DEVELOPMENT OF HIGH INTENSITY BEAM HANDLING SYSTEMAT KEK-PS NEW EXPERIMENTAL HALL
PART II, DEVELOPMENT OF THE QUICK DISCONNECT SYSTEM
Y.Kato, M.Minakawa, Y.Yamanoi, M.Ieiri, H.Ishii Y.Suzuki, M. Takasaki and K.H.Tanaka
Beam Channel Group, Physics Department,KEK, National Laboratory for High Energy Physics,
Oho 1-1, Tsukuba-shi, Ibaraki-ken, 305 Japan
H.Kojlma and K.Kaji
Ishikawajima-Harima Heavy Industries Co., Ltd.
1, Shin-Nakahara-Cho, Isogo-ku, Yokohama-Shi, 235, JapanIntroduction
The magnets of the new counter experimental hall
will be placed in very high radiation field. The
residual radiation level will be over 100 Rem/hat themagnet surface after one normal operation period ( 3weeks). It is almost impossible to maintain themagnets in the beam tunnel. Therefor we need a quick
disconnect system of the magnet from the beam line.
The magnet maintenance will be carried out in a hotlaboratory using remote manipulators in order tominimize radiation exposure to maintenance personnel.
The quick disconnect devices we developed are forcooling water, electric power and interlock signals
for magnet itself, and vacuum flange and pumping port
for beam duct. All the devices are assembled on aniron base plate with the magnet[!]. The base plate
will be put on the floor table placed on the beamtunnel by a over head crane. We employed pivot
fitting system between the base plate and the floor
table for the position reproducibility of the magnets.
The floor table is well aligned and fixed on the beamtunnel. The magnet comes back from the hot cell after
the maintenance will be placed again on the floor
table. The alignment clearance of the pivot fitting
is better than O.lmm. The electric power and"interlock signals of the magnet are connected
automatically between the base plate and the floor
table. The cooling water and the pumping port areconnected by using simple rotation motion supplied
from the outside of the tunnel. The vacuum flanges atthe both ends of the magnet beam duct are also
combined by the same way. The details of thedisconnect system are summarized in the following
sections.

of the connectors are made of ceramics. The
performance of the connectors were tested up to2500A/200V and no serious fault was found in bothcases. The connector for the interlock signals is
simple cannon type 24-pin coupling. All theinsulation parts of the connectors are also replacedby ceramics. The connector itself was loosely boundin the connector mount placed below the magnet baseplate in order to accept some axial umbalance between
the female and male connectors.

Fig.l, The press conductor type power connector.

Electric power and interlock signals
The connectors of the electric power andinterlock signals have the structure of quick
disconnect without any external power, and are joined
automatically by using magnet weight when the magnet
is brought down on the floor table. Therefore theseare set under the base plate of the magnet. We·d-eveloped two types of the power connector.s. One is
the press conductor type and the other is theknife-switch type as shown in Fig 1 and 2. Maximum
current/voltage is DC 3000A/200V in the both types.
The contact surface of the connectors was designed tohave the ability of self-cleaning. In order to resist
for high level radioactivity, all the insulation parts

Fig.2, The knife-switch type power connector.
Cooling water and pumping port
The water joint we developed is the press-joint
type using toggle-link structure as shown in Fig. 3.
The connector size is 2 inches in diameter. The-320-

gasket used is metallic 0-ring CHelicoflex, [2]) andattached on the magnet side so that the gasket is alsobrought to the hot sell and replaced easily. The
pressure of cooling water employed in the newexperimental hall is 20kg/cm 2 • The water connector
was tested according to JIS 20kg flange standard. No
leakage of water was found up to 50kg/cm 2 • The
pumping port has the same structure as the water
connector. The inner diameter of the port is, however,1 inch. The helium leak test was carried out and lessthan 10- 8 !.sec was found.

coupling. For the present development, the K-flange
was re-designed to suit for metallic 0-ring so thatthe flange binder became stainless-ste el collar toincrease the binding force. The new K-flange canaccept the rubber 0-ring and bound by V-band[4J. Inother words, the new K-flange standard is lower
compatible. The inorganic lubrication was employed in
the flange disconnect device. The flange collar was
made of "Devametal" which contains fine carbon powderin the brass body and ensures very low friction at thesurface of the metal. The most parts which need thelubrication were made of "Devametal"[5 ]. MoS2 was not
used because of its long term instability.

Fig.3, The press-joint type water connector using
toggle-link structure.

Vacuum flange
Beam duct should be disconnected at the upstream
and downstream ends of the magnet when the magnet isremoved from the beam tunnel[3]. Therefore a
disconnect device for the vacuum flange was developed
as shown in Fig.4. Before the magnet is lifted, theflange disconnect device is released and the beam duct
becomes 80mm shorter at both sides of the magnet withflange and with the disconnect device itself in orderto clear the facing flanges. The vacuum flange wehave been using is so called "KEK K-flange" which isdesigned by us for rubber 0-ring and bound by V-band

References
1. R.L.Keizer and M.Mottier, Radiation-Re sistant
Magnets, CERN 82-05, June 1982.
2. Helicoflex, the product of Usui Kokusai Sangyo, Co.,
Ltd.

3. M.Goujon and M.Mathieu, Reccord a vide telecommande,
Note Technique SPS/SME/78-240, CERN.
4. V-band coupling, the product of Yokohama AeroquipCo., Ltd.
5. Devametal, the product of Daido Metal Co., Ltd.

-321-