Custom plastic plungers

Machining inquiries for specified plunger dimensions, surfaces and end features.

CDS machines engineered plastics from customer drawings and supports existing-part documentation for replacements. Send the plunger definition or available sample records to confirm the particular material, geometry and manufacturing scope.

Photography plannedPlunger · full working length
The outside diameter, working length and end features define the plunger to be machined.

Outside diameter, length and end details

A plunger's working surface passes through stationary sealing or packing. Its drawing specifies the cylindrical surface and end features to be machined.

For a body carrying a seal through a bore, see plastic pistons. For a valve element with raised lands and grooves, see valve spools.

Working surface, length and end features
  1. Working surface has a specified diameter, form and finish.
  2. Working length identifies the cylindrical portion on the part drawing.
  3. End features follow the required connection geometry.

Side view of one example plunger. Shoulders, transitions and ends are separately dimensioned. No packing, housing, installed fit or motion is shown.

Working diameter and length
Give the outside diameter, cylindrical working length and overall length. Identify specified roundness, straightness, tolerances and finish on the relevant surface.
Shoulders and transitions
Steps, radii, tapers and end faces have their own dimensions and locations. Distinguish these features from wear or damage on a sample.
Connection features
Threads, bores, holes, flats and other end details form part of the plunger drawing. Separate packing, seals and assembly hardware require their own supply confirmation.

CDS provides CNC turning of engineered plastics. The specified grade, form, surface finish and tolerances determine the machining requirements to be confirmed for your part.

Replacement plungers from existing-part records

A physical plunger, older print or equipment part record can start a replacement request when documentation is incomplete.

Separate original features from wear

Reverse engineering records the existing component for manufacture. A worn diameter, scored surface, distorted section or damaged end may no longer show its original form.

Mark intact areas and provide known dimensions, an unworn spare or older drawing where available. Unknown dimensions, finish and material requirements need clarification before machining.

Updated drawings and repeat orders

A customer-specified change needs an updated part drawing and revision. For repeat work, identify the current plunger number and any previous CDS order.

Specified grade and surface finish

Provide the complete plastic designation, including any controlled brand, filler and permitted substitution. CDS confirms availability and machining scope for that material and geometry.

A surface-finish callout must identify the surface and requirement on the drawing. A nominal outside diameter alone does not describe the specified form or finish of the plunger.

Material records for replacements

Use an existing material record where available; appearance alone cannot identify the exact grade. If PTFE is specified, provide its complete compound callout.

Required order documentation

List material, food-contact, traceability, inspection or other required documents for confirmation. Any special detectable-grade requirement needs separate availability and documentation confirmation for the actual part.

Request a plunger machining quote

Start with a drawing, specification, dimensioned sketch or details of an available sample. Identify the plunger itself and the current revision.

Plunger definition

Outside diameter, working and overall lengths, shoulders and end features. Include the specified form, tolerances, finish and reliable dimensions for a worn sample.

Material and supply

Exact plastic grade, required brand or filler, permitted substitutions and required records. Identify separately requested items and any unresolved part requirements.

Order details

Quantity now, repeat quantities, requested timing and previous CDS order reference. The particular machining scope and timing are confirmed for the quotation.

Contact CDS before arranging to send a physical plunger.

Start with a plunger sample

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