LDPE Specifications | Sizes, Tolerances & Standards

LDPE sheet and rod are available in a broad range of standard sizes with tight thickness and diameter tolerances. The governing material standard for LDPE stock shapes is ASTM D4976 (Standard Specification for Polyethylene Plastics Molding and Extrusion Materials), with dimensional tolerances following industry norms established for extruded and compression-molded polyethylene stock. This page covers standard sizes, tolerances, available standards, and weight reference data for purchasing and fabrication planning.

At a Glance

• Sheet sizes: Standard 48" × 96"; custom widths available
• Sheet thickness: 1/32" through 4" — with thickness tolerances of ±5% to ±10% depending on gauge
• Rod diameters: 1/4" through 6" standard; larger diameters by inquiry
• Material standard: ASTM D4976; FDA 21 CFR 177.1520 for food-contact grades
• Colors stocked: Natural, black, white in most sheet thicknesses
• Lead time: Standard sizes typically ship same-day or next-day from inventory

Applicable Standards and Specifications

Material Standards

LDPE stock shapes produced for food-contact service are manufactured from resin that meets FDA 21 CFR 177.1520 criteria. The part itself must still be evaluated for its specific use condition — contact sales for lot documentation and certification letters when required.

Testing and Quality

Material test reports (MTRs) documenting density, melt flow index, and tensile properties are available with order. For pharmaceutical and food industry orders requiring full traceability, specify MTR requirements at the time of purchase. RoHS compliance statements are available on request.

LDPE Sheet Specifications

Standard Sheet Size

The industry standard sheet format is 48 inches × 96 inches (4 ft × 8 ft). This format is compatible with standard CNC router and waterjet table dimensions, and allows efficient material utilization for most cut-to-size programs.

Standard Thicknesses — Sheet

Weight calculated at density 0.920 g/cc (57.4 lb/ft³).

Sheet Color Availability

Custom colors and opaque formulations are available in minimum-order quantities. Contact the sales team for details.

LDPE Rod Specifications

Standard Rod Diameters

Standard rod length is 10 feet, cut from continuous extrusion. Cut-to-length service is available; minimum order varies by diameter.

Rod Straightness Tolerance

Extruded LDPE rod is softer than HDPE or acetal rod and is more susceptible to warpage in storage. Standard straightness tolerance is 1/8" per foot of length. For applications requiring straighter stock, specify precision-straightened rod or plan to machine from short cut sections.

Thermal Expansion Reference

LDPE has a high coefficient of linear thermal expansion (CLTE) at 11 × 10⁻⁵ in/in/°F. For parts assembled to steel or aluminum structures, design with clearance to accommodate differential expansion.

These values are for reference — use actual service temperature range and part dimension in your thermal expansion calculation.

Machining Blank Sizing

When ordering LDPE to machine into a finished part, add stock allowance for:

• Turning (rod): Oversize by 1/4" to 3/8" on diameter for OD turning and facing
• Milling (sheet): Oversize by 1/8" to 1/4" per edge for fixturing and surfacing
• Thermal stress relief: LDPE extrusions retain some stress from the production process. For tight-tolerance finished parts, rough machine and allow 24 hours before finish cuts
• Warpage: Thin sheet sections can warp when large amounts of material are removed; machine symmetrically and support flatly

See the LDPE machining guide for detailed speeds, feeds, and tooling recommendations.

Comparing LDPE and HDPE Dimensional Standards

LDPE and HDPE stock shapes follow the same dimensional standards and are generally available in the same thicknesses and diameters. The key dimensional difference in practice is rod straightness: HDPE rod is stiffer and holds straightness better in long lengths, while LDPE rod in diameters below 1" can bow appreciably in 10-foot standard lengths.

For buyers migrating a design from LDPE to HDPE — typically to gain stiffness or higher temperature rating — the same cut sizes and stock dimensions apply directly. No tooling or fixture changes are required.

See HDPE vs. LDPE for a full property comparison.

Request LDPE by Size

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