Flowserve Valtek Beta Positioners for Control Valves Instrukcja Użytkownika Pobierz pdf

24-1

Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611

Valtek No. 49035

Valtek Beta Positioners

General Information

This bulletin contains instructions for installing, cali-

brating, troubleshooting, and performing maintenance

as required for the Valtek

Beta Positioner mounted on

control valves.

Instructions for maintaining and calibrating the NT 3000

I/P module are contained in Installation, Operation,

Maintenance Instructions 47, NT 3000 Series Electro-

pneumatic Transducer Module. For calibration and

maintaining the remote I/P see Installation, Operation,

and Maintenance Instructions 30, Electro-pneumatic

Transducer.

Product users and maintenance personnel should read

thoroughly and follow exactly the instructions contained

in this bulletin prior to operation of the positioner. If there

is any question concerning this bulletin, call your Valtek

representative.

To avoid possible injury to personnel or dam-

age to equipment, WARNING and CAUTION

notes must be strictly adhered to. Modifying

this product, substituting non-factory or infe-

rior parts, or using maintenance procedures

other than outlined could drastically affect per-

formance, be hazardous to personnel and

equipment, and may void existing warranties.

NOTE: Numbers in parenthesis correspond to the part

item numbers in Figure 17.

Beta Positioner Overview

The Valtek Beta Positioner is available with either a

pneumatic (P/P) module for air control signals or an

electro-pneumatic (I/P) module for milliampere electri-

cal control signals. It is double-acting, capable of sup-

plying air to either side of the actuator piston while

exhausting the other side to the atmosphere. The unit is

adjustable to two and three-way split range without

special feedback springs. The Valtek Beta positioner

can be interchanged with the 80R and XL positioners

without changing the brackets or takeoff arms.

The Beta Positioner with I/P module is intrinsically safe

for FM/CSA class 1, division I, groups A, B, C, and D;

class II, groups E, F, and G, and CENELEC EEx ia IIc,

when installed with the appropriate energy limiting

safety barriers (See Figure 1). It is also explosion proof

for FM/CSA class II, groups E, F, and G, and CENELEC

EEX d IIb + H

. Since the positioner is insensitive to

supply pressure changes and can handle supply pres-

sures from 30 to 150 psi a supply regulator is usually not

required; however, an air filter is highly recommended.

NOTE: The air supply should conform to ISA Standard

S7.3 (a dew point at least 18

F below ambient tempera-

ture, particle size below 5 microns, oil content not to

exceed 1 part per million).

Positioner Operation

The Beta Positioner is a force-balanced instrument.

Figure 2 shows a Beta Positioner, with either a pneu-

matic or electro-pneumatic (I/P) module, installed on a

double-acting actuator for air-to-open action. Position-

ing is based on a balance of two forces; one proportional

to the instrument signal and the other proportional to the

stem position.

With the I/P model, the current signal is first converted

to a 3-15 psi air signal. For the pneumatic model, the

3-15 psi signal is passed directly into the positioner. The

pressure signal acts upon the diaphragms in the instru-

ment signal capsule creating a downward force. The

motion of the actuator stem is transmitted to the top end

of the feedback spring through the follower arm and

cams. As a result, tension in the feedback spring will

vary as the stem position changes.

for Control Valves

1 2 3 4 5 6 ... 19 20

Podsumowanie treści

Strona 1 - Valtek Beta Positioners

24-1Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Valtek No. 49035Valtek Beta PositionersGeneral InformationThis bulletin conta

Strona 2

24-10Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611100 90 80 70 60

Strona 3 - I/P Module Operation

24-11Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611100 90 80 70 60

Strona 4

24-12Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611100 90 80 70 60

Strona 5

24-13Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611* All of the above parts are in stock, and can be purchased in any one of 3

Strona 6 - Cam Characteristic Chart

24-14Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Table III: Linear Actuator Follower ArmsActuator Stroke Spud FollowerSize (i

Strona 7 - Calibration

24-15Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611SPARE PART KITSBETA POSITIONER (see Figure 17)Kit 1 - StandardPart No. 1003

Strona 8 - F below

24-16Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611CAM KITS (Rotary Valves)Kit 14 - StandardPart No. 10037441Item No. Descripti

Strona 9 - Capsule Assembly

24-17Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611SPARE PART KITS (continued)INSTRUMENT CAPSULE KITSKit 17 - Standard input c

Strona 10 - Percent Signal (Air-to-Open)

24-18Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Kit 33 - Positioner Cover KitPart No. 10035439Item No. Description Quantity1

Strona 11

24-19Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Beta Positioner TroubleshootingFailure Probable Cause Corrective ActionValve

Strona 12

24-2Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Figure 1: Intrinsically Safe Installation SchematicFigure 2: Positioner Schem

Strona 13 - Positioner Parts List*

Strona 14

24-3Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611A decrease in the instrument signal reverses the de-scribed actions causing a

Strona 15 - ZERO ARM KITS

24-4Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Hole AL-RL-D Air-to-Open Air-to-Close (Air-to-R

Strona 16 - CAM KITS (Linear Valves)

24-5Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Figure 7: Beta Positioner with NT 3000 Transducer3. If not welded to the stem

Strona 17 - ADAPTER MANIFOLD KITS

24-6Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Figure 9: Installation for Cam Return SpringFigure 8: Beta Positioner Install

Strona 18 - POSITIONER BASE KITS

24-7Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611of the cam shaft nut (59). Slide the cam shaft nut(59) through the outer bear

Strona 19

24-8Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611Zero Adjusting PotSpan Adjusting PotMinimum PressureCutoffGrounding ScrewCirc

Strona 20

24-9Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 86114. Reattach the feedback screw to the new instrumentdiaphragm assembly (49)