Emerson 168H Manual de Instruções descarregar pdf

168, 168H, and 68 Series

D100275X012

Instruction Manual

Form 2256

December 2008

www.emersonprocess.com/regulators

168, 168H, and 68 Series Three-Way

Switching Valves

Introduction

The 168 and 168H Series pneumatically operated

three-way snap-acting switching valves (Figure 1) are

used to switch pressures on and off in response to a

predetermined change in an input signal pressure.

In operation, increasing pressure applied to the top of

the diaphragm through port D (see Figure 2) moves

the stem and upper range adjusting nut toward the

trip lever. When the diaphragm pressure reaches

the predetermined upper tripping pressure, the upper

adjusting nut pivots the trip lever to move the rocker

assembly to its alternate position, closing port C

and opening port B. When decreasing pressure to

the diaphragm at port D reaches the lower tripping

pressure, the spring moves the stem and lower range

adjusting nut to return the rocker to its original position,

closing port B and opening port C.

The 68 Series (Figure 4) three-way snap-acting body

assemblies can be used alone, or to form the valve

body portions of 168 or 168H Series switching valves.

With the addition of the lever knob (key 11, Figure 4)

to a Type 68-1 body assembly, a Type 68-2 manual

switching valve body assembly is formed.

Only personnel qualied through training or experience

should install, operate, and maintain these valves. If

there are any questions concerning these instructions,

contact your local Sales Ofce before proceeding.

W1932

Figure 1. Exterior of 168 Series Switching Valve

Figure 2. Construction Details of

168 Series Switching Valve

DIAPHRAGM

SPRING

ROCKER

ASSEMBLY

BODY

BODY SPRING

TRIP LEVER

LOWER RANGE

ADJUSTMENT NUT

STEM

UPPER RANGE

ADJUSTMENT NUT

M1045

INLET PRESSURE

OUTLET PRESSURE

ATMOSPHERIC PRESSURE

LOADING PRESSURE

1 2 3 4 5 6 7 8

Resumo do Conteúdo

Página 1 - Switching Valves

168, 168H, and 68 SeriesD100275X012Instruction ManualForm 2256December 2008www.emersonprocess.com/regulators168, 168H, and 68 Series Three-Way Switch

Página 2 - 168, 168H, and 68 Series

168, 168H, and 68 Series2SpecicationsMaximum Allowable Pressures Diaphragm168 Series: 100 psi (6,90 bar)168H Series: 150 psi (10,3 bar)Body: See Tabl

Página 3

168, 168H, and 68 Series3168 and 168H Series AdjustmentDetermine the desired upper and lower switching pressures (the high and low values of diaphragm

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168, 168H, and 68 Series4Maintenance!WARNINGTo avoid personal injury or property damage from sudden pressure release or uncontrolled process uid, iso

Página 5

168, 168H, and 68 Series5Parts OrderingWhen corresponding with the local Sales Ofce about this equipment, state the type number and all other pertine

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168, 168H, and 68 Series6RESET LEVERTRIP LEVERSECTION D-D43A8117-BB1199-1DETAIL OF MANUAL RESET SWITCH FOR USE WITH EITHER 168 OR 168H SERIESDU8774-D1

Página 7

168, 168H, and 68 Series7TRIP LEVER DETAIL OF TYPE 68-2 BODYFOR MANUAL OPERATIONABCCU8794-FCOMPLETE TYPE 68-1 OR 68-3 BODYFigure 4. 68 Series Switchi

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168, 168H, and 68 SeriesThe Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their prospective