Brochure

MK-6xxx Series
Valve Actuators, Proportional
Model Chart
Specifications
Proportional pneumatic actuator with 50 sq. in.
(323 cm
2
) effective diaphragm area used to control
1-1/2 in. to 2 in. VB-7xxx series, 2-1/2 in. to 5 in.
VB-8xxx series, 2-1/2 in. to 4 in. discontinued
VB-9xxx series and 4 in. to 6 in. discontinued
VB-9323 series valves.
Features:
• Rugged die cast aluminum construction.
• Rolling diaphragm.
• Three spring ranges for various applications.
• Start point adjustable r2 psi.
Model No.
Nominal Spring Range
a
a
Nominal (no load) spring ranges based on maximum 1/2 in. (13.7 mm), 1 in. (25.4 mm) or 1-1/2 in. (33.1 mm) stroke for MK-6911.
Nominal Stroke in. (mm)
psig kPa
MK-6601 3 to 8 21 to 55 1/2 (13.7)
MK-6611 5 to 10 34 to 69 1/2 (13.7)
MK-6621 8 to 13 55 to 90 1/2 (13.7)
MK-6801 3 to 8 21 to 55
1 (25.4)MK-6811 5 to 10 34 to 69
MK-6821 8 to 13 55 to 90
MK-6911
bc
b
MK-6911 is only used on 6 in. VB-8xx3-0-5-16. MK-6911 and MK-6921 were used on discontinued 4 to 6 in. VB-9323-0-5-x.
c
Recommended for field replacements only where 20 psi air supply pressure is not available and/or required close-off pressure is less than 125 psi.
5 to 10 34 to 69 1-1/2 (33.1)
MK-6921
b
8 to 13 55 to 90 1-1/2 (33.1)
Construction
Housing Die cast aluminum.
Diaphragm Replaceable beaded molded neoprene (Part number PNV-202).
Stroke Refer to Model Chart.
Spring Retracts actuator shaft and raises valve stem on loss of air pressure.
Nominal spring range Refer to Model Chart.
Starting point Adjustable r2 psig (14 kPa).
Maximum air pressure 30 psig (207 kPa).
Ambient temperature limits
Shipping -40 to 220qF (-40 to 104qC).
Operating -20 to 220qF (-29 to 104qC).
Air connections 1/8 in. FNPT.
Valve linkage Refer to Accessories (order separately).
Mounting In any upright position with actuator head above the center line of the valve body.
Dimensions 7-3/4 H x 10-1/2 W x 10-1/2 D in. (199 x 267 x 267 mm).
MK
-
6
x
x
Series
MK-68x1
MK-6911
MK-6921
MK-66x1
F-27383-1 © Copyright 2006 TAC. All Rights Reserved. 55