Gantry Bore Cover Removal and Re-Install

Prerequisites

Overview

This procedure explains how to remove and re-install the CT Gantry rear cover.

ELECTROCUTION HAZARD.
HIGH VOLTAGE PRESENT. Potential for injury if covers removed and power is left “ON”.
DISABLE ALL SERVICE SWITCHES PRIOR TO REMOVING REAR COVERS.

Stop the rotor of X-ray tube in case of Liquid Bearing Tube before HVDC off. Refer to Liquid Bearing Tube Rotor stop procedure for details.

Always turn OFF the HVDC before the 120 VAC. Turning OFF 120 VAC power before HVDC power can result in equipment damage.

Remove gantry side covers, top covers and Mylar window. Refer to each cover’s removal procedure.
Remove gantry rear cover and move away from the gantry. Refer to Gantry Rear Cover Removal procedure.
Disconnect BRTH Light I/F cable and MIC REAR T-SW I/F cable from the top of the bore cover.

Figure 1. BRTH Light and MIC REAR T-SW I/F Cable Connnectors
Connect the terminator to MIC REAR T-SW I/F connector.

Figure 2. Terminal Position
Remove the 2 screws located at two bottom brackets of the bore cover. Then loosen the screw on top. Refer to .Figure 3

Figure 3. Screws of Bore Cover
Pull up safety pin small knob on the bore cover top bracket and rotate 1/4 turn to keep the safety pin disengaged.

Figure 4. Safety Pin

POTENTIAL FOR INJURY TO SERVICE PERSONNEL
WEIGHT OF THE BORE COVER IS ABOUT 20KG (44LKS). SECOND PERSON IS REQUIRED TO ASSIST IN REMOVAL AND INSTALLATION.

With two persons, pull out the bore cover from the gantry stationary brackets and place it on the floor.

POTENTIAL FOR INJURY TO SERVICE PERSONNEL
WEIGHT OF THE BORE COVER IS ABOUT 20KG (44LKS). SECOND PERSON IS REQUIRED TO ASSIST IN REMOVAL AND INSTALLATION.

With two persons, lift the bore cover and attach it to the gantry stationary brackets. Insert the top of the cover bracket to the gantry stationary bracket first.

Figure 5. Bore Cover Attachment
Tighten 3 screws located at top and two bottom brackets of the cover.
Remove the terminator from the MIC REAR T-SW I/F connector and restore it to the original location.
Connect the BRTH Light I/F cable and MIC REAR T-SW I/F cable to the connectors.

Continue with other cover installation procedures as necessary. When AC power is restored to the system, prior to enabling axial drive or HVDC, remember to rotate the gantry by hand to ensure there is no interference between covers and rotating components.
Verify all covers, especially side covers are properly secured.
Ensure there is no interference during all tilt range.