Concept

SPC-2 is a sanitary electro-pneumatic regulating valve for use in applications which require precision control of pressure, flow, temperature, level in tanks etc.

Working principle

It is remote-controlled by an electrical signal and compressed air. The IP-converter, which is an integrated part of the actuator, converts the electrical signal to a pneumatic signal. This signal conversion is extremely insensitive to pressure shocks. The pneumatic signal is transmitted to the integrated positioner which operates by means of the force-balance principle, ensuring that the position of the actuator piston is directly proportional to the input signal. Signal range and zero point can be adjusted individually. The actuator can be used for split-range operation by using a different measuring spring.

Standard design

The valve consists of valve body, valve plug, lip seal, bonnet and an external actuator. The actuator with the bonnet is fitted to the valve body by means of a clamp. All the moving parts are enclosed in the actuator and therefore well protected against damage and dirt. The actuator has few moving parts, and two main actuator sizes cover all valve sizes.

TECHNICAL DATA

Valves

Max. product pressure: . . . . . 1000 kPa (10 bar).

Min. product pressure: . . . . . Full vacuum.

Temperature range: . . . . . . . . -10°C to 140°C (EPDM).

Flow range Kv (Δ P = 1bar): . . 0.5 to 110 m3/h.

Max. pressure drop: . . . . . . . 500 kPa (5 bar).

Actuator

Air quality

Air connection: . . . . . . . . . . . 6/4 air tubewith air fittingR1/8" (BSP)

Max. pressure: . . . . . . . . . . . 600 kPa (6 bar).

Working pressure: . . . . . . . . 400 kPa (4 bar).

Max. size of particles: . . . . . . 0.01 mm.

Max. oil content: . . . . . . . . . 0.08 ppm.

Dew point: . . . . . . . . . . . . . 10°C below ambient temp. or lower.

Max. water content: . . . . . . . 7.5 g/kg.

I/P converter

Signal range: . . . . . . . . . . . . 4 - 20 mA (standard).

Input resistance: . . . . . . . . . . 200

Inductivity/capacitance: . . . . . Negligible.

PHYSICAL DATA

Valves

Product wetted steel parts: . . . 1.4404 (316L).

Other steel parts: . . . . . . . . . 1.4301(304).

Product wetted seals: . . . . . .EPDM.

Actuator

Actuator cases: . . . . . . . . . .Aluminium with plastic coating.

Diaphragms: . . . . . . . . . . . .NBR with reinforced fabric insert.

Springs: . . . . . . . . . . . . . . .Stainless steel uncovered/spring steel

epoxy resin coated.

Actuator stem: . . . . . . . . . . .Polyamide.

Screws, nuts: . . . . . . . . . . . .Stainless steel, polyamide.

Other parts: . . . . . . . . . . . . .Stainless steel.

Accuracy

Deviation: . . . . . . . . . . . . . .≤1.5%

Hysteresis: . . . . . . . . . . . . .≤0.5%.

Sensitivity: . . . . . . . . . . . . . .<0.1%.

Influence of air supply pressure: ≤0.1% between 1.4 and 6 bar.

Air consumption at steady state

condition: . . . . . . . . . . . . . .With 0.6 bar signal pressure and supply pressures up to 6 bar ≤100

In/h.

Ambient temperature: . . . . . . -25°C to +70°C.

Protection class: . . . . . . . . . .IP 54.

Options

A. Male parts or clamp liners in accordance with required standard.

B. Aseptic version based on SSV Aseptic diaphragm system.

C. 3A approved version (polished).

D. Explosion protection (EEX ia IIc T6) on request.

E. 3A (Sanitary Standard) labelling on request.

F. Lip seal of Nitrile (NBR) or Fluorinated rubber (FPM).

Note!

For further details, see also PD 65036 and instruction IM 70736.

Flow sizes/tube connections

Capacity diagram

For Δ P= 100 kPa (1bar).

TD 424-008

Kvq (m³/h)

Recommended working area

Note! For the diagram the following applies:

Medium: Water (20°C).

Measurement: In accordance with VDI 2173.

Pressure drop calculation

The Kv designation is the flow rate in m3/h at a pressure drop of 1 bar when the valve is fully open (water at 20°C or similar liquids).

To select the Kv value it is necessary to calculate the Kvq value using the following formula:

Where:

Kvq = Kv value at specific flow and specific pressure drop.

Q =Flow rate (m3/h).

Δ P = Pressure drop over valve (bar)

a. SPC-2, normally open (NO) b. SPC-2, normally closed (NC).

Dimensions (mm)