Model: 4644-1

Safety Relief Valve

Properties:

Thread Class

3a 1st end

Thread Direction

Right-hand 1st end

Flow Control Device

Poppet

Disk Loading Method

Spring

Connection Style

G42 flared (tube) 1st end

Connection Style

Flared (tube) 1st end

Valve Operation Method

Automatic

Connection Type

Threaded external tube 1st end

Thready Qty Per Inch (tpi)

20 1st end

Thread Size

0.437 inches 1st end

Seat Angle

37.0 degrees 1st end

Opening Pressure Setting

1425.0 pounds per square inch

Outside Diameter Tube Accommodated

0.250 inches 1st end

Material

Aluminum alloy body

Material

Aluminum alloy seat

Surface Treatment

Anodize

Surface Treatment Specification

Mil-a-8625 military specification single treatment response

Style Designator

Angle

Thread Series Designator

Unf 1st end

NSN

4820-00-450-6539

Part Number

4644-1

Description

Valve,safety Relief

CAGE

78357

A valve designed to automatically release excessive pressures. It is actuated by static pressure upstream of the valve and is used as a safety valve or relief valve, and may be set to close at a predetermined pressure. It is not designed for regulation of continuously fluctuating loads. It may be inline or cartridge (manifold) design. Excludes valve (1), relief, pressure and temperature.

Part 4644-1 NSN 4820-00-450-6539

INC

FIIG

Concept No.

App. Key

Cond. Code

Status

INC:

05488

FIIG:

A046B0

Concept No.:

App. Key:

Cond. Code:

Status:

Material Classification

Hazardous material, precious metals, criticality, enviroment, and electrostatic discharge indicators

HMIC

PMIC

ESD/EMI

ENAC

MMAC

CRITL

HMIC:

PMIC:

ESD:

MMAC:

CRITL:

Freight Classification

NMFC

UFC

LTL

LCL

WCC

TCC

SHC

ACC

NMFC:

127220

UFC:

64490

LTL:

77.5

LCL:

77.5

WCC:

594

TCC:

SHC:

ACC:

Equipment for Aircraft

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Schedule B and Export

Schedule B: 8481400000
SITC: 74740
End Use: Industrial machines, other
NAICS: 332911
USDA: 1

Freight Class: Safety or relief valves