Hook Type Single Sheave Stringing Block for 10kV and 35kV
Distribution Work
Distribution stringing is not a scaled down transmission job. Crews
hang twenty to forty blocks in a morning, often from a bucket or a
pole ladder, and the block has to go on and come off with one hand.
This hook type single sheave block covers 5KN to 20KN on sheaves
from 120mm to 250mm, weighs 1.5kg to 4.6kg, and takes LGJ 25
through LGJ 240 conductor. The hook open mouth clears a standard
crossarm bolt, so no separate plate and no second spanner.
Model Code and Nylon Series Data
The model code reads outer sheave diameter x sheave width in
millimetres, so SHDN-200*60 is a 200mm sheave with a 60mm wide
groove. Nylon sheave versions of the six most used sizes:
| Item No. | Model | Suitable Conductor | Rated Load (kN) | Weight (kg) |
| 10191 | SHDN-120*30 | LGJ 25-70 | 5 | 1.5 |
| 10192 | SHDN-160*40 | LGJ 95-120 | 10 | 2.5 |
| 10193 | SHDN-200*40 | LGJ 150-240 | 15 | 3.6 |
| 10194 | SHDN-200*60 | LGJ 150-240 | 15 | 4.0 |
| 10195 | SHDN-250*40 | LGJ 150-240 | 20 | 4.0 |
| 10196 | SHDN-250*60 | LGJ 300-400 | 20 | 4.5 |
Aluminium sheave versions are available at the same sizes and carry
the same rated loads; the nylon build is 0.4kg to 1.5kg lighter and
does not mark aluminium strands. Larger sizes run to SHDN-400*120
at 20KN for LGJ 400-500.
Choosing Between Hook and Plate Hanger
Hook type: fastest to hang on a bolt or a hook bracket, one hand operation,
no loose parts. Use it where the block goes up and down repeatedly
on the same structure.
Plate type: bolts through the crossarm and stays put. Use it where a block
remains in position for the whole pull, or where the hanger has to
take a side load at an angle structure.
Both are single sheave: splicing sleeves, steel wire rope and connectors pass through the
groove, which matters when a joint has to run through the block
during the pull.
Matching Sheave to Conductor
Do not choose by rated load alone. The sheave diameter sets the
bend radius the conductor sees, so pick from the conductor range in
the table and only then check the load figure against the pull per
conductor. A 5KN block on LGJ 240 will hold the load but will bend
the conductor tighter than the strand layer likes. Groove width
should be a few millimetres wider than the conductor diameter, and
the groove radius should sit on the conductor, not on the splice
sleeve.
Field Checks Before Each Pull
Check that the hook throat is not worn, the keeper closes fully and
the latch spring returns, the sheave spins freely with no grit in
the bearing, and the groove has no burr from a previous splice. A
block that has dropped on concrete usually shows a flat spot on the
sheave rim, which will mark the conductor on the next pull.
Packing and Supply
Blocks are packed in wooden cases, 20 to 40 pieces per case
depending on size, with the goods protected against movement in
transit. Monthly capacity is around 1000 pieces, delivery 7 to 15
days, minimum order 1 set, and OEM marking and packing marks can
follow the buyer drawing. Spare sheaves and keeper pins are
supplied as service parts.
Frequently Asked Questions
Can one block take both hook and plate hanger? The hanger is fixed
at build; order the version you need, or order both versions for a
mixed fleet.
Is the nylon sheave replaceable? Yes, the sheave and bearing swap
as a unit and are stocked as spares.
Which size suits ACSR 120mm2? SHDN-160*40 is the usual choice,
rated 10KN for LGJ 95-120.
