16 inch

Double-Sheave-J-Block

Key to two sheave J-Block Model Numbers

J 5 D 10 B T A
Shorty “J” Crane Block Safe Working Limit-Tons

Number of Sheaves

Double

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-20D16BTA 328 38.250 34.500 6.625 20.125 2.80 3.00 2.38
J-20D16BTB 484 38.250 34.500 10.062 20.125 2.80 3.00 2.38
J-20D16BTC 630 38.250 34.500 12.562 20.125 2.80 3.00 2.38
J-20D16RTA 328 38.250 34.500 6.625 20.125 2.80 3.00 2.38
J-20D16RTB 484 38.250 34.500 10.062 20.125 2.80 3.00 2.38
J-20D16RTC 630 38.250 34.500 12.562 20.125 2.80 3.00 2.38
J-25D16BTA 328 38.250 34.500 6.625 20.125 2.80 3.00 2.38
J-25D16BTB 484 38.250 34.500 10.062 20.125 2.80 3.00 2.38
J-25D16BTC 630 38.250 34.500 12.562 20.125 2.80 3.00 2.38
J-25D16RTA 328 38.250 34.500 6.625 20.125 2.80 3.00 2.38
J-25D16RTB 484 38.250 34.500 10.062 20.125 2.80 3.00 2.38
J-25D16RTC 630 38.250 34.500 12.562 20.125 2.80 3.00 2.38
J-30D16BTA 351 40.250 36.500 6.625 20.125 3.28 3.50 3.00
J-30D16BTB 506 40.250 36.500 10.062 20.125 3.28 3.50 3.00
J-30D16BTC 652 40.250 36.500 12.562 20.125 3.28 3.50 3.00
J-30D16RTA 351 40.250 36.500 6.625 20.125 3.28 3.50 3.00
J-30D16RTB 506 40.250 36.500 10.062 20.125 3.28 3.50 3.00
J-30D16RTC 652 40.250 36.500 12.562 20.125 3.28 3.50 3.00
J-35D16BTA 425 45 40.750 7.750 20.125 3.27 4.25 3.38
J-35D16BTB 581 45 40.750 11.187 20.125 3.27 4.25 3.38
J-35D16BTC 727 45 40.750 13.687 20.125 3.27 4.25 3.38
J-35D16RTA 425 45 40.750 7.750 20.125 3.27 4.25 3.38
J-35D16RTB 581 45 40.750 11.187 20.125 3.27 4.25 3.38
J-35D16RTC 727 45 40.750 13.687 20.125 3.27 4.25 3.38


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