CMS ZDC Remote Exchange Crane

Paul DebbinsUniversity of Iowa

June 26, 2008

Table of Contents

System overview

Subsystem Assemblies, Mechanical Detail and Calculations

Vertical ElevatorRotation CarrierShielding Sarcophagus (Sarco)

Control System

System Overview

Purpose – To remotely exchange the CMS ZDC and a dummy copper absorber between the TAN instrument slot and a separate portable shielding sarcophagus (Sarco)

Design Intent – Eliminate all unnecessary degrees of freedom

Maximize simplicity and inherently reliability.

Provide a fixed motion geometry which is aligned with the TAN offset from vertical. TAN is offset 0.7deg parallel to beam axis (Z) and 0.4deg in X. This allows the insertion/extraction of elements to follow the physical geometry of the slot.

Architecture - 3 main sub-assemblies:

Vertical Elevator - moves elements vertically (almost) in and out of the TAN slot

Rotating Carriage – rotates the vertical elevator (containing ZDC or Cu Bars) between the top surface of the TAN and the sarco positioned alongside the TAN

Shielding Sarco – portable shielded storage for elements outside the TAN

Fixed Hinge Leaves

The following sequence illustrates the concept of the CMS RHS. These are not engineering drawings, and do not represent current revisions to design.

Rotating Hinge Leaves

Vertical Elevator

Vertical Elevator

ZDC Fully inserted in TAN

BRAN

Partial Vertical Extraction

Full Extraction

Partial Rotation

Vertical Elevator rotated onto Pig

ZDC Fully lowered into Pig

ZDC lower into pig. Human intervention then to disconnect ZDC from crane.

Pig is removed, pig containing copper bars put in place, affixed to crane and

procedure reversed. Copper bar module must be built to duplicate the manner

in which ZDC attaches to lift frame.

Vertical Elevator

ZDC HADEM

Drive screws

Clearance over BRAN R/O consumes120mm of vertical space

Vertical Elevator

Dimensioned clearances in Tunnel

Clearance to Survey unit on IP side

Vertical clearance to overhead cable tray

TAN

Tunnel Floor

Vertical Elevator

Dimensions: 1182 (Z) x 243 (X) x 976 (Y)Frame and ZDC carrier are alloy steel - welded constructionCarrier is guided vertically in frame by 4 linear bearings

Drive system are two SilberBlau Merkur series M1 traveling nut screw jacksLow drive ratio (16:1) chosen to minimize input torque and reduce speed of lift travel. @1000 rpm input - lift velocity = 250mm/min. Total lift travel = 610mm. Time to lift = 2.5 min

Prefer slow lift speed (4x greater speed possible) Use of lower power motorsSafer operation of machine Longer lift time not a problem, no human exposure during lift cycle.

Merkur screw jacks are trapazoid type, self locking. Eliminates possibility of load falling from failedmotor, drivetrain, or electrical. Maximum lift capacity (each jack) = 5kN (1,120 lbs) Jacks operate only in tensile load.

Vertical Elevator

Sample drive calculations:

Absolute worst case is lifting full volume of TAN slot of copper bars = 500kg (1,100 lbs)Max lift of Merkur M1 is 2x5kN (2 drives) = 10 kN (~1000kg or 2,200 lbs)

Factor of 2 safety margin over WORST case.

ZDC mass is 235 kg for comparison.

Motor requirements

Input torque (from drive motor) to Merkur unit is 0.35 Nm for 2kn load, 1000rpm input speed. Maximum input torque = 3.4 Nm

Motor selection:

Physical size of motors of this torque range are fairly compact and fit into the allowable spacesaround the vertical elevator. Final specification of motor depends upon radiation hardness. Need to consult with TS group in this regard.

Inspection Survey May 2008

An inspection survey of clearance to elements in tunnel (cable trays, monorail, pipes) was made to have first hand validation of CDD drawings of area. Dimensioned survey shown below. Comparison of survey to CDD drawings shows good agreement between them.

Clearance – Left (+) side

Left Side Inspection Survey Superimposed over CERN drawing. Closely in Agreement. Arrows denoteinspection location of features.

These elements do not interfere as shown overthe location of the ZDC slot

Clearance – Right (-) side

These not presentover TAN region and do not interfere in space

Inspection survey elements superimposed over CERN drawing of Right side TAN. Clearance “envelope”of permissible ZDC handling system comparable between Left and Right sides.

Rotational Geometry Points

Hinge placement geometry for rotating arms. This geometry is close, but needs to fully optimized to selectfinal geometry. This geometry serves to illustrate clearances from Tunnel services and placement of sarcophagus for mating with vertical elevator. Vertical elevator geometry is considered working design.

Rotational Geometry of Vert. ElevatorIllustration of full range of motion of Vertical elevator from top of TAN to mate with Sarco. This range ofmotion is generated from the geometry illustrated in previous slide. This servers to illustrate attainableclearances, optimization of geometry is expected to improve clearances.

Rotational Geometry - Clearance

Cable Tray

PipesOverhead Crane Beam

Minimum Clearances to overhead services as a result of the selected rotational geometry

Rotating Arm IllustrationConceptual Illustration of Rotating Arm assembly and Drive Mechanism. Drive is a traveling screw type, self locking (cannot be driven by load). Final geometry is not yet optimized, and final design is not yetgenerated. Calculations based upon trial geometries have demonstrated clearances obeyed, and loadsare within range of drive mechanism with a safety margin of 2.5 times.

Traveling screw advances intodrive mech. body as rotationis actuated. This allows for clearance to pipes as screw levels to horizontal, it also retreats from backwall.

Available space for Rot. Assy.

93mm

Survey Point

Shielding Sarcophagus (Sarco)

Rotational Geometry places Vertical Elevator in the position dimensioned below

Sarco

It is desirable to be able to move sarco by hand on groundnear TAN for positioning. This could be accomplished withball transfer units on platform. This would also need the incorporation of a system to lock unit from rolling awaywhen stored.

Transport of Sarco should be done by operator positioned at the long end (Z axis) on the side away from the IP.This provides the least activated side. Additional shieldingin Sarco can be provided to gain a “preferred” face.

Space available for Sarco in the geometry of the RHS system is sufficient to allow implementationplus additional room of prelim Sarco design as put forth by KU

Control System

2 axis servo control. 1 axis controls vertical elevator, 1 axis for rotating arm drive.

End limit switches lockout travel past stops.Current limiting at servo motor controller set to prevent redundant protection from overtravel damage. Motor torque is proportional to current, so torque limited below stress limits of structures.

Controllers also permit velocity and position control if needed, but not anticipated to be used.

Controllers provide torque feedback, log file will be generated to track machine performance. Provides the ability to identify any binding or stiction developing over time.

System is intended to minimize operator input. Operator issues start commands and monitors machine remotely with ability to stop on the fly. Operator is removed from area during all excursions of ZDC orcopper absorber outside of TAN or Sarco

Experimentation will provide the answers to the best manner in which to control

Exact motor selection will need definition, also need to consult with TS about rad. hardness of motors.

System will be visually monitored with camera system. Experimentation will demonstrate best camera placement. Camera will be set up on tripods in the area before operation, and removed after.

System is designed to allow full range of operation of both vertical and rotary systems without attachmentto devices in TAN. This allows proving the system before each operation.

Installation on TAN

The installation of the system on the TAN will require only threaded holes on 4 surfaces.

Front of TAN (facing transport zone) : bare holes are needed to match pins on Sarco to fix the Sarco in place, threaded holesare needed to be able to temporarily bolt Sarco to face of TAN

Top of tan needs tapped holes for alignment brackets for vertical elevator

Faceted faces of TAN between top and long sides will need tapped holes to mount rotating arm hinges and swivel mount hinges for SHE traveling screw drive.

NO attachment to TAN are permanent, system can be removed.

System does not protrude into transport area.

What needs to be done still

Optimize rotational geometry and generate complete models of mechanism.

Evaluate final proposed structures for load capability – we have begun talking to Fermilab to obtain structural analysis

Finalize choices for Motors, cabling, switches, lubricants in terms of Radiation TolleranceNeed to work with TS on these matters, to identify preferred devices. Solutions employed in Tunnel such asATLAS crane and Collimators provide a baseline of accepted devices.

Finalize Sarco parameters and design. Ample space is provided. Need to define exact modes of transport expected

Generate revised intervention procedures based on choices made concerning issues above.