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Head Blocks, Underhung - 59 Series

Underhung Head Block
100-61259C25

Underhung style, normally supported by two structural I-beams.
ASTM Class 30 grey iron or nylon sheave.
Equal pitch diameter on rope and cable grooves for smooth operation.
Tapered roller bearings.
Base angle legs turned in to allow close mounting centers.
10 gauge side plates fully enclose sheave; 16" blocks have 7 gauge side plates.
Side plates are bolted and welded to the base angles for extra strength.
Six spacers between the side plates, three prevent cables from escaping the sheave grooves.
Base angles punched with alternating slots and holes for simple easy installations.
Mounting clips available, please provide steel dimensions.
Underhung blocks may need to be welded to head beams after final alignment. Clip angles are recommended for double beam mounting. Mounting with clips or to single beams will require welding. Consult the factory for specific information.
Head block capacities are affected significantly by mounting conditions, see the “More Info” tab for tables of capacities

Ordering Information

Sheave	Rope Diam.	Lines	Bearing	Cast Iron Prod. Code	Wt.	Nylon Prod. Code	Wt.	RWL (capacity)
Single Purchase
8"	3/4"	6 @ 1/4"	1"	100-60859C25	46 lb			table
8"	3/4"	8 @ 1/4"	1"	100-80859C25	52 lb			table
12"	3/4"	6 @ 1/4"	1"	100-61259C25	72 lb	100-61259N25	40 lb	table
12"	3/4"	8 @ 1/4"	1"	100-81259C25	79 lb	100-81259N25	41 lb	table
12"	3/4"	10 @ 1/4"	1"	100-101259C25	86 lb			table
16"	1"	6 @ 3/8"	1-1/2"	100-61659C381	139 lb			table
16"	1"	8 @ 3/8"	1-1/2"	100-81659C381	147 lb			table
Double Purchase
12"	3/4"	6 @ 1/4"	1"	1CD-61259R	72 lb	1ND-61259R	40 lb	table
12"	3/4"	8 @ 1/4"	1"	1CD-81259R	79 lb	1ND-81259R	41 lb	table

Wire Guide Blocks: Change the "R" suffix to "W" in the part number for blocks with tieoffs for arbor wire guides.

Tieoffs: Tieoffs for wire guided clews are also available.

RWL: The recommended working load (RWL) is maximum load that can be applied to a block which is in "like new" condition and has been properly installed, maintained and operated. The mounting of the head block has a major effect on the RWL, as shown in the tables. There are separate tables for beam angles, beam clips, and welding the block to the head beams.

Head Blocks, Underhung - 59 Series

Nominal Sheave Diam.	No. of Lines	DIM L	DIM H	DIM W	DIM A	DIM B	DIM D (Sheave DIM)
8"	6	32"	11-7/16"	5-3/8'	15-1/16"	2-3/16"	8-1/2"
8"	8	32"	11-7/16"	6-3/8"	15-1/16"	2-3/16"	8-1/2"
12"	6	34"	15"	5-3/8"	13-5/16"	2-3/16"	12"
12"	8	34"	15"	6-3/8"	13-5/16"	2-3/16"	12"
12"	10	34"	15"	7-1/4"	13-5/16"	2-3/16"	12"
16"	6*	34"	19"	6-5/8"	11-7/16"	2-3/16"	16"
16"	8*	34"	19"	7-3/8"	11-7/16"	2-3/16"	16"