NEMA 4-BOLT Four Bolt Flange Mount Specification

SubtitleNEMA Standard 4-Bolt C-Face Mounting Flange

Keywords: NEMA 4-BOLT,motor flange,C-face mount,four bolt flange,mounting standard

Module Feature

4-BOLT is the NEMA standard four-bolt C-face flange specification. It defines uniform bolt circle diameter, pilot diameter and mounting hole distribution for flange mounted motors. This standard ensures interchangeability between motors, gear reducers and pumps with matching 4-bolt interface. Cast flange structure has high rigidity, widely used for close-coupled pump, gearbox and mixer drive assemblies.

Working principle

This is a pure mechanical mounting standard without electromagnetic or dynamic working principle. The four evenly distributed mounting bolts provide stable clamping force between motor flange and driven equipment, ensuring concentricity and preventing offset during operation.

Onboard components

Flange pilot register, four mounting bolt holes, flange sealing surface, locating datum plane.

LED indicators

No onboard LED indicators.

Hardware self-diagnosis

Check flange surface flatness, inspect thread damage of bolt holes, verify pilot register dimension tolerance, check surface crack or deformation.

Programming software

No configuration software, purely mechanical dimension standard.

Electrical & Process Parameters

Model:4-BOLT Brand:NEMA Standard Device type:Motor C-face Flange Mount Standard Standard:NEMA MG1 Function:Mechanical connection interface for motor and driven equipment

Mechanical & Structure

Mounting:Flange face to face coupling Protection class:Depend on matched equipment enclosure Housing:Cast iron / steel flange

Environmental

Operating temperature:-20℃ ~ +80℃ Storage temperature:-30℃ ~ +85℃ Ambient humidity:5~95% non-condensing Certification:NEMA MG1 industrial standard compliant Status: NEMA standard 4-bolt C-face mounting specification

Installation

Align pilot register of motor and mating equipment. Insert four matched bolts and tighten bolts in diagonal sequence to guarantee even clamping force. Keep flange contact surface clean without debris to avoid misalignment.

Interface

C-face pilot locating register, four bolt mounting holes, flat mating sealing surface.

Diagnostic

Excessive vibration: flange misalignment or uneven bolt tightening. Bolt thread damage: over-torque or wrong bolt specification. Runout out of tolerance: deformed flange surface.

Product Brief

NEMA 4-BOLT four bolt C-face flange standard, interchangeable mechanical connection interface for NEMA flange mount motors, pumps and gear reducers.