Reduced Port - Series: 15

Size: 3" thru 14" for 125/150 lb. Flanging
Operating Temperature: To 450°F with standard materials
To 900°F with optional materials

Design Standard

The PDC “Reduced Port” series butterfly valve is available in sizes from 3″ thru 14″ in a combination of materials and optional features suitable for most mid-range differential pressures and service conditions.


Size Range:
3" thru 14" for 125/150 lb. Flanging
To 450°F with standard materials
To 900°F with optional materials
Pressure Rating:
Varies with size. See Reduced Port Brochure
Shutoff Rating:
ANSI Class II & Class III available with optional seats
Body Style:

Design Features

  • Inboard bushings of graphited bronze for long life, non-freezing, low torque characteristics.
  • Close tolerance machining for minimal leakage and dependable flow characteristics.
  • Adjustable packing-Graphited TEFLON ® Braid. Valves can be repacked without removal from line.
  • Rugged mounting pads drilled and tapped for ease of installing actuating equipment and accessories.
  • Flatted, keywayed or hexed ends on shafts are available to facilitate factory or field mounting of all types of actuating equipment.
  • Lightweight, solid ring, wafer design for ease of installation. Four holes to insure proper alignment without transfer of pipe stresses to the valve body.


  • Blower Equipment
  • Compressor Equipment
  • Boiler Equipment
  • Environmental Systems
  • V.A.C
  • Industrial Process Furnaces
  • Oil Gas/Refining
  • Power Generation/Co-Generation
  • Water & Sewage
  • Stationary Engines
  • Chemical Equipment
  • Mining Equipment
  • Gas Recovery Systems

Standard Materials and Seat Construction

Body:Cast Iron
Disc:Cast Iron
Shaft:416 Stainless Steel
Bushing:Graphited Bronze
Packing:Graphited Teflon Braid
Packing Nut:Brass

Optional Materials and Seat Construction

Body:High Temperature Iron, Carbon Steel, 316 Stainless Steel, 304 Stainless Steel
Disc:High Temperature Iron, Carbon Steel, 316 Stainless Steel, 304 Stainless Steel
Shaft:316 Stainless Steel, 304 Stainless Steel, Incoloy, Monel
Seat:Angle (3″-4″), Metal Step (3″-14″), Tadpole Step (8″-14″)
Bushing:316 Stainless Steel, 304 Stainless Steel, Glass Filled Teflon, Metcar, Macor
Packing:High Temperature Braid, Pure Teflon Braid, Teflon V-Ring
Packing Nut:316 Stainless Steel
  1. Body
  2. Disc
  3. Power Shaft
  4. Idle Shaft
  5. a. Bushing b. Bushing Extension
  6. Braided Packing
  7. Adjustable Packing Nut
  8. Shaft Retaining Pin

Chart or Graph

*Torque, Lb-In, Required for PDC Swing Thru Butterfly Valves with Disc in Closed Position for Temperatures up to 450° Fahrenheit

*Below torques only apply to normal clean service conditions.

3 x 2.55051535558606365707580859095100113125
4 x 3505154576164687178859299106113120138155
5 x 451525967768493101118135152169186203220263
6 x 55153637588100113125150175200225250275300
8 x 652546988107126145164202240278316354
10 x 8124128158195233270308345420495570645720795
10 x 1212913717120525629034137546054563071580088597011401310
14 x 12132143189235304350419465580695810925104011551270

Typical Dimensions: 3″ thru 14″

Size (inch)ABCDEFHMax. ΔP Approx. Wt. (Lb)
3 x 2-1/22-1/24-3/85-7/81-1/25-1/44-1/41/215012
4 x 334-7/86-3/81-1/26-1/44-1/41/215015
5 x 445-3/86-7/81-1/27-3/84-1/41/212520
6 x 555-7/87-3/81-1/28-1/24-1/41/210027
8 x 6 67-3/49-5/81-7/810-3/45-1/83/48060
10 x 888-3/410-5/81-7/8135-1/83/49065
12 x 10109-1/211-5/81-7/815-1/45-1/83/47080
14 x 121210-1/212-1/81-7/816-3/85-1/83/45086

* “G” Length and configuration of the shaft end will vary to accommodate specific actuators. Refer to the accessory section for typical flatted, keywayed, and hexed end configurations available.

MAX. ∆P is based on 0° disc position, using standard materials of construction at a maximum temperature of 450° Fahrenheit.

Consult factory for MAX. ∆P for elevated temperatures.

Cv Values for PDC Swing Thru Butterfly Valves

By definition, Cv is the flow coefficient of a control device or flow restriction. Cv is defined as the number of US gallons of 60°F water per minute which will flow through the given restriction with a one pound per square inch pressure drop.

Cv Values

(Flow in GPM of 60°F water at 1 psi pressure drop Specific Gravity=1)

VALVE SIZEDisc Angle, Degress
3 x 2.54820345684126178194
4 x 3614305185132202279370
5 x 413285498159257391550747
6 x 52143881582654296369131272
8 x 6306312622838263295513701999
10 x 8531112254066801125169825913853
12 x 108317435163510631759265540526361
14 x 1212025250691415312533382658359164