PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

704021Shaft,shouldered

Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer · NSN 3040-01-188-8580 · FSC 3040 · No Item Name Available
Verified by PartsTable
NSN 3040-01-188-8580 — this item is cataloged by the U.S. Government under National Stock Number 3040-01-188-8580. Primary manufacturer part number: 704021.
Features
  • Shaft,shouldered — FSC 3040
  • First End Style: PLAIN
  • Second End Style: FLAT KEYWAY
  • Material: STEEL
  • Second End Keyway Width: 0.3750 INCHES NOMINAL IN
  • First End Diameter: 1.5748 INCHES NOMINAL IN
  • External Keyway Length: 2.625 INCHES NOMINAL SECOND END IN
  • Second End Keyway Depth: 0.219 INCHES NOMINAL IN
Applications
  • Applications requiring Steel construction
General Description

The Shaft,shouldered, cataloged under National Stock Number 3040-01-188-8580, is classified within Federal Supply Class 3040 (No Item Name Available) of the Mechanical Power Transmission Equipment group. The primary manufacturer of record is Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer. Government technical data includes 11 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 3 commercial cross-references from 1 manufacturer, enabling identification through both NSN and commercial part number lookups. 7 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN3040-01-188-8580
Primary Part Number704021
Item NameShaft,shouldered
FSC / FSG3040 / 30 — No Item Name Available
ManufacturerDover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
StatusACTIVE
First End StylePLAIN
Second End StyleFLAT KEYWAY
MaterialSTEEL
Second End Keyway Width0.3750 INCHES NOMINAL IN
First End Diameter1.5748 INCHES NOMINAL IN
External Keyway Length2.625 INCHES NOMINAL SECOND END IN
Second End Keyway Depth0.219 INCHES NOMINAL IN
Step Quantity4
Largest Step Diameter1.750 INCHES NOMINAL IN
Second End Diameter1.5000 INCHES NOMINAL IN
End SimilarityNOT IDENTICAL
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 7
4820-00-287-5617170C-N INTERCHANGEABLE
Cock,plug
Anderson Brass Co
3020-01-061-0404919934 INTERCHANGEABLE
Gear,spur
Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
3040-01-061-0481915134 INTERCHANGEABLE
Gearshaft,helical
Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
3010-01-069-1276E-4160PC110 INTERCHANGEABLE
Gear Assembly,speed Decreaser
Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
3010-01-184-4659E-3942C DFAR INTERCHANGEABLE
Gear Assembly,speed Decreaser
Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
3010-01-184-4660E3942-NHRB-VERT-5.7 TO 1 INTERCHANGEABLE
Gear Assembly,speed Decreaser
Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
3010-01-225-2484E-3942C INTERCHANGEABLE
Gear Assembly,speed Decreaser
Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer
Cross-Reference Index
Part NumberManufacturer
E-3942 Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer (USA)
E-3942 ITEM 125 Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer (USA)
704021 PRIMARY Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer (USA)
Related Parts
4820-00-287-5617INTERCHANGEABLE
COCK,PLUG
170C-N
3020-01-061-0404INTERCHANGEABLE
GEAR,SPUR
919934
3040-01-061-0481INTERCHANGEABLE
GEARSHAFT,HELICAL
915134
3010-01-069-1276INTERCHANGEABLE
GEAR ASSEMBLY,SPEED DECREASER
E-4160PC110
3010-01-184-4659INTERCHANGEABLE
GEAR ASSEMBLY,SPEED DECREASER
E-3942C DFAR
3010-01-184-4660INTERCHANGEABLE
GEAR ASSEMBLY,SPEED DECREASER
E3942-NHRB-VERT-5.7 TO 1
3010-01-225-2484INTERCHANGEABLE
GEAR ASSEMBLY,SPEED DECREASER
E-3942C

Frequently Asked Questions

What is NSN 3040-01-188-8580?

NSN 3040-01-188-8580 is a Shaft,shouldered, manufactured by Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer, classified under FSC 3040 (No Item Name Available). Status: active.

What are the part numbers for NSN 3040-01-188-8580?

NSN 3040-01-188-8580 has 3 cross-referenced part numbers: E-3942 (Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer), E-3942 ITEM 125 (Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer), 704021 (Dover Pumps & Process Solutions Segment Inc Dba Blackmer Div Blackmer).

What NSN replaces 3040-01-188-8580?

There are 7 known substitutes for 3040-01-188-8580: 4820-00-287-5617, 3020-01-061-0404, 3040-01-061-0481 and 4 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 704021?

Key specifications for 704021: First End Style: PLAIN; Second End Style: FLAT KEYWAY; Material: STEEL; Second End Keyway Width: 0.3750 INCHES NOMINAL IN. 12 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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