10 inch

Four-Sheave-J-Block

Key to four sheave J-Block Model Numbers

J 15 Q 10 B T A
Shorty “J” Crane Block Safe Working Limit-Tons

Number of Sheaves

Q=4
Quadruple

Sheave Size – Nom. O.D.

Sheave Bearing:

B = Bronze Bushed
R= Roller Bearing

Hook-Thrust Bearing

Cheek Weights:
A = No wts.
AB = Med. wts.
B = Std. wts.
C = X-Heavy wts.


Model WT. A B E F H J K
Overall Net Thick- Width Throat Opening Hook Hook
Length Length ness w/ Latch Thick. Width
J-15Q10BTA 235 25.750 23.125 10.625 14 1.91 2.53 1.93
J-15Q10BTB 305 25.750 23.125 12.937 14 1.91 2.53 1.93
J-15Q10RTA 235 25.750 23.125 10.625 14 1.91 2.53 1.93
J-15Q10RTB 305 25.750 23.125 12.937 14 1.91 2.53 1.93
J-20Q10BTA 290 28 25 10.625 14 2.80 3.00 2.38
J-20Q10BTB 365 28 25 13.437 14 2.80 3.00 2.38
J-20Q10RTA 290 28 25 10.625 14 2.80 3.00 2.38
J-20Q10RTB 365 28 25 13.437 14 2.80 3.00 2.38
J-25Q10BTA 290 28 25 10.625 14 2.80 3.00 2.38
J-25Q10BTB 365 28 25 13.437 14 2.80 3.00 2.38
J-25Q10RTA 290 28 25 10.625 14 2.80 3.00 2.38
J-25Q10RTB 365 28 25 13.437 14 2.80 3.00 2.38
J-30Q10BTA 330 31.125 27.375 11.250 14 3.28 3.50 3.00
J-30Q10BTB 402 31.125 27.375 13.437 14 3.28 3.50 3.00
J-30Q10RTA 330 31.125 27.375 11.250 14 3.28 3.50 3.00
J-30Q10RTB 402 31.125 27.375 13.437 14 3.28 3.50 3.00


Dead End Chart

Wire Rope Size T U For Pin Size
7/16" thru 5/8" 1 1.28 1-1/4
3/4" thru 1" 1.25 1.65 1-5/8
1-1/8" thru 1-3/8" 1.75 2.51 2-1/2

*Gunnebo Johnson Design Factor is 4 to 1, with some exceptions;

45 Ton models 3.6 to 1

60 Ton models 3.7 to 1

325 Ton models 3.7 to 1