CEMA STANDARD NO: 352-2012 Approved: September 2012 CEMA STANDARD NO:19, 352-2012 SCREW CONVEYOR SAFETY OPERATION AND MAINTENANCE MANUAL Provided by the Members of the Screw Conveyor and Bucket Elevator Section of the Conveyor Equipment Manufacturers Association as a service to the industry ISBN: 978-1-891171-43-7
CEMA STANDARD NO: 352-2012 DISCLAIMER The information provided herein is advisory only. These recommendations provided by CEMA are general in nature and are not intended as a substitute for professional advice. Users should seek the advice, supervision and/or consultation of qualified engineers, safety consultants, and other qualified professionals.
CEMA STANDARD NO: 352-2012 TABLE OF CONTENTS SECTION A - SAFETY Page 1 PDF Page 5 SECTION B - INSTALLATION Page 4 PDF Page 8 SECTION C - OPERATION Page 10 PDF Page 14 SECTION D - MAINTENANCE Page 11 PDF Page 15 SECTION E - SHUTDOWN AND STORAGE Page 12 PDF Page 16 SECTION F - TROUBLESHOOTING Page 15 PDF Page 17 Page 16 PDF Page 19 Bolt Torque Guide ii.
CEMA STANDARD NO: 352-2012 INTRODUCTION The Screw Conveyor and Bucket Elevator Engineering Committee of the CEMA (Conveyor Equipment Manufacturers Association) Engineering Conference was assigned the task of bringing together, under one cover, the accumulated experience of many individuals and their companies in an effort to provide a common basis for the safety, operation and maintenance of screw conveyors.
CEMA STANDARD NO: 352-2012 SECTION A - SAFETY Screw conveyor safety begins with a plan that considers every possible danger and potential hazard. Operation and maintenance personnel must be thoroughly trained in safe operating procedures, recognition of possible hazards, and maintenance of a safe area around screw conveyors.
CEMA STANDARD NO: 352-2012 CEMA Document: SC 2004-01 WARNING AND SAFETY REMINDERS FOR SCREW , DRAG , AND BUCKET ELEVATOR CONVEYORS APPROVED FOR DISTRIBUTION BY THE SCREW CONVEYOR SECTION OF THE CONVEYOR EQUIPMENT MANUFACTURERS ASSOCIATION (CEMA) It is the responsibility of the contractor, installer, owner and user to install, maintain and operate the conveyor, components and, conveyor assemblies in such a manner as to comply with the Occupational Safety and Health Act and with all state and local laws and
CEMA STANDARD NO: 352-2012 CEMA Safety Labels CEMA Document: SC 2004-01 The CEMA safety labels shown below should be used on screw conveyors, drag conveyors, and bucket elevators. Safety labels should be placed on inlets, discharges, troughs, covers, inspection doors & drive guards. See CEMA Safety Label Placement Guidelines on CEMA Web Site: http://www.cemanet.org Exposed moving parts can cause severe injury CHR930001 LOCK OUT POWER before removing guard http://www.cemanet.
CEMA STANDARD NO: 352-2012 CEMA Safety Labels Placement Guidelines Product: Bulk Handling Equipment Equipment: Screw Conveyor “C” “C” “C” To be placed on inlets and discharges, troughs, covers, and inspection doors of screw conveyors to provide warning against exposed moving parts while in operation.
CEMA STANDARD NO: 352-2012 CEMA Safety Labels Placement Guidelines Product: Bulk Handling Equipment Equipment: USE LABEL “A” ON BELT GUARD Vertical Screw Conveyor USE LABEL “B” ON ENDS OF TROUGH, ON INTAKE INSPECTION DOOR, AND BOTH SIDES OF DISCHARGE SPOUT "A" Exposed moving parts can cause severe injury BOTH SIDES LOCK OUT POWER before removing guard CHR930001 http://www.cemanet.
CEMA STANDARD NO: 352-2012 6.
CEMA STANDARD NO: 352-2012 SCREW CONVEYOR COMPONENTS Bill of Materials Item 7.
CEMA STANDARD NO: 352-2012 SECTION B - INSTALLATION RECEIVING 1. 2. 3. 4. Screw conveyors may be ordered as individual components with all the assembly operations performed in the field, or assembled completely by the manufacturer, with drawings and bill of materials. Immediately upon receipt all items in the shipment should be checked against shipping papers for shortages and inspected for damage. Items to be inspected include troughs, screws, covers and drive units.
CEMA STANDARD NO: 352-2012 17. Center hanger bearings between screw sections. Torque hanger assembly bolts to proper torque rating per Chart A. 18. Assemble seal and bearing to opposite trough end. Make sure end shaft is centered in seal and trough end openings. Torque bolts to proper torque rating per Chart A. 19. Insert end shaft through end bearing and into last screw section and install coupling bolts. DO NOT TIGHTEN COUPLING BOLTS. 20.
CEMA STANDARD NO: 352-2012 SECTION C - OPERATION BEFORE INITIAL START-UP: 1. 2. 3. 4. 5. 6. 7. LOCKOUT/TAGOUT ALL POWER. Lubricate all bearings in accordance with manufacturer's instructions. Lubricate all gear reducers in accordance with manufacturer's instructions. Gear reducers are normally shipped without lubrication. Check conveyor to ensure all tools and foreign materials have been removed. Turn drive unit by hand to check for alignment and obstructions.
CEMA STANDARD NO: 352-2012 SECTION D – MAINTENANCE Practice good housekeeping. Keep area around conveyor clean and free of obstacles to provide easy access and to avoid interference with the function of the conveyor. Establish routine periodic inspection of the entire conveyor to ensure continuous maximum operating performance. LOCKOUT/TAGOUT ALL POWER BEFORE INSPECTION OF CONVEYORS. Periodic inspections should be made of the following: • • • • • • • • • • Bearings – Check for proper lubrication.
CEMA STANDARD NO: 352-2012 SECTION E – SHUTDOWN AND STORAGE EMERGENCY SHUTDOWN An emergency shutdown may be necessary to clear obstructions or to replace damaged or worn components. 1. 2. 3. 4. 5. 6. 7. 8. LOCKOUT/TAGOUT ALL POWER. Remove all covers. Remove all obstructions and product from conveyor. Inspect all components for damage or wear. Check conveyor components in accordance with the Maintenance Section of this document. Replace all damaged or worn components.
CEMA STANDARD NO: 352-2012 SECTION F – TROUBLESHOOTING GUIDE PROBLEM CAUSE REMEDY FLIGHT THICKNESS TOO LIGHT INCREASE FLIGHT THICKNESS. USE ABRASION RESISTANT METERIALS OR HARDFACING RPM TOO HIGH OR TROUGH LOADING TOO HIGH REDUCE SPEED. CONSULT CEMA 350 BOOK TO DETERMINE RECOMMENDED SPEED AND TROUGH LOADING. INCORRECT ALIGNMENT REALIGN TROUGH ASSEMBLY AND HANGERS IN ACCORDANCE WITH ASSEMBLY SECTION OF THIS DOCUMENT.
CEMA STANDARD NO: 352-2012 SECTION F – TROUBLESHOOTING GUIDE - Continued PROBLEM CAUSE REMEDY MOTOR UNDERSIZED CONSULT CEMA 350 BOOK TO DETERMINE PROPER HORSEPOWER REQUIREMENTS. UPSET LOADING CONDITION EMPTY TROUGH, CONTROL FEED AND OPERATE UNDER DESIGN SPECIFICATIONS. BEARING CONTAMINATION UPGRADE OR REPLACE SEAL. CHANGE TO OUTBOARD BEARING. INSUFFICIENT LUBRICATION LUBRICATE IN ACCORDANCE WITH MAINTENANCE SECTION OF THIS DOCUMENT.
CEMA STANDARD NO: 352-2012 CHART A - BOLT TORQUE GUIDE GENERAL BOLT TIGHTENING TORQUE (Ft. lbs.) Bolt Dia.
CONVEYOR EQUIPMENT MANUFACTURERS ASSOCIATION 5672 Strand Court, Suite 2 Naples, Florida 34110-3314 Tel: 239-514-3441 http://www.cemanet.
