CVS 471, CVS 471-16-80, 470 Series, CVS 471-16-100 Instruction Manual

CVS Controls Series 470

INSTRUCTION MANUAL

Head Office

Website: www.cvs-controls.com Email: [e-mail]

Piston Actuators

The CVS Series 470 is a double acting
pneumatic Piston Actuator, suitable
for use with Globe, Angle, Three Way,
and Reverse acting valves as well as
Steam Equipment. Capable of high
thrust applications to 19,500 lb-f,
with a maximum travel to 8 1/8
inches.

The CVS Series 470 Actuator may be
used in on/off applications, as well as
throttling service when used with a
positioner.

3900 101 Street
Edmonton, Alberta
T6E 0A5
Canad

a

ffice: [phone]

O
Fax: [phone]

Calgary Sales Office

3516 114 Avenue SE
Calgary, Alberta
T2Z 3V6
Canada
Office: [phone]
Fax: [phone]

CVS Series 470 Piston Actuator – Specifications:

Model

Maximum Travel (in)

Piston Area (in2)

CVS 471-16-80

8 1/8

88.5

CVS 471-16-100

8 1/8

130.5

Stem Diameter (in)

Max allowable

Thrust*

Cast

Yoke**

Steel
Yoke

CVS 471-16-80

5

1 1/4

13200

13200

CVS 471-16-100

5

1 1/4

17000

19500

*reduce max thrust by 10% if using a positioner
** Cast Iron Yoke Standard

Standard Input: 3-15psig, 6-30psig or split range

Maximum Cylinder Pressure: 125psig, (*not to exceed max allowable thrust)

Temperature Rating: -30

o

F to 175oF, standard with Nitrile O-Rings

Material Specifications (Standard):
Yoke: Cast Iron (standard) or WCB Steel (optional)
Cylinder and Piston: Aluminum

Seal Bushings: Brass

O-Rings: Nitrile

Other materials may be available upon request, please contact a CVS Controls
representative for more information.

Maximum Travel and Piston Area:

Specifications and Maximum Allowable Thrust:

Model

The CVS 471 Piston Actuator operates by pneumatic air loading pressure to one side of the
piston, and unloading the opposing side. Because no positioner is included, a loading device
such as a 4 way switch valve must be installed if no additional positioner has been ordered for
use in conjunction with the CVS 471 Actuator.

Yoke Boss Diameter

(in)

2 | Page

CVS Series 470 Piston Actuator – Installation

CVS 471 Piston Actuator

Note: Ensure proper safety procedures are followed to avoid personal injury or property
damage.

CVS 471 Piston Actuator Installation

The CVS 471 Actuator should be installed in a location which will allow adequate room for
service, maintenance and removal if required.

1. Mounting of the CVS 471 Actuator is achieved by using the 8 supplied nuts and bolts,
rather than a yoke locknut. Although the actuator may be mounted in any position,
typical installation is with the CVS 471 in the vertical position above the control valve.

2. Stem connections should be made to clamp the actuator stem and valve plug stem
together to ensure proper travel of the valve.

Stem Connections:

Note: Do not rotate the valve plug once it is seated to avoid damage to seating surface. Use
proper tools to avoid damaging the valve plug stem during travel adjustments. Should the stem
connections not be made properly in the stem connector, thread damage, or improper
operation may occur. The amount of each stem pressed in the stem connector should be equal
to or greater than the diameter of the stem itself. DO NOT loosen the stem connector cap
screws unless all pressure or force has been removed from the stems.

Typical Stem Connection

3 | Page

CVS Series 470 Piston Actuator – Installation

Push Down to Close Installation – Direct Acting Valves:

1. After installation of the CVS 471 Actuator to the control valve set the actuator to the top of
its stroke and ensure the valve plug is in the closed position. Install two valve stem
locknuts, as well as travel indicator disc (if used) all the way onto the stem threads.

2. Apply pressure to the actuator until the piston rod of the CVS 471 has moved down from
the top of its stroke to the correct valve travel required.

3. Attach the Stem Connector to the Piston Rod and Valve Stem, tighten the 4 hex bolts once
in position.

4. Raise the stem locknuts and travel disc (if used) and secure against the bottom of the stem
connector.

5. Once the Stem Connector is secured, cycle the CVS 471 Actuator to verify the required
total travel settings are met, and that the valve plug seats properly before the actuator
makes contact with the lower travel stop adjustment.

Adjustments if needed:

Should minor travel adjustments be necessary, loosen the hex bolts slightly on the stem
connector. Tighten the stem locknuts together and make minor adjustments by turning the
valve stem into or out of the stem connector as needed using a wrench on the stem locknuts.

For major adjustments, repeat the stem connection of the valve and actuator as listed above.

6. After required travel has been achieved, secure the Stem Connector hex bolts. Lock the
stem locknuts against the Stem connector. Finally, adjust the actuators travel scale on the
yoke to reflect the correct valve position.

7. Using a gauge to measure the pressure to the actuator, make final adjustments to the
actuator, or positioner if used, setting the start and end points of travel for the required
instrument range.

4 | Page