PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

6656Diaphragm,valve,flat

Imi Cash Valve Inc · NSN 4820-00-690-2068 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-690-2068 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-690-2068. Primary manufacturer part number: 6656.
Features
  • Diaphragm,valve,flat — FSC 4820
  • Hole Diameter: 0.450 INCHES NOMINAL IN
  • Style Designator: FLAT
  • Outside Diameter: 5.850 INCHES NOMINAL IN
  • Bolt Hole Quantity: 10
  • Material Thickness: 0.080 INCHES NOMINAL IN
  • Material: RUBBER SYNTHETIC
  • Bolt Circle Diameter: 5.125 INCHES NOMINAL IN
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Rubber Synthetic construction
General Description

The Diaphragm,valve,flat, cataloged under National Stock Number 4820-00-690-2068, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Imi Cash Valve Inc. Government technical data includes 7 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 9 commercial cross-references from 6 manufacturers, enabling identification through both NSN and commercial part number lookups. 10 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-00-690-2068
Primary Part Number6656
Item NameDiaphragm,valve,flat
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerImi Cash Valve Inc
StatusACTIVE
Hole Diameter0.450 INCHES NOMINAL IN
Style DesignatorFLAT
Outside Diameter5.850 INCHES NOMINAL IN
Bolt Hole Quantity10
Material Thickness0.080 INCHES NOMINAL IN
MaterialRUBBER SYNTHETIC
Bolt Circle Diameter5.125 INCHES NOMINAL IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 10
5133-00-061-628844476 INTERCHANGEABLE
Drill,twist
Greenfield Industries Inc
3120-00-237-76826656 INTERCHANGEABLE
Bearing,sleeve
Quincy Compressor Division of Coltec Industries Inc Dba Quincy Compressor Div Quincy Compressor
4940-00-318-9078 INTERCHANGEABLE
Adapter
4820-00-450-9840665-6 INTERCHANGEABLE
Cartridge,check Valve
Admiral Valve Llc Dba Cpv Manufacturing
5330-00-556-7134 INTERCHANGEABLE
Packing Material
5950-00-813-8352SM-D-415301 INTERCHANGEABLE
Transformer,audio Frequency
Us Army Communications & Electronics Materiel Readiness Command Logistics Engineering Dir
5950-00-947-6643 INTERCHANGEABLE
Coil,radio Frequency
4320-01-037-4793622/6656 INTERCHANGEABLE
Diaphragm Assembly
Coffin Turbo Pump Inc
5330-01-295-68296656 INTERCHANGEABLE
Retainer,packing
Davis Frank T and Associates
4820-01-438-15586290-G501 INTERCHANGEABLE
Cock,poppet Drain
Howell Laboratories Inc Dba Howell Laboratories Inc
Cross-Reference Index
Part NumberManufacturer
6656 PRIMARY Imi Cash Valve Inc (USA)
200110AHPC486 Siemens Energy, Inc. Dba Dresser-Rand (USA)
200110AHPC486 Dresser-Rand Co Worthington Compressor Opn a Joint Venture (USA)
4820PL1380156 Jednolity Indeks Materialowy - Uniform Material Index (POL)
4750B Siemens Energy, Inc. Dba Dresser-Rand (USA)
200110AHPC486 Curtiss-Wright Electro-Mechanical Corporation Dba Curtiss-Wright Steam and Air Solutions Div Steam and Air Solutions (USA)
200110AHPC486 Curtiss-Wright Electro-Mechanical Corporation Dba Curtiss Wright Engineered Pump Division Use CAGE Code 0ubg9 for Cataloging (USA)
4750B Dresser-Rand Co Worthington Compressor Opn a Joint Venture (USA)
4750B Curtiss-Wright Electro-Mechanical Corporation Dba Curtiss-Wright Steam and Air Solutions Div Steam and Air Solutions (USA)
Related Parts
5133-00-061-6288INTERCHANGEABLE
DRILL,TWIST
44476
3120-00-237-7682INTERCHANGEABLE
BEARING,SLEEVE
6656
4940-00-318-9078INTERCHANGEABLE
ADAPTER
4820-00-450-9840INTERCHANGEABLE
CARTRIDGE,CHECK VALVE
665-6
5330-00-556-7134INTERCHANGEABLE
PACKING MATERIAL
5950-00-813-8352INTERCHANGEABLE
TRANSFORMER,AUDIO FREQUENCY
SM-D-415301
5950-00-947-6643INTERCHANGEABLE
COIL,RADIO FREQUENCY
4320-01-037-4793INTERCHANGEABLE
DIAPHRAGM ASSEMBLY
622/6656
5330-01-295-6829INTERCHANGEABLE
RETAINER,PACKING
6656
4820-01-438-1558INTERCHANGEABLE
COCK,POPPET DRAIN
6290-G501

Frequently Asked Questions

What is NSN 4820-00-690-2068?

NSN 4820-00-690-2068 is a Diaphragm,valve,flat, manufactured by Imi Cash Valve Inc, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-690-2068?

NSN 4820-00-690-2068 has 9 cross-referenced part numbers: 6656 (Imi Cash Valve Inc), 200110AHPC486 (Siemens Energy, Inc. Dba Dresser-Rand), 200110AHPC486 (Dresser-Rand Co Worthington Compressor Opn a Joint Venture), 4820PL1380156 (Jednolity Indeks Materialowy - Uniform Material Index), 4750B (Siemens Energy, Inc. Dba Dresser-Rand) and 4 more.

What NSN replaces 4820-00-690-2068?

There are 10 known substitutes for 4820-00-690-2068: 5133-00-061-6288, 3120-00-237-7682, 4940-00-318-9078 and 7 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 6656?

Key specifications for 6656: Hole Diameter: 0.450 INCHES NOMINAL IN; Style Designator: FLAT; Outside Diameter: 5.850 INCHES NOMINAL IN; Bolt Hole Quantity: 10. 7 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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