Alabama Administrative Code
Title 480 - ALABAMA DEPARTMENT OF LABOR
Chapter 480-3-3 - MINE SAFETY
Section 480-3-3-.08 - Hoisting Ropes (Steel Or Iron)
Current through Register Vol. 43, No. 02, November 27, 2024
(1) No rope for hoisting or lowering men shall be used when such hoisting or lowering is done by any means other than human or animal power, unless such rope shall be composed of metal wires with a factor of safety determined as hereinafter set forth; provided, however, that such metal wires may be laid around a hemp center. Such ropes shall be inspected daily.
(2) Safety Factor for Hoisting Ropes - The safety factor of a new rope shall be calculated by dividing the breaking strength of the rope as rated by the manufacturer, by the sum of the maximum load to be hoisted, plus the total weight of the rope in the shaft when fully let out.
Minimum
Minimum factor of
Length of rope factor of safety when
(vertical safety for rope must be or incline) new rope discarded
500 feet or less 8 6.4
500 to 1,000 feet 7 5.8
1,000 to 2,000 feet 6 5.0
2,000 to 3,000 feet 5 4.3
3,000 to more 4 3.6
(3) Shaft or Incline Rollers - The safety factor shall be calculated by dividing the breaking strength of rope (as rated by the manufacturer or in accordance with test of sample by the United States Bureau of Standards), by the maximum pull not including friction or acceleration-- that is, by the sum of the maximum weights to be hoisted including weight of skip or car and cage plus weight of material to be hoisted plus total weight of rope when extended to bottom of hoist way. If the hoist way is inclined, the calculated components of the weights parallel with the incline shall be used.
(4) Hoist Rope Maintenance - No rope shall be used for hoisting or lowering men (1) if there are six broken wires in one strand of a rope lay (2) if the wires on the crown are worn to sixty-five (65) per cent of their original diameter; (3) if more than three (3) wires which have been reduced by wear more than thirty (30) percent in cross-section are broken in one strand of rope lay (4) if marked corrosion appears (5) if minimum safety factor falls below that specified in these rules. Where it is not practical to caliper accurately rope strands of wire in the field, then the test for wear and remaining strength shall be determined by measuring across the crown of the wire in accordance with methods approved by the Department.
(Follow manufacturer's recommendations for other kinds of wire rope).
Diameter Space of rope (inches) Number of clips between clips (inches)
3/4 5 4-1/2
7/8 5 4-1/4
1 5 6
1-1/8 5 7
1-1/4 6 8
1-3/8 7 9
1-1/2 8 10
1-5/8 8 10
1-3/4 8 11
1-7/8 8 12
2 8 12
(5) Hoist Rope Reports - In a book in the mine office the operator shall keep a record of every hoisting rope used for hoisting and lowering men, noting the length and cross-sectional dimensions of the rope, the breaking strength of the rope as given by the manufacturers, the name and address of the maker, the date of purchase, the date when put in use, the designation of the shaft and compartment or slope in which the rope is used, the dates of resocketing, re-clamping, and shortening, the length of rope cut off at each such operation, the dates of reversing ends, the date when discarded, the reason for discarding, and other items which appear to him to be pertinent to safe and efficient use of hoist rope.
(6) Lubrication of Hoist Ropes - Every hoisting rope used in shafts shall be lubricated at least twice monthly with a suitable lubricant. Only lubricants recommended by the rope manufacturer and developed as the result of tests shall be used.
Author: Marcus Davis, Workers' Compensation Examiner.
Statutory Authority: Code of Ala. 1975, § 25-2-13(2).