Four Sheave Hoisting Tackle 200KN Load Block and Tackle for Tower Erection Reeving

A four sheave tackle is a reeving decision before it is a hardware purchase. With four sheaves and the rope led correctly, the pull on the lead line drops to roughly a quarter of the load, which is what lets a small winch lift a tower section that no single sheave block would move. This QH series casting steel tackle covers one to four sheaves from 10KN to 200KN, with the QH20-4 rated 200KN on 205mm cast steel wheels for rope up to 18mm.

Item No.	Model	Sheaves	Rated Load (kN)	Sheave (mm)	Max Rope (mm)	Weight (kg)
11181	QH1x1	1	10	100 x 31	8	3
11211	QH5x1	1	50	166 x 40	15.5	9
11231	QH10x1	1	100	246 x 60	19	22
11244	QH15-4	4	150	150 x 39	11	28
11245	QH20-1	1	200	305 x 68	23	56
11248	QH20-4	4	200	205 x 50	18	50

All wheels are cast steel on sealed bearings in a galvanized frame, with hanger available as hook, plate or ring; the hanger type must be stated on the order because it changes the head fitting.

A tackle with n sheaves supporting the load gives a theoretical advantage of n and an actual advantage of about n x 0.96 to the power n, allowing for bearing and rope friction. In practice: one sheave gives about 0.96 of the load on the lead line, two sheaves 0.92, three 0.88, and four 0.85. That is why a four sheave 200KN tackle can be worked with a lead line load near 47KN rather than 200KN, and why the anchor point on the tower has to be rated for the same lead line load plus the load carried by the becket.

Keep the sheave diameter at least ten times the rope diameter, and fifteen times for a rope that runs continuously. The QH20-4 with 205mm wheels suits 18mm rope at the ten times rule; running a 23mm rope on it would bend the strands tighter than the rope is designed for and shorten its life. Groove radius should match the rope, not the cable, and a groove worn wide by a previous rope is a reason to change the sheave, not to keep using it.

Keep the fleet angle into the lead sheave under about four degrees, or the rope will rub the groove side wall and the sheave will wear a taper. Anchor the fixed block on the structure axis so the load does not pull the tower leg out of plumb, use a shackle rather than a hook at any point that will be shock loaded, and never let the rope cross itself inside the frame. On tower erection work, check the head plate orientation before lifting: a plate hanger fitted the wrong way round side loads the frame.

Check the groove for rope wear, spin each sheave and listen for bearing noise, inspect the hanger and head fitting for elongation, and check that the frame is not twisted after any side pull. Sheaves and bearings are replaceable parts; a tackle with a scored groove should be re-wheeled before it goes back on a lift.

Packed in wooden cases, 1 piece per case for units above 20kg. Monthly capacity around 1000 pieces, delivery 7 to 15 days, minimum order 1 piece, OEM marking and packing marks to the buyer drawing.

Can the four sheave unit be re-reeved for two falls? Yes, use only two of the sheaves and lead the rope through them, but confirm the rope size against the sheave diameter.

Which hanger suits a lifting lug? Plate hanger with a shackle; hook hangers are for quick attachment, not for permanent lifting points.

Is a nylon wheel version available for live line work? Yes, insulated and nylon wheel hoisting tackles are a separate product line.