Mastergear Manual declutchable Gearboxes:

MASTERGEAR manual declutchable gearboxes are used for the manual operation of 90° shut-off valves mounted on a pneumatic, hydraulic actuator. The gearboxes have a cover flange and can therefore be mounted between the valve and the pneumatic or hydraulic actuator. At the moment are available three different principles applicated for this purpose.

Worm declutchable override gearboxes series „SD“
Top pull declutchable gearboxes series „P declutch“.
Side declutchable gearboxes series „SDT.

Manual Override Gearboxes Series SD:

MASTERGEAR manual override gearboxes design “Worm Declutch” are used for the manual operation of 90° shut-off valves mounted on a pneumatic actuator The wormshaft is disengaged from the quadrant teeth during normal operation. The quadrant transmits the rotary motion of the actuator via a coupling onto the valve shaft. For manual operation, the worm is swiveled into the quadrant teeth by means of a lever and then fixed. Now the valve and the pneumatic actuator can be operated via the gearbox. When used with single-acting actuators, it is necessary to operate against the spring load of the actuator. All gearboxes are self-locking so that any chosen position can be driven to and maintained. In order to prevent the pneumatic actuator from being actuated by pressure during the manual override operation, the actuator must be equipped with a safety locking system and/or a shut-off valve must be mounted onto the gearbox. The shut-off valve (3/2-qay valve) is automatically activated as soon as the lever for clutching or declutching the worm shaft is operated. Once the lever has been operated, the pneumatic actuator is vented and simultaneously the inlet air pressure is cut off. The position is maintained until the wormshaft is declutched. Take into account the max. spring force of the actuator and the max. output torque of the valve together as a magnitude when selecting the gearbox for single-acting actuators. Suitable couplings can be supplied for the power transmission between the actuator and the valve or the quadrant in the gearbox, if requested.

Materials:

Part. No.	Description	SLO39 -40°C / +80°C Standard	SLO20 -60°C / +80°C Not shock proof	SL120 -60°C / +80°C Shock proof
1.	Eccentric Bush short	Steel	Steel	Steel
2.	Aligning Rod	Steel	Steel	Steel
3.	Aligning Rod	Steel	Steel	Steel
4.	Thrust Washer	Needle thrust washer	Needle thrust washer	Needle thrust washer
5.	Thrust bearing	Needle thrust bearing	Needle thrust bearing	Needle thrust bearing
6.	“ O” Ring	NBR	PTFE	PTFE
7.	Eccentric Bush long	Steel	Steel	Steel
8.	Input seal plate	Steel	Steel	Steel
9.	Handel	Plastic	Steel	Steel
10.	Dowel Pin	Hardened + ground steel	Hardened + ground steel	Hardened + ground steel
11.	Soc. Cup Screw	Steel	Stainless steel	Stainless steel
12.	Wormshaft	Treated steel	Treated steel	Treated steel
13.	“ O” ring	NBR	PTFE	PTFE
16.	Wormshaft bushing	Sintered iron cooper	Sintered iron cooper	Sintered iron cooper
17.	Quadrant	S.G. cast iron	S.G. cast iron	S.G. cast iron
18.	Gearcase	Cast iron	S.G. cast iron	Low temperature steel
19.	Stop screws	Steel	Stainless steel	Stainless steel
20.	“ O” Ring	NBR	PTFE	PTFE
21.	Stop screws cup	Plastic	Plastic	Plastic
22.	Top flange	S.G. cast iron	S.G. cast iron	Low temperature steel
23.	Lock-Screw	Steel	Stainless steel	Stainless steel
26.	Hex. Head Screw	Steel	Stainless steel	Stainless steel
27.	Lever Rod	Steel	Steel	Steel

Description	MO7SD	M10SD	M12SD	M14SD	M15SD
MAX OUTPUT TORQUE (Nm)	338	678	1355	2190	4076
MAX INPUT TORQUE (Nm)	37	45	98	110	180
Ratio	51:1	55:1	50:1	72:1	84:1
MECHANICAL ADVANTAGE	9	15,1	13,8	19,8	22,7
VALVE MOUTING FLANGE ISO	F05/07	F07/F10	F10/F12/F14	F12/F14/F16	F14/F16/F20
ACTUATOR VALVE MOUTING FLANGE ISO	F05/07	F07/F10	F10/F12/F14	F12/F14/F16	F12/F14/F16
VALVE SHAFT DIA max.	25,0	32,0	45,0	65,0	86,0
VALVE SHAFT LENGHTS max.	25,0	35,0	42,0	50,0	50,0
Torque plug	SQ14/SQ17	SQ17/SQ19 SQ22	SQ22/SQ27 SQ36	SQ27/SQ36 SQ46	SQ27/SQ36 SQ46
RECOMMENDED HANDWHEEL	R6	R8	R14/R18	R18/R24	R24/R30
UNIT WEIGHT (Kg)	3	6,0/6,2/6,4	11,0/11,2/11,4	11,0/12,0/18,0	31,0/33,0/34,0

Top pull declutch gearboxes series „P declutch“. (Top pull decluth):

Top pull declutch gearboxes are made from M - F series gearboxes using special declutchable adapter. This model declutches from the top of our actuator using a t- handle to engage and disengage a key from the actuator stem. These are assembler on the mounting bracket above pneumatical or hydraulical actuator.

Performance specifications:

Type	Output torque Nm	Diameter of stem in mm	Slot diameter in stem in mm
MLF	23.781	95,0	25,4
MPF	47.541	114,3	31,7
MTF	79.089	133,5	38,1
M83	112.553	152,4	38,1

Side declutchable gearboxes series „SDT“:

Top pull declutch worm gearboxes SDT are made from MF-IS series gearboxes using top flange adapter with declutchable mechanism inside Operating lever is on the body of top flange adapter. Environmental protection is IP55.

Unit size	M20SD	M30SD
Max. output torque (Nm)	8.000	13.000
Mechanical advantage	57,0	99,0
Input torque (Nm)	140,0	131
Ratio	183:1	309:1
Turns to close	45,75	153,75
Valve mounting flange ISO5211	F16,F20, F25	F20, F25, F30
Top mounting flange ISO5211	F16,F20, F25	F20F F25, F30
Max. valve Shift Dia.	65,0	68
Max. valve Shift lengths	116,0	144,0
Unit weight	60,0	110,0
Recommended handwheel	V600	V600

Installation and assembling instructions for M20SD/M30SD:

a/ The worm gear can be assembled directly on the valve top flange (fig. 1) or alternatively mounted to valve by a mounting bracket (fig. 2). To care, that the position OPEN-SHUT of the valve corresponds to the gearbox position (valve in Open position – worm gear in OPEN position.) To verify this condition, use the local indicator placed on the worm gear.

b/ When the worm gear is assembled on the valve, set the stop screws same as for normal gearbox assembling.

c/ For assembling the pneumatic actuator, follow the manufacturer instructions. Make sure that the pneumatic actuator is in same position (OPEN or SHUT) as the valve/worm gear. Use the position indicator on the worm gear to check this.

d/ To operate the valve by use of the pneumatic actuator, it is necessary, to declutch the worm gear. This will be done by turning the two knobs to OFF position (fig 3.) As the gearbox is now declutched from the system, the position of the valve can be read only from the position indicator of the pneumatical actuator but not from the position indicator of the gearbox.

e/ To engage the gearbox to the system, the two knobs must be turned in direction to ON position. The engagement will be only effective when the position of the gearbox is same as the actuator. Therefore it is necessary, to turn hand wheel and move the position indicator to the correct position. Only in this position, the system will engage and the two knobs will turn in ON position. From this moment, the position indicator of the gearbox shows the valves position.

f/ For disengagement of the gear box, turn the two knobs to the OFF position. Check, that valve and actuator are in the same position.

g/ ATTENTION: We suggest that actuator is equipped with safety device to guarantee that, when the gearbox is in engaged position (knobs in ON position), possible accidental movement of actuator is not allowed, because the system could be damaged.