Micrometers    Micrometers     Micrometers    Micrometers

Image Credit: Inspec Inc. | Pratt & Whitney Measurement Systems, Inc. | Starrett | PI (Physik Instrumente) L.P.

   

Mechanical micrometers are instruments for precision dimensional gaging consisting of a ground spindle and anvil mounted in a C-shaped steel frame.  Noncontact laser micrometers are also available. Mechanical micrometers are available in Vernier scale, digital and dial variations. Micrometers provide precise, quantitative measurements of a product's or component's attributes such as thickness, depth, height, length, I.D., O.D., roundness or bore.  Specialized micrometers are available for the measurement of threads, gear teeth and tube wall thickness.  Laser micrometers are especially effective in inline gaging applications of high speed materials.

 

Common Features

   
Common micrometer types include external, internal, bore, height, laser, micrometer head, and thread.  External micrometers are capable of measuring an outer diameter (OD) or outside feature of a part or component.  Internal micrometers are capable of measuring an inner diameter (ID) or inside feature or cavity of a part or component.  Bore micrometers have the ability to measure the inside diameter of a hole, bore, or blind hole at shallow to very deep (~0.03m inches to several feet) depths into the bore.  Height micrometers are tailored for height measurement.  Laser micrometers use optical, laser, or video-based technology to measure dimensional features.  Micrometer heads or jig borer micrometers consist only of the spindle and drum portion (no frame or anvil).  Micrometer heads are OEM components built into microscopes, machine tools, medical equipment or other metrological systems to provide precision measurement or positioning.  Jig borer micrometers and end measuring rods (fixed standard) are commonly used to set spacing and table locations.  Thread micrometers are designed for measuring thread size, pitch, or other parameters.  Micrometers can be available in sets of several gages and accessories packaged into a kit usually in a case with adjusting tools. Tool kits sometimes contain alternate extensions and contact tips, holders, bases, or standards.

    

Important Parameters In Selecting

   
Important parameters to consider when specifying micrometers include range and resolution.  The range of the micrometer is the total range length or dimensional range that the gage can measure.  The resolution is the best or minimum resolution for gages with digital displays.  Measurement units for micrometers can be either English or metric.  Some micrometers are configured to measure both.  The display on the micrometer can be non-graduated meaning that the micrometer has no display, dial or analog, digital display, column or bargraph display, remote display, or Vernier scale.

    

Optional Features and Mounts

   
Micrometers come with cylindrical anvils and spindles with flat carbide or hardened steel contacting faces.  Specialized anvils or spindles are also available, these include ball anvil, blade or spade anvil, flange of disc (gear tooth), pin or reduced face, point anvil (thread gaging), or v anvil or 3-point.  Mounting options for micrometers include handheld or portable, machine mounted, benchtop or floor, and automatic or inline.  Micrometers may be supplied with plastic, heat insulating handles or holders.  The insulating handles help prevent measurement errors in the gage that could be caused by the heat from a human hand.  Machine travel enabled micrometers are typically mounted on a machine or are built into a product including machine tools, microscopes, and other instruments requiring precision dimensional measurement or position control.

   

Related Standards

   


Related Products & Services

  • Bore and ID Gages

    Bore and ID gages are designed for internal diameter dimensional measurement or assessment.

  • Calipers

    Calipers typically use a precise slide movement for inside, outside, depth or step measurements. Some caliper types are used for comparing or transferring dimensions.

  • Depth Gages

    Depth gages are used to measure of the depth of holes, cavities, or other component features.

  • Dimensional Indicators and Comparators

    Dimensional indicators and comparators measure where the linear movement of a precision spindle or probe is amplified.

  • Gage Blocks

    Gage blocks are manufactured to precise gagemaker tolerance grades for calibrating, checking, and setting fixed and comparative gages.

  • Height Gages

    Height gages are used for measuring the height of components or product features.

  • Snap Gages

    Snap gages are used in production settings where specific diametrical or thickness measurements must be repeated frequently with precision and accuracy.