tony Rader (L), Dick Brazzale at first stage compressor for helium satellite unit in Lab 2 in the Village

A successful test of the prototype of the refrigeration system for the proposed Energy Saver/Doubler at Fermilab was completed last week by the Cryogenics group of the Accelerator Division's Saver/Doubler section. The cold box and engines of one of the "satellite" refrigerators were tested in two of their three modes of operation in preparation for similar use in the early stages of Saver/Doubler operation.

	Paul Furio, Ron Norton, Claus Rode at prototype control center

Twenty-four of these units will comprise the cooling facility that will maintain the -450°F. temperature of the Saver/Doubler superconducting magnets. Each of the satellite stations will form an independent module, cooling 43 (1/24th) of the magnets in the new ring, through a pump loop that will start and end at each service building around the accelerator ring.

The same units will also be produced for use with the superconducting magnets to be installed in the beam switchyard to accommodate beams of 500 BeV and higher energy when these become available. Another dozen or so of the refrigeration units may be used in the experimental areas, particularly in the superconducting magnets manufactured for the new Pion Beam line in the Proton Area.

Claus Rode, who heads the Saver/Doubler group that made the successful test, reports on the cryogenic progress, "Our Doubler refrigeration units have been in design and development for several years. We first had to develop a way to pump liquid helium much like water. This has been done during the last three years, mainly using a 400 ft. long loop built in the old protomain. Don Richied and Cryogenic Consultants Engineering Company carried the main responsibility for this work.

"We then turned to studying with the Switchyard Group the effects of the proton beam on a prototype superconducting magnet which was installed in the extracted beam line in the Transfer Hall and in the B-12 service building."

	Mike Hentges (L), Jack Johnson at refurbished compressor of purification system

"We have installed a second pump loop which utilizes 2 CTI 1400 helium refrigerators at B-12 for testing a string of magnets in the B-12 service building, where the program is to study the cryogenic aspects of strings of magnets."

The satellite units will combine with the central helium liquefying plant, also under development at the intersection of Roads B and D, adjacent to the Magnet Facility. The next test by the Doubler Cryogenics group will be a trail of the "liquid user" mode in the satellites. This test will simulate the use of about 90 liters of liquid helium per hour in the refrigerators, that would be supplied by the central liquefying plant. The helium vaporizes in the course of its use in the magnets and is returned to the central plant for re-liquefying.

The large capacity of the central plant will give the Saver/Doubler greatly increased efficiency of operation. A former liquid propellant plant acquired by the Laboratory from the GSA excess property listing, this plant formerly supplied oxygen/nitrogen to the missile program in California. The components are being refurbished and the larger part of the plant will be moved to Illinois to serve the Saver/ Doubler project.

Present scheduling calls for the plant to come into operation in the fall of 1977.

FLYING FERMILAB SKIES

	Tying down cable to a tractor before takeoff
	Helicopter crosses main ring cooling ditch to pick up another load
	A cable caravan preceded "air drop" by helicopter

Assignment: Lay three 5,000-foot electrical cables, each weighing 7,500 pounds, in water. Solution: Hire a helicopter!

That's what Accelerator Division did last week to improve 15,000 volt feeder cable lines between service building D-2 and C-Zero on the Main Ring. Three aluminum cables, each 1¼ inch in diameter, were laid in the ring's inner ditch and the connecting inner ring lake in that area. "Zero" hour was 7:30 a.m. Monday, March 14. Under a cold overcast prairie sky, project manager Jan Ryk and other personnel assembled. Capt. John Hays of security had sealed off general access to the work area, issuing red "emergency" badges for workmen and authorized observers. They included Ed Kessler, accelerator support power supply; Bob Adams and Bob Scherr, safety engineers; and The Village Crier.

A 15-man crew represented the contractor, Premier Electric Co. of Aurora. And the star performer, the chopper, was supplied by Midwest Helicopter Airways, Inc. of Lyons. Pilot Bob Gaylord did the flying with radio directions from the ground by two other pilots, Jeff Hennard and Bill Kelly. Gaylord had flown in on two earlier days to scout the proposed route of the cable. The day of the event, he arrived early enough to walk the path. Since the rated load of the helicopter is 4,000 lbs., it could not handle a reel of cable. So the approach was to move the reels along the road on carts, unreel some of the cable along the road and move this unreeled cable by helicopter toward the inner ditch.

Looking like a circus-wagon procession was a string of three farm wagons, each mounted with a cable reel boxed-in on the wagon bed. The wagons were pulled by a truck. A tire company truck loaded with spare rubber for the farm wagons stood by.

According to Jan Ryk, Accelerator Division Head Russ Huson and the contractor came up with the helicopter idea simultaneously. Original strategy had been to lay the cable on ice in the cooling ditch and lake--then wait for the ice to melt, dropping the cable under water. The plan went awry when: 1. An early spring thaw melted the ice, and 2. The cable arrived behind schedule from the manufacturer, Phelps Dodge Cable and Wire Co.

Before the helicopter lifted off, the cable was tied to a tractor stationed near D-2 service building. This was done to give the pilot a stationary object to pull against. Pilot Gaylord went up initially for 30 minutes, taking the wires across the cooling pond and the inner ditch to another tractor awaiting on the inside of the ring. After another tie-down, the copter trailed the cable in the inner ditch to the inner lake near the C-4 service building area. Here the protruding pump station had to be encircled by an excursion into the lake. This operation turned out to be rather tricky. The main battle here was fought by two laborers in a row boat on the lake. They tried to tie down the cables while fighting the fierce down draft of the helicopter.

This part of the operation was accomplished by running a tie line to a tractor inside the ring, then the cable was airlifted into the lake and the inner ditch to the C-zero area.

The project was completed in three hours' flying time. "It went very smoothly," Ryk said later. "nobody got hurt. The cables were tested at 55,000 volts after the installation. Even so, there was a little bit of tension during the operation because we had never tried anything like this before and everything was moving quite fast."

ENERGY DOUBLER REACHES NEW MILESTONE

A major milestone in the development of the Fermilab Energy Doubler was reached at noon on Friday, April 8, 1977. A string of four superconducting magnets was energized for the first time and reached 4,300 amperes, the equivalent of 1,020 BeV beam energy in the eventual Doubler plan. The test demonstrated that these magnets, specially-developed for the Energy Doubler, can be successfully operated in series, an important consideration in building a superconducting accelerator. Designers of superconducting accelerators which use assemblies of multiple superconducting magnets have always been concerned about the protection of such a magnet system in case of the malfunction of one magnet. In these tests it has been demonstrated for the first time that a series connection of magnets can be protected from such a malfunction and that such a system can be operated successfully.

In the projected design of the Doubler, about 780 of these magnets, plus 250 quadrupole magnets, will be installed in a ring directly below the magnets of the present Main Ring. Beam of 100 BeV energy from the present accelerator will be injected into the superconducting ring and accelerated to 1,000 BeV, or "double" the present maximum energy of the Main Ring. The use of superconducting magnets instead of the conventional iron magnets will also make possible a substantial saving in the electrical power required to run the Main Accelerator.

Tests of these multiple magnets are being carried out at "The Awning," a small building on Main Ring Road between service buildings B-0 and B-1. The recent success is the result of almost one year of effort by the Energy Doubler group, the Magnet Facility, and other groups in the Accelerator Division. The major purposes of the tests are threefold (1) to investigate the cryogenic properties of several magnets connected together (called "strings")--that is, to learn how these magnets perform at the -450°F. temperature at which the Doubler will operate; (2) to test the various schemes for protecting the magnets if they undergo transition--called a "quench"--from a superconducting state to a state of normal conductivity; (3) to obtain installation and operating experience with Doubler magnets; (4) to develop hardware and software using the present accelerator control system to monitor the operation of superconducting magnets.

	Visitors and doubler group members with one of four magnets tested recently			Phil Livdahl congratulates doubler associates on their achievement

A superconducting magnet is made from wire that is much smaller than the copper bus used to make normal magnets. A superconducting magnet can sustain high currents because the wire, when cooled to liquid helium temperatures (-450°F.) by a super-refrigerator, exhibits the property of superconductivity--that is, it has no resistance, and it is not heated by the current going through it. If some part of the wire leaves the superconducting state, which can happen if the current is raised too high, the wire could be burned up, destroying the magnet. To prevent this, a resistor is switched into the energizing circuit to dissipate this magnetic field energy. When this is done, voltages as high as 1,800 volts are generated across the magnet and pressures as high as 100 psi are developed inside the helium vessel.

In the test just completed, the magnets "quenched" at 4,300 amperes. They have since been run to high current and have been quenched numerous times. The fact that the multiple magnet string behaves in a predictable fashion and can withstand quenches gives confidence that a superconducting accelerator is technically feasible. During the operation of the Energy Doubler, a "quench" will be a rare occurrence, but the Fermilab developers must know from the outset that the magnets can recover from quenches quickly and with no damage.

Developers of the Doubler, who work on the edge of a new field of technology, say they have now answered some important questions about their pioneering project: (1) If the quench occurs on one magnet, it does not, in general, start a quench in adjacent magnets; (2) The vessel which carries the liquid helium is able to withstand the high pressures developed during a quench; (3) Magnets can withstand the high voltages generated during a quench; (4) The electrical safety system designed for the Doubler system is sufficient to protect the magnets from self-destruction if the quench occurs; (5) The cryogenic system performs as predicted. It appears that long strings of magnets can be cooled and maintained at liquid helium temperatures.

The next step in the "Awning Test" program is to run the magnets continuously for a month to see if there is any change in their performance. After that, the string will be extended to eight magnets, then to sixteen magnets.

At the conclusion of the tests Friday, Phil Livdahl, Assistant Head of the Doubler Group, commented, "The tests are the most significant in the two years of development work in demonstrating that the whole Doubler can be built and that it will work." Livdahl told the personnel involved in the Doubler work, "When we have this entire test facility working as a unit we'll have gained an enormous amount of confidence in the system. I'm certain that we have the people here that can do it."

Peter Limon, physicist in charge of the test, said, "A project of this scope could not be done without the dedicated work of scores of people at Fermilab. The list is long of such people, but we want to particularly thank the people in the Doubler Group, the Accelerator Controls Group, the Electronics Group, and Mechanical Support Group, the Magnet Facility, and the many others who gave that little extra bit that made this success possible."

SUCCESS! PROTOTYPE MAGNET PASSES TEST

	G. Kalbfleisch (L) and J. O'Meara beam about successful magnet test
	Engr. Servs. Design Group L-R: N. Avgerenos, R. Roth, A. Oleck, W. Robotham, N. Engler, R. Jornd. Not shown: H. Barber, J. Winterkamp
	Right Photo, Magnet facility crew L-R: C. Bowling, A. Ruffins (kneeling), R. Barnh4ll, L. Dangleis, S. Faulhaber, D. Smith (rear), D. Fisher, J. McBride, D. Truong, M. Frett (rear). Not shown: C. Harris. J. Kiehn

Progress in the research involved in building the Energy Doubler/Saver accelerator at Fermilab took another step forward recently. A successful test was carried out on the first prototype quadrupole magnet for the new ring. The project followed about six months' effort by "the quadrupole team".

In the present design, the Doubler/Saver would consist of 240 of these quadrupoles (together with 800 dipoles). The new ring would be installed in the existing tunnel, directly below the magnets of the main accelerator. The quadrupole magnets focus the proton beam so that it will travel in the center of the 2" x 4" vacuum tube as it races around the four-mile ring about 47,000 times a second.

Previous tests in the Doubler/Saver development reported in THE VILLAGE CRIER have involved the dipole magnets which bend the beam into its circular path. Both types of magnets are necessary, as is the case in the present accelerator.

Design work for the quadrupole magnet was led by Norman Engler of Engineering Services. The fabrication team was led by Don Smith of the Magnet Facility. George Kalbfleisch of the Energy Doubler group is in charge of the program, and John O'Meara of Engineering Services is the project engineer.

O'Meara commented on the test, "Our objective was to build a precision quadrupole using precision rigid coils that maintain their position under magnetic loading. We feel that this objective was met, a design gradient of 25 kilogauss/inch was reached. In doing this, the quad ran at 98% of the maximum theoretical current that the conductor can carry commonly referred to as 98% of short sample. These preliminary tests indicated that the field quality is excellent, however further tests using more precise coils will be conducted during July."

A CHALLENGE MET

	Coils/Cryostats Await Assembly			Completed Magnets after Production Exercise

Henry Ford, father of auto mass production techniques, would have been proud.

Adapting the automaker's theories to high energy physics, Fermilab magnet makers recently won a race with time -- and under strict quality control standards -- to produce a key energy doubler magnet component.

Called a cryostat, the assembly is a sheetmetal vacuum bottle. It surrounds superconducting coils at the heart of electromagnets that will accelerate protons around the main ring for 1-TeV experiments. Some 1,000 magnets are planned for a superconducting ring proposed in the Energy Doubler Project -- a program designed to yield increased useful energy for research while saving electricity and money.

Will Hanson, magnet facility manager, says the one-a-day cryostat production trial confirmed a speculation: that the assembly could be turned out relatively quickly using industrial methods. Jack Jagger, assistant manager, added that the production goal was reached ahead of schedule -- in a relaxed but productive work atmosphere -- and with high morale by 17 crew members. "No panics, other than 'normal' panics," occurred, he said. Jagger noted too that no overtime was required: and that man-hours per cryostat assembled averaged 160, significantly under the 200 figure that had been projected.

The project got underway at 7 a.m. Monday, June 21, in the magnet assembly building. Guiding the handpicked crew in addition to Hanson and Jagger were: Steve Barath, chief technician; Don Tinsley, assistant chief technician; and Jim Humbert, chief inspector; and lead men on day, night and midnight shifts, Wally Medernach, Steve Kovacs and Jesse Mendoza, respectively. Louis Greenwood, expeditor, was also cited for his contributions in making sure that all parts were on-hand when needed. A week of preparation preceded the simulated production run. Small group orientation meetings briefed workers on the how and why.

According to Hanson, each magnet required about 18 major production steps and another 13 major inspections. However, each major production/inspection step involved from five to ten separate other operations.

All operations had been pre-diagrammed in a work flow chart. This workers' "Bible" was co-written by George Biallas, design engineer with Bob Powers, Energy Doubler group consultant. The directions, Jagger said, proved true generally but were modified as needed to improve the assembly process.

Welding was a critical part of the procedure. To fuse the thin stainless steel into a leak-tight system, heliarc welding was specified. A cloud of helium gas acts as a shield for the electric arc. The helium combats impurities and oxidation while providing top integrity welds which withstand the shock of operating from room temperature down to 40° above absolute zero.

An individual "dossier" chronicling the work completed on each magnet traveled with it through shift changes. As production and inspection steps were completed, appropriate personnel initialed and dated the entries in the traveling forms.

Begun on Monday, the first magnet emerged complete on Thursday night -- a day ahead of schedule. Successive magnets were completed at a one-a-day rate.

"The real significance," Hanson said, "was that we proved that completed magnets can be produced by industry and/or ourselves within budget and a tight time schedule." 1979 is the goal for installation of the superconducting ring.

After the work was over, supervisors and crew members held a victory picnic at the Village Barn to celebrate.

A previous simulation, in which coil bundles were fabricated, was successfully conducted in April.

Photos clockwise from left: Magnet is inserted into cryostat. J. Fay welds "can" shut; W. Medernach, G. Sliwicki insert beam tube; C. Hess, J. Jagger, D. Taylor prepare conductor lead; and B. Condor, J. McBride

LAYING CABLE AT A 5,000-FOOT-PER-DAY CLIP!

	"Super-trencher" cuts hole for cable
	Mobile transporter lays cable on sand bed
	Applying sand overlay before backfill

Jan Ryk was skeptical. The project manager on a main ring feeder improvement program had just heard an installation contractor claim he could lay electrical cable at the rate of 5,000 feet a day. Jan became a believer.

The second half of a MR feeder improvement was completed recently. The object of this part of the project was to install additional main ring feeders to service building F3 and E1. Two new tri-cable feeders, with some reconnection of four existing feeders, will increase the capacity and improve the reliability of the western half of the main ring pulsed power system.

Each feeder consists of three cables. A cable is comprised of an aluminum conductor, covered with a layer of insulation rated for 15,000-volt operation. On the outside of the insulation is a helical layer of copper wire which forms the neutral conductor.

Diameter of cable is approximately 1-¼ inches. The total length of the cable installed under this project was about 45,000 feet. The cable arrived at the Laboratory in June, 1977, on nine reels. Each reel contained about 5,000 feet of cable and weighed about 7,500 lbs.

The cable was buried 3 feet underground, along the inside perimeter of the main ring cooling pond. In the operation, a motorized trencher was used to dig a hole 3-½ foot deep and 10" wide. Behind the trencher came a sand dispenser that deposited a six-inch layer of sand in the trench bottom.

Next, cable was laid on the sand bed. Special reel-transport equipment managed the cable reels. "The operation was quite simple," Ryk said. "No cranes were needed for reel handling. The reel-transporter was simply tipped up to accommodate the reel axle and tipped down to pick up the reel.

"A tractor was used to pull the reel-transporter. Since the ground was dry, the reel transporter was pulled along straddling the trench. This made the cable installation a simple operation with a minimum of stress on the cable."

After three cables had been laid in each trench, the sand dispenser put another 6-inch layer of sand on top of the cables. Planks of wolmanized weather treated wood, 1"x 6"x12', were then put on top of the sand followed by back fill. The "sand sandwich" protects the cable against damage by rocks in the soil.

Using the techniques described above it was possible to install a 5,000 ft. stretch of feeder in one 8 hour day--including trenching, cable installation, sand and planks. The back filling took another 8 hour day.

Besides Ryk, other Laboratory personnel participating were: Russ Huson, Accelerator Division head; Gerry Tool, head-accelerator electrical support section; Ed Kessler, Accelerator E/E; Bill Riches, plant support; and Ken Sceper, plant utilities.

Phase I of the improvement carried out in March consisted of laying three 5,000-foot cables by helicopter along the eastern perimeter in the ring's inner ditch and connecting inner lake.

ACCELERATOR DOWN, CONSTRUCTION UP

	Central Laboratory (east) overlooks transfer hall work
	Power shovel strips berm from beam pipe

"Facility M & D." That lone notation is chalked on the daily schedule blackboard in Fermilab's operations center. The message went up at 7 a.m. Aug. 15, 1977 -- when a major facility maintenance and development shutdown began.

Rest for the accelerator means feverish activity for Accelerator and Architectural Services personnel. Two construction projects were planned to take advantage of suspended operations. Working against the Monday, Sept. 12 startup date are subcontractors extending the transfer hall and also completing phase two of a reserve injection to the Main Ring.

Bruce Chrisman, executive assistant in Accelerator, provided details on the transfer hall extension. He said the project is underway directly east of the Central Laboratory, with some parking spaces sacrificed temporarily for construction operations and material storage. A 120-foot concrete tunnel is being constructed from its present terminus to enclosure B in the switchyard. The tunnel will replace the present beam pipe buried 25 feet underground. Benefits of the project will include upgraded electromagnet capacity and increased protection for switchyard personnel against low-level radiation contamination.

Work began a week before the shutdown, Chrisman said. The dirt berm over the beam pipe was stripped down to a safe height above the beam pipe elevation. The remaining earth shield was removed when the accelerator was turned off. Earth closest to the beam pipe will be stored -- under cover -- and go back into the hole first at the project's completion.

A sand footing and underdrain will precede pouring of a concrete slab footing for the tunnel sections. The slab, 14 inches thick by eight feet eight inches wide, will support 11 precast tunnel forms. In an inverted U-shape, each form weighs 33,000 pounds and measures 10 feet long by six feet wide and seven feet high.

The sections will be connected with welded plates. Also, they will be waterproofed between sections. The berm will be reconstructed, as will the parking lot, to complete the project Chrisman said. Other supervisors on the project are Howard Casebolt of Accel. Safety and Marv Warner, Architectural Services. In addition Peter Gollon (Radiation Physics) has supplied manpower and advice throughout the project. The subcontractors doing the work are being coordinated by Don Smith and Bob Maleto of Fermilab T&M Services.

ACCELERATOR UPGRADING, PART II

	Reverse injection construction

Previous week's Village Crier spotlighted the Accelerator Division's transfer hall extension. This week we look at another Accelerator project coinciding with a Laboratory maintenance and development shutdown (Aug. 15 - Sept. 12, 1977): the second stage of a three-phase project installing a reverse injection (RI) tunnel from the booster area to the Main Ring (MR).

The RI tunnel, according to Accelerator executive assistant Bruce Chrisman, will be used in colliding beam efforts. Colliding beam facilities are an integral part of Fermilab's Tevatron project, a new high energy physics range -- 1,000 GeV (1 TeV).

As in the transfer hall project, Chrisman said, RI work began before the accelerator was turned off. From the MR's F-2 service building west, an earth berm over the MR enclosure was removed and backfill excavated from both sides of the MR for a length of 240 feet. Remaining berm was removed after beam shutdown. Then an eight-inch diameter hole was bored through the 16-inch-thick MR wall for a 70-foot beam pipe extension.

Next, a base concrete slab -- 14 inches thick by 8 feet 8 inches wide and 130 feet long -- was constructed for the beam enclosure, access enclosure and access shaft. The slab will support 13 U-shaped tunnel elements and four comprising a labyrinth. Each element weighs 33,000 pounds and measures 10 feet long by six feet wide and seven feet high. After a power crane places the elements, connections will be welded and joints sealed.

This phase of the RI tunnel is a full scale tunnel that will be utilized for targeting an extracted beam of 80 GeV for anti-proton production.

Beam pipe -- 10 feet of six-inch diameter sections and 60 feet of 12-inch diameter -- will be aligned, field welded ant tested by Fermilab personnel. The berm will be reconstructed over the MR and a berm will be constructed over the new MR enclosure to complete the project.

Phase 1 consisted of installing 20 feet of beam pipe from the booster and 80 feet of four-foot diameter sewer pipe enclosure east from the booster. Phase 3 will connect the first two sections with 1,100 feet of tunnel enclosure.

Besides Chrisman, overseeing the reverse injection project are: Marv Warner, Architectural Services; Howard Casebolt, Accel. Safety; Tom Pawlak, project engineer; Mike Mascione, construction coordinator; and Bill Testing Alignment and Survey.

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Robert R. Wilson - Main Ring Accelerator

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