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Multi-cycle circulatings subs SDT-CS

General Description
General Description Features & Benefits Specifications Related Resources
Significantly increases economical efficiency by reducing time per operation
Restore circulation, bottom hole chemical treatments are possible without BHA additional tripping
Up to 10 activations at one BHA trip (4/5 activations is standard)
In case of circulation stop, the sub blocks the ports automatically to prevent cross flow of mud between annular space and the drill string
Simple visual control of pressure drop
No limitations for LCM type of materials to deal with loss of circulation
Operation over a wide range of specific weight of fluids and wells TVD by adjusting the deactivating pressure (2100psi, 3000psi, 4500psi)
The «dump sub» function can be activated after pulling out of hole
The spline drive and latch mechanism are enclosed in a single, sealed oil chamber without ports to the annulus. Such ports on other jars may fill with cuttings and restrict the down jar stroke.
Sub can operate in the harshest environments including CO2 and H2S
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General Description
The Circulating subs is used for diverting the mud flow inside the drill string to the annulus whenever required and combat common drilling problems, such as lost circulation and limited circulation rates.

The sub operation mode is adjusted from the surface by balls dropping without need for tripping.

The sub has several configurations, which differ by number of operation cycles and activation/deactivation pressures without need of pulling out of hole. There is no need for presence of specific operational engineer at the rig.

It is always recommended to include the circulation sub into BHA in following cases:
Acid, chemical and bridging agents (LCM) treatments, which can be harmful for below located BHA components;
Reaming during loss of circulation, full loss of circulation; wellbore cleanout required for acceleration of the flow in annular space by increase of mud flow.
Filling and emptying the inner tube space of the drill pipe during pulling and running operations (bypass valve function);
Cut-off of the underlying assembly from the ingress of the scale and hardener drilling mud during extension of the drill string
The sub has several configurations, which differ by number of operation cycles and activation/deactivation pressures without need of pulling out of hole. There is no need for presence of specific operational engineer at the rig.
Features & Benefits
Significantly increases economical efficiency by reducing time per operation
Restore circulation, bottom hole chemical treatments are possible without BHA additional tripping
Up to 10 activations at one BHA trip (4/5 activations is standard)
In case of circulation stop, the sub blocks the ports automatically to prevent cross flow of mud between annular space and the drill string
Simple visual control of pressure drop
No limitations for LCM type of materials to deal with loss of circulation
Operation over a wide range of specific weight of fluids and wells TVD by adjusting the deactivating pressure (2100psi, 3000psi, 4500psi)
The «dump sub» function can be activated after pulling out of hole
The spline drive and latch mechanism are enclosed in a single, sealed oil chamber without ports to the annulus. Such ports on other jars may fill with cuttings and restrict the down jar stroke.
Sub can operate in the harshest environments including CO2 and H2S
Specifications
Imperial SDT-CS415 SDT-CS475 SDT-CS500 SDT-CS600 SDT-CS675 SDT-CS825 SDT-CS900 SDT-CS950
Basic Parameters and Dimensions                
Tool size, in 4 ⅙ 4 ¾ 5 6 ⅛ 6 ¾ 8 ¼ 9 9 ½
Length (C), in 75.0 95.0 84.3 128.9 105.3 115.9 124.5 119.9
Weight, lb 196 315 331 710 794 1 124 1 488 1 477
Number of ports 2 2 2 2 2 2 2 2
Port size, in 0.57 1.02 1.02 1.02 1.02 1.24 1.24 1.24
Number of activation balls 1 1 1 1 1 1 1 1
Number of deactivation balls 2 2 2 2 2 2 2 2
Tool connections (Top&Bottom) 3 ½ FH (NC-31) 3 ⅞ FH (NC-38) 3 ⅞ FH (NC-38) 4 ½ FH (NC-46) 4 ½ FH (NC-46) 6 ⅝ Reg 7 ⅝ FH 7 ⅝ Reg
Tool mid connection 3 ½ FH (NC-31) 3 ⅞ FH (NC-38) 3 ⅞ FH (NC-38) 4 ½ FH (NC-46) 4 ½ FH (NC-46) 6 ⅝ Reg 7 ⅝ FH 7 ⅝ Reg
Operating Parameters                
Maximum flow rate, gpm 238 396 396 713 713 1014 1014 1014
Pressure drop with direct circulation (with empty basket) , psi 116 61 61 116 116 73 73 73
Pressure drop (circulation through side ports), psi 174 54 54 218 218 174 174 174
Number of cycles (std / ext) 5/10* 5/10* 5/10* 5/10* 5/10* 5/10* 5/10* 5/10*
Activation pressure, psi 58 87 87 87 87 58 58 58
Deactivation pressure, psi 2 100 2 100 2 100 2 100 2 100 2 100 2 100 2 100
Blocking ball push-through pressure, psi 1 088 1 088 1 088 1 088 1 088 1 088 1 088 1 088
Maximum tensile load, lb 512 500 737 250 860 000 778 700 1 344 300 2 135 500 2 337 500 2 810 000
Torsional strength main body, ft·lb 15 860 18 880 27 430 37 615 55 900 106 200 125 400 147 500
Metric SDT-CS415 SDT-CS475 SDT-CS500 SDT-CS600 SDT-CS675 SDT-CS825 SDT-CS900 SDT-CS950
Basic Parameters and Dimensions                
Tool size, mm 106 120 127 155 172 210 229 240
Length (C), mm 1 906 2 412 2 140 3 275 2 674 2 945 3 162 3 045
Weight, kg 89 143 150 322 360 510 675 670
Number of ports 2 2 2 2 2 2 2 2
Port size, mm 14.5 25.8 25.8 25.8 25.8 31.5 31.5 31.5
Number of activation balls 1 1 1 1 1 1 1 1
Number of deactivation balls 2 2 2 2 2 2 2 2
Tool connections (Top&Bottom) 3 ½ FH (NC-31) 3 ⅞ FH (NC-38) 3 ⅞ FH (NC-38) 4 ½ FH (NC-46) 4 ½ FH (NC-46) 6 ⅝ Reg 7 ⅝ FH 7 ⅝ Reg
Tool mid connection 3 ½ FH (NC-31) 3 ⅞ FH (NC-38) 3 ⅞ FH (NC-38) 4 ½ FH (NC-46) 4 ½ FH (NC-46) 6 ⅝ Reg 7 ⅝ FH 7 ⅝ Reg
Operating Parameters                
Maximum flow rate, l/min 900 1 500 1 500 2 700 2 700 3 840 3 840 3 840
Pressure drop with direct circulation (with empty basket), MPa 0.8 0.42 0.42 0.8 0.8 0.5 0.5 0.5
Pressure drop (circulation through side ports), MPa 1.2 0.37 0.37 1.5 1.5 1.2 1.2 1.2
Number of cycles (std / ext) 5/10* 5/10* 5/10* 5/10* 5/10* 5/10* 5/10* 5/10*
Activation pressure, MPa 0.4 0.6 0.6 0.6 0.6 0.4 0.4 0.4
Deactivation pressure, MPa 14.5 14.5 14.5 14.5 14.5 14.5 14.5 14.5
Blocking ball push-through pressure, MPa 7.5 7.5 7.5 7.5 7.5 7.5 7.5 7.5
Maximum tensile load, kN 2 280 3 280 3 825 3 464 5 980 9 500 10 400 12 500
Torsional strength main body, kN·m 21.5 25.6 37.2 51 75.8 144 170 200
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