California Code of Regulations › Title 8 - Industrial Relations › Division 1 - Department of Industrial Relations › Chapter 4 - Division of Industrial Safety › Subchapter 20 - Tunnel Safety Orders › Article 19 - Shafts and Hoisting Systems › Section 8497 - Wire Rope and Sheaves

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a)
					 Factor of Safety. All rope to be used for regular hoisting shall be wire rope
					 providing a factor of safety not less than five to one for material hoist and
					 ten to one for personnel hoist when new, which shall be calculated by dividing
					 the breaking strength of the wire rope as given in the manufacturer's published
					 tables, by the total load to be hoisted including the total weight of the wire
					 rope in the shaft when fully let out, plus a proper allowance for impact and
					 acceleration.
The acceleration allowance shall be in accordance with
						manufacturer's recommendations, but in all cases the factor of safety of five
						or more must be maintained when the load, used in determining it, is greater
						than the actual weight by a percentage that is numerically three times the
						acceleration or deceleration, whichever is greatest. For example, a
						deceleration or acceleration of two feet per second that increases the load
						would require use of an effective load 6 percent greater than the actual
						weight, in the calculation of a factor of safety.
(b) Wire Rope Fastenings. Every wire rope
					 used for hoisting shall be securely fastened at both ends and when in use shall
					 not be fully unwound; at least three full turns shall remain on the drum so as
					 to protect the end fastening at drum from overload. The wire rope end at the
					 cage, skip or bucket shall be securely fastened by a properly made tapered
					 socket joint, by an eye in the wire rope made with an oval thimble and wire
					 rope clips, or by another method acceptable to the Division for this or similar
					 service. If the wire rope clip method is used, the spacing and number used
					 shall be as shown in Table - 1 for U-Bolts and in Table - 2 for Fist-Grip clips
					 based upon using RRL or RLL wire rope, 6 x 19 or 6 x 37 Class, FC or IWRC; IPS
					 or XIP. If Seale construction or similar large outer wire type construction in
					 the 6 x 19 Class is to be used for sizes 1 inch and larger, add one additional
					 clip. If a pulley (sheave) is used for turning back the wire rope, add one
					 additional clip.
The number of clips shown also applies to
						rotation-resistant RRL wire rope, 8 x 19 Class, IPS, XIP, sizes 1- ½
						inch and smaller; and to rotation-resistant RRL wire rope, 19 x 7 Class, IPS,
						XIP (sizes 1- ¾ inch and smaller for U-Bolts and size 1- ½ inch
						and smaller for Fist Grips).
NOTE: Wire rope abbreviation used above --
RRL
--
Right Regular Lay
Rll
--
Right Lange Lay
FC
--
Fiber Rope Core
IWRC
--
Independent Wire Rope
								Core
IPS
--
Improved Plow Steel
XIP
--
Extra Improved Plow
								Steel
Table 1 - Manufacturer's Recommendation for Using
						U-Bolt with Thimble Terminations
Clip
								  Size* Inches
Min. No. of
								  Clips
Amount of Rope to Turn
								  Back -- Inches
Torque in Lbs.
								  Ft.
½
3
11- ½
65
9/16
3
12
95
5/8
3
12
95
¾
4
18
130
7/8
4
19
225
1
5
26
225
1- 1/8
6
34
225
1- ¼
6
37
360
1- 3/8
7
44
360
1- ½
7
48
360
1- 5/8
7
51
430
1/34
7
53
590
2
8
71
750
2- ¼
8
73
750
* Same as nominal rope diameter.
If a greater number of clips used than shown in the
						table, the amount of rope turnback should be increased proportionately. ABOVE
						BASED ON USE OF CLIPS ON NEW ROPE.
Manufacturer's recommendations shall be followed for
						other kinds of wire ropes.
Table 2 - Manufacturer's Recommendation for Using
						Fist Clips with Thimble Terminations.
Clip
								  Size* Inches
Min. No. of
								  Clips
Amount of Rope to Turn
								  Back -- Inches
Torque in Lbs.
								  Ft.
½
3
11
65
9/16
3
12- ¾
130
5/8
3
13- ½
130
¾
4
16
225
7/8
4
26
225
1
5
37
225
1- 1/8
5
41
360
1- ¼
6
55
360
1- 3/8
6
62
500
1- ½
7
78
500
If a greater number of clips are used than shown in the
						table, the amount of turnback should be increased proportionately.
* The tightening torque values
						shown are based upon the threads being clean, dry, and free of
						lubrication.
(c) Unsafe Wire
					 Rope. No wire rope shall be used for hoisting when:
(1) There are 6 broken wires in one rope lay
					 or 3 broken wires in one strand of a rope lay, or
(2) Wires on the crown are worn to 65 percent
					 of their original diameter, or
(3)
					 Kinking, birdcaging, high stranding, displacement or distortion of the rope
					 structure exists, or
(4) Heat
					 damage or marked corrosion exists, or
(5) Conditions exist which exceed the wire
					 rope manufacturer's removal criteria.
(6) Loss of more than ten percent of rope
					 strength as determined by nondestructive testing.