12 inch

Five-Sheave-J-Block

Key to five sheave J-Block Model Numbers

J 25 QN 10 B T A
Shorty “J” Crane Block Safe Working Limit-Tons

Number of Sheaves

QN=5
Quintuple

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-25QN12BTA 345 34.750 27.750 13.500 16 2.80 3.00 2.38
J-25QN12BTB 466 34.750 27.750 17.062 16 2.80 3.00 2.38
J-25QN12BTC 618 34.750 27.750 21.560 16 2.80 3.00 2.38
J-25QN12RTA 345 34.750 27.750 13.500 16 2.80 3.00 2.38
J-25QN12RTB 466 34.750 27.750 17.062 16 2.80 3.00 2.38
J-25QN12RTC 618 34.750 27.750 21.560 16 2.80 3.00 2.38
J-30QN12BTA 373 39.125 31.250 13.500 16 3.28 3.50 3.00
J-30QN12BTB 495 39.125 31.250 17.062 16 3.28 3.50 3.00
J-30QN12BTC 647 39.125 31.250 21.562 16 3.28 3.50 3.00
J-30QN12RTA 373 39.125 31.250 13.500 16 3.28 3.50 3.00
J-30QN12RTB 495 39.125 31.250 17.062 16 3.28 3.50 3.00
J-30QN12RTC 647 39.125 31.250 21.562 16 3.28 3.50 3.00

*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