LIFTINGSAFETY
Yoke 541 Series Forged Snatch Block with Shackle - 12 or 15 tonnes

Yoke 541 Series Forged Snatch Block with Shackle - 12 or 15 tonnes

Forged pulley block fitted with a bow shackle and built in RFID chip. To suit wire line sizes between 19 and 22mm.

Model: 

8-541-xx / YFSB-5521

Yoke 541 Series Forged Snatch Block with Shackle - 12 or 15 tonnes

8-541 Series Snatch Block

Features

  • YOKE Forged Snatch Blocks are manufactured of the highest quality forged alloy steel.
  • Available from 12 tonnes to 15 tonnes, for wire rope sizes 19mm to 22mm.
  • Certified by ABS Type Approval.
  • Part number, wire rope size and working load limit are marked on each block.
  • Permanent batch codes link to test certificates for easy
  • Supplied with bronze bushings and pressure lube fittings.
  • Meets or exceeds all requirements of ASME B30.26.
  • Safety factor 4:1
  • Fatigue rated
  • Supplied with a Certificate of Conformity
  • Factory fitted with an RFID chip for serial and certificate traceability.
  • Sheave groove bottom is hardened to 35 Rc to maximise durability.
  • Closed die forged steel sheave

Specifications

Item No. Sheave Dia. (inch) Bearing Type Wire Rope Dia. (mm) Working Load Limit (tonnes)* Weight (lbs) Weight (kg)
8-541-12 6 Bronze Bushing 19-22 12 52 24
8-541-15 8 Bronze Bushing 19-22 15 61 28
8-541-1510 10 Bronze Bushing 19-22 15 90 41

*Minimum Ultimate Load is 4 times the Working Load Limit.

Dimensions

Item No. B (mm) E (mm) F (mm) G (mm) L (mm) R (mm) T (mm)
8-541-12 80 141 44 166 540 496 44
8-541-15 80 141 44 220 589 545 44
8-541-1510 80 141 44 280 714 670 44
Dimensional Drawing

Loads on Blocks

Angle Factor Multipliers

The Working Load Limit (WLL) for Yoke Group blocks indicates the maximum load that should be exerted on the block and its connecting fitting. This total load value may be different from the weight being lifted or pulled by a hoisting system. It is necessary to determine the total load being imposed on each block in the system to properly determine the rated capacity block to be used. A single sheave block used to change load line direction can be subjected to total loads greatly different from the weight being lifted or pulled. The total load value varies with the angle between the incoming and departing lines to the block.

The following chart indicates the factor to be multiplied by the line pull to obtain the total load on the block.

Angle Factor
Angle Factor Angle Factor
0 2 100 1.29
10 1.99 110 1.15
20 1.97 120 1
30 1.93 130 0.84
40 1.87 135 0.76
45 1.84 140 0.68
50 1.81 150 0.52
60 1.73 160 0.35
70 1.64 170 0.17
80 1.53 180 0
90 1.41 - -

Sheave Size and Wire Rope Strength

Ratio A Strength Efficiency Compared to Catalogue Strength in % Ratio A Strength Efficiency Compared to Catalogue Strength in %
40 95 8 83
30 93 6 79
20 91 4 75
15 89 2 65
10 86 1 50

Strength Efficiency

Bending wire rope reduces its strength. To account for the effect of bend radius on wire rope strength when selecting a sheave, use the table above.

Ratio B Relative Fatigue Bending Life Ratio B Relative Fatigue Bending Life
30 10 16 2.1
25 6.6 14 1.5
20 3.8 12 1.1
18 2.9 - -
Part N° Sheave Dia. (inch) Bearing Type Wire Rope Dia. (mm) Working Load Limit (tonnes)* Weight (kg) Unit Price Quantity
5521-T28466 6 Bronze Bushing 19-22 12 24 £  840.00
5521-T28467 8 Bronze Bushing 19-22 15 28 £  975.00
5521-T28468 10 Bronze Bushing 19-22 15 41 £  1150.00
   

Features

  • YOKE Forged Snatch Blocks are manufactured of the highest quality forged alloy steel.
  • Available from 12 tonnes to 15 tonnes, for wire rope sizes 19mm to 22mm.
  • Certified by ABS Type Approval.
  • Part number, wire rope size and working load limit are marked on each block.
  • Permanent batch codes link to test certificates for easy
  • Supplied with bronze bushings and pressure lube fittings.
  • Meets or exceeds all requirements of ASME B30.26.
  • Safety factor 4:1
  • Fatigue rated
  • Supplied with a Certificate of Conformity
  • Factory fitted with an RFID chip for serial and certificate traceability.
  • Sheave groove bottom is hardened to 35 Rc to maximise durability.
  • Closed die forged steel sheave

Specifications

Item No. Sheave Dia. (inch) Bearing Type Wire Rope Dia. (mm) Working Load Limit (tonnes)* Weight (lbs) Weight (kg)
8-541-12 6 Bronze Bushing 19-22 12 52 24
8-541-15 8 Bronze Bushing 19-22 15 61 28
8-541-1510 10 Bronze Bushing 19-22 15 90 41

*Minimum Ultimate Load is 4 times the Working Load Limit.

Dimensions

Item No. B (mm) E (mm) F (mm) G (mm) L (mm) R (mm) T (mm)
8-541-12 80 141 44 166 540 496 44
8-541-15 80 141 44 220 589 545 44
8-541-1510 80 141 44 280 714 670 44
Dimensional Drawing

Loads on Blocks

Angle Factor Multipliers

The Working Load Limit (WLL) for Yoke Group blocks indicates the maximum load that should be exerted on the block and its connecting fitting. This total load value may be different from the weight being lifted or pulled by a hoisting system. It is necessary to determine the total load being imposed on each block in the system to properly determine the rated capacity block to be used. A single sheave block used to change load line direction can be subjected to total loads greatly different from the weight being lifted or pulled. The total load value varies with the angle between the incoming and departing lines to the block.

The following chart indicates the factor to be multiplied by the line pull to obtain the total load on the block.

Angle Factor
Angle Factor Angle Factor
0 2 100 1.29
10 1.99 110 1.15
20 1.97 120 1
30 1.93 130 0.84
40 1.87 135 0.76
45 1.84 140 0.68
50 1.81 150 0.52
60 1.73 160 0.35
70 1.64 170 0.17
80 1.53 180 0
90 1.41 - -

Sheave Size and Wire Rope Strength

Ratio A Strength Efficiency Compared to Catalogue Strength in % Ratio A Strength Efficiency Compared to Catalogue Strength in %
40 95 8 83
30 93 6 79
20 91 4 75
15 89 2 65
10 86 1 50

Strength Efficiency

Bending wire rope reduces its strength. To account for the effect of bend radius on wire rope strength when selecting a sheave, use the table above.

Ratio B Relative Fatigue Bending Life Ratio B Relative Fatigue Bending Life
30 10 16 2.1
25 6.6 14 1.5
20 3.8 12 1.1
18 2.9 - -

Contact Us About This Product

LiftingSafety uses cookies to improve your user experience,
To accept this, please click the 'accept' button below.

Find out more