Control valves

Safety valves

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TI-S13-25

CH Issue 11

Cert. No. LRQ 0963008

SV73

Cast Iron

Safety Valve

Description

The SV73 cast iron series valves are built in conformance to Section I and VIII of the ASME Boiler and Pressure Vessel Code. They are

primarily intended for use on power boilers and unfired pressure vessels where ASME Section I and VIII stamped valves are required.

Applications

Protection of steam systems downstream of pressure regulating stations, on inlet to such equipment as air coils, heat exchangers and

process vessels. Also for use on flash recovery vessels on condensate return systems to protect vessels. Air systems to protect accumulation

vessels and air equipment from overpressurisation. Steam boilers and generators.

Available types

The SV73 is available with cast iron body and stainless steel trim in orifice sizes from 'J' to 'R'. It has an open bonnet and easing lever and is

available with screwed or flanged connections.

Certification

A manufacturers' Typical Test Report is provided as standard for each valve which will include valve set and hydraulic test pressure. Also

available on request is material certification in accordance with EN 10204 3.1.

Standards and approvals

Approved by National Board of Boiler and Pressure Vessel Inspectors to ASME Boiler and Pressure Vessel Code Sections I and VIII.

Seat tightness is in accordance with ANSI/API STD 527-1992.

If National Board 'V' or 'UV' stamp is required, then this must be specified at the time of ordering.

Important note: SV73 safety valves are not marked and therefore not to be used within the EEA.

Sizes and end connections

11⁄2" x 21⁄2" to 3" x 4"

11⁄2" x 21⁄2" to 3" x 4"

3" x 4" to 6" x 8"

Inlet /outlet screwed female NPT.

Inlet flanged ANSI class 250 RF,

Inlet flanged ANSI class 250 RF,

Outlet screwed female NPT.

Outlet flanged ANSI class 125 FF.

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Pressure/temperature limits

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Pressure psi g

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The product must not be used in this region.

A - B Limit for valves with a flanged inlet.

C - D Limit for valves with a screwed inlet.

Body design conditions

ANSI 250

250 psi g

5 psi g

406°F

446°F

-20°F

Steam

3%

Steam

10%

Air / gas

10%

Steam 2 - 6%

Steam

7%

Tested at a maximum inlet cold hydraulic test pressure of 600 psi g

Local regulations may restrict the use of this product to below the conditions quoted.

In the interests of development and improvement of the product, we reserve the right to change the specification without notice.

Set pressure

range

Temperature

Performance

data

Maximum

Minimum

Maximum

Minimum

Overpressure

Blowdown limits

Screwed inlet

Flanged inlet

ASME I

ASME VIII

ASME I

ASME VIII

ISO 9001

C

Steam

saturation

curve

D

B

7%

0.955

0.955

Maximum permitted backpressure up to:

10% of set pressure

Derated coefficient

of discharge values

Air / gas

Steam

Air / gas

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© Copyright 2007

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