Submittal Sheet

Optional features and accessories available for this
Macon product are an extra charge, and not included
in the standard model price.
www.maconbalancing.com
Tunstall Corporation
118 Exchange Street · Chicopee, MA 01013
Phone [phone] · Fax [phone]
Section: Components Bulletin-MB-MB-0915a
Model MB
Submittal Data
Model MB is a venturi style manual balancing valve with 100% positive
shut-off full port plated ball. Permanently installed venturi section,
Teflon seats, double o-ring shaft seals, Pressure/Temperature readout ports,
adjustable memory stop with position indicator and union end with o-ring
seal. Available with multiple combinations of end connection types and sizes.
SPECIFICATIONS
Pressure Ratings: 600 PSI (4140 kPa)
Temperature Ratings: 250ºF (120ºC)
Accuracy: ± 3% of flow rate
Body Material: Forged Brass
End Connections: Brass - Fixed End: SWT, FNPT
Union End: SWT, FNPT & MNPT
Flow Element: Brass Venturi, Permanently installed
Seals: EPDM
Seats: Teflon
Ball: Chrome Plated Brass. Optional 316 Stainless Steel.
Stem: Brass. Optional 316 Stainless Steel.
Handle: Full size Zinc Plated lever with Vinyl Grip
Memory Stop: Zinc Plated Steel
Available Options: “PTV” combination PT & Air Vent, hose end Drain Valve & Extensions
MANUAL
NOMINAL DIMENSIONS & WEIGHTS
MODEL
SIZE
Flow Range
GPM (10”-100”)
A
B C D E
*T
SWT
Cv
WEIGHT
in mm FNPT SWT lbs
kg
MB1A-050-L
MB1B-050-H
1/2” 15
(L) 0.4 - 1.3
(H) 1.3 - 4.0
in 3.46 3.55 2.30 3.66 1.98 1.82 1.50
(L) 2.0
(H) 5.9
1.31 0.59
mm 87.88 90.17 58.42 93.02 50.29 46.20 38.10
MB1A-075-L
MB1B-075-H
3/4” 20
(L) 0.4 - 1.3
(H) 1.3 - 4.0
in 3.60 3.67 2.30 3.66 1.98 1.82 1.55
(L) 2.0
(H) 5.9
1.34 0.61
mm 91.44 93.22 58.42 93.02 50.29 46.20 39.37
MB2A-075-L
MB2B-075-H
3/4” 20
(L) 1.6 - 5.0
(H) 4.0 - 13.0
in 3.87 3.98 2.56 3.66 2.08 2.05 1.56
(L) 7.6
(H) 13.0
1.81 0.82
mm 98.30 101.12 65.03 93.01 52.83 52.07 39.62
MB2A-100-L
MB2B-100-H
1” 25
(L) 1.6 - 5.0
(H) 4.0 - 13.0
in 4.00 4.14 2.56 3.66 2.08 2.05 1.75
(L) 7.6
(H) 13.0
1.81 0.82
mm 101.60 105.16 65.03 92.96 52.83 52.07 44.45
MB3A-125 1-1/4” 32 7.25 - 23.0
in 5.39 5.56 3.70 5.03 2.44 2.43 1.80
29.00 4.59 2.08
mm 136.91 141.22 93.98 127.76 61.98 61.74 45.72
MB3B-150 1-1/2” 40 9.5 - 30.0
in 6.06 6.38 4.16 5.66 2.83 2.43 1.80
45.00 4.97 2.25
mm 153.92 162.05 105.66 143.76 71.88 61.74 45.72
MB4A-200 2” 50 15.0 - 50.0
in 6.57 7.36 4.45 5.66 2.83 2.74 1.98
77.40 7.10 3.20
mm 166.88 186.94 113.03 143.76 71.83 69.67 50.29
* Please reference the tailpiece data sheet #Bulletin-MB-TP for other sizes and connections.
Dimensions not for construction purposes unless certified by factory.
STANDARD COMPONENTS
Pressure / Temperature test port with brass body, dual durometer EPDM core, brass cap with O-ring seal
and neoprene retainer strap. Accepts standard 1/8” (4mm) gauge adapter or thermometer stem. Rated to
500 PSI (3450 kPa) and 275ºF (135ºC)
Memory stop with position indicator, zinc coated steel.
Please reference data sheet #Bulletin-MB-Accessories for optional accessories.