Main features: 

The hook is manly composed of elevator bail, elevator bail seat, barrel, hook body, hook rod and spring etc. In the barrel there are inner and outer springs which can make the pin of standpipe spring up backwards. 

On the top of the barrel there is a safety positioning device. When lifting an empty elevator, the positioning device can stop the rotation of the hook body; when lifting a elevator with drill string, the positioning device no longer can stop the rotation of the hook body; the hook body can rotate freely. 

The detent device can lock hook body at any one of eight even positions. 

And the safety pin body of the hook can also be locked by locking deice. 

For protecting DP connector while breaking out, there is a hydraulic buffer device installed in the hook. 

A reliable safety device is installed at hook opening. 

The main load-bearing parts have been inspected by NDT completely. 

Main technical parameters :

Model	DG90	DG135	DG170	DG225	DG315	DG450	DG585
Max. hook load kN	900	1350	1700	2250	3150	4500	5850
Opening size of main hook mm(in)	155(6 1/16)	165  (6 1/2)	180  (7)	190 (7 1/2)	220 (8 5/8)	220  (8 5/8)	238 (9 3/8)
Main hook DN mm(in)	116  (4 1/2)	140  (5 1/2)	150  (6)	160  (6 1/4)	180  (7)	180  (7)	180  (7)
Auxiliary hook DN mm(in)	80 (3 1/8)	90 (3 1/2)	90 (3 1/2)	100 (4)	120  (4 3/4)	120  (4 3/4)	120  (4 3/4)
Spring trip mm(in)	180 (7)	180 (7)	180 (7)	180 (7)	200 (8)	200 (8)	200 (8)
Dimensions (L×W×H) mm	2000×680 ×600	2200×720 ×616	2450×750 ×630	2545×780 ×750	2953×890 ×830	2950×890 ×880	3156×930 ×930