Design features of substructure

The types of substructure are divided into four kinds as slingshot (dually raised- type), swing up, block package and box-on-box.
Structural features of slingshot substructure
●The drill floor and the equipments on it can be installed at low position; and the mast is erected up to vertical position while the drill floor keeps low-position, then the drill floor and the mast are lifted integrally to working position. 

●There are two hydraulic cylinders equipped on top layer of the substructure; they can be used for buffering and regulating while lifting the drill floor, and as a pushing force while laying down the drill floor. 

●It is designed into modules. For land way and railway transportation, the substructure can be disassembled into small pieces and also into large pieces for oil field transportation as well. 

●There is standby interface at the bottom layer of the substructure for integral trailer or horizontally moving device; the mast, drawworks and BOP device etc can be moved integrally. It meets the requirement of quick movement and drilling cluster well. 

The structural features of swing up substructure 
●Parallelogram lifting structure is used, so drill floor and the equipments on it can be installed at low position, and lifted by the drawworks force. 

●There are two hydraulic cylinders equipped on top layer of the substructure; they can be used for buffering and regulating while lifting the drill floor, and as a pushing force while laying down the drill floor. 
●Less power is needed and stable for lifting. 

The features of block package substructure

●The structural type is “tall front and low back” . The front of the substructure is taller, meeting the requirement of standard BOP installation. The back of the substructure is lower, meeting the installation requirement of heavier power equipment and drive device. 

●The main parts are big components with good rigidness, so they are stable. 
The features of box-on-box substructure
●The main structure is big box-on-box structure, the location between each layers is fixed by combination of concave and convex blocks. 

●It is simple, quick and stable for its installation.

Technical parameters1：

Type	Swing up type		Box-on-box Type	Slingshot type		Block package Type
Model	DZ158/6-S	DZ180/6-S	DZ170/8.6-XD	DZ225/7.5-G	DZ315/9-G	DZ225/7.5-K
Drill floor height (M)	6	6	8.6	7.5	9	7.5
Clear height under RT beam(M)	4.3	4.3	7.223	6.26	7.62	6.32
RT beam load(kN )	1580	1800	1700	2250	3150	2250
Setback load (kN )	870	1080	1080	1125	1800	1440
Mast bottom span (M)	/	/	7.5	8	8	8