Date & Recycle Mark Inserts, Pins with Gas Vent
Product Categories
Gas Release Units
Round vent inserts, blow-type vacuum units, and vacuum generators for mold gas evacuation.
View 3 Products
Cavity Inserts for Gas Release
Round, slit, porous, and valve-spring vent cavity inserts with spacer accessories.
View 8 Products
Date Mark Inserts
Complete date marking systems: PL/plate exchange pin sets, double ring, adjustable, heat-resistant, plus tools.
View 20 Products
Recycle Mark Inserts
SPI recycling identification code pins — engraved and standard types for plastic packaging compliance.
View 2 ProductsFind the Right Solution for Your Mold
This category covers two distinct functions: gas venting to prevent molding defects, and marking inserts for date traceability and recycling compliance. Start by identifying your primary need:
Burn Marks / Trapped Air Problems
Seeing burn marks, short shots, or gas trapping in deep cavities? You need a gas venting power source — passive round inserts or active vacuum units.
Gas Vent Structural Components
Need cavity-mounted venting structures? Round, slit, or porous metal vent inserts with optional valve-spring assemblies and spacers.
Production Date Traceability
Need to stamp production dates on molded parts? Choose from PL-side, plate-side, double ring, adjustable, or heat-resistant date mark pin sets.
Recycling Symbol Compliance
Plastic packaging requires SPI recycling identification codes? Engraved or standard recycle mark pins for regulatory compliance.
Selection tip: Start with the problem you're solving — gas traps need venting inserts, traceability needs date marks, compliance needs recycling marks. For a broader overview, see our Mold Gas Venting Fundamentals guide.
Understanding Mold Gas Venting & Part Marking
Two critical but often overlooked aspects of injection mold design: proper gas evacuation and regulatory part marking.
Why Molds Need Gas Venting
During injection molding, air trapped in the cavity and volatile gases released from heated resin must escape before the melt front seals the parting line. Without adequate venting:
- Burn marks (diesel effect) — Compressed trapped air ignites, charring the resin surface
- Short shots — Gas pressure resists resin flow, leaving unfilled sections
- Weld line weakness — Air pockets at flow fronts reduce part strength
- Surface defects — Splay marks, silver streaks from trapped volatiles
Gas venting solutions range from passive round inserts (simple, maintenance-free) to active vacuum systems (for deep cavities where passive venting is insufficient).
Date Marking & Recycling Compliance
Most injection-molded parts require production traceability. Date mark inserts stamp the manufacturing date (year/month) directly onto molded parts during the forming process, eliminating post-mold marking. Recycling mark pins apply SPI resin identification codes (♳♴♵♶♷♸♹) required by packaging regulations in the EU, North America, and Asia-Pacific markets.
Engineering note: Gas venting and part marking serve completely different functions but often share the same mold insert pocket. For regulatory requirements across regions, see our Injection Mold Marking Standards Guide.
Troubleshoot a Molding Problem
Identify the symptom you're experiencing to find the right product solution:
| Problem | Root Cause | Solution |
|---|---|---|
| Burn marks / diesel marks on part surface | Trapped air compresses and ignites during filling | Gas Vent Round Inserts or Porous Vent Inserts |
| Short shots in deep cavities | Gas pressure blocks resin flow in blind holes | Vacuum Unit for Gas Venting (active evacuation) |
| Incomplete venting despite parting line vents | Complex cavity geometry traps gas away from parting line | Slit Vent Cavity Insert Blocks (diffusion-bonded) |
| Date code illegible after production run | Date mark pin wear from abrasive resin or high temp | Heat-Resistant Date Mark Inserts |
| Cannot update production date without disassembling mold | Using fixed engraving instead of exchangeable inserts | PL-Side Exchange Date Mark Pin Sets |
| Missing SPI recycling symbol on packaged product | No marking insert installed in mold cavity | Recycle Mark Pins |
About Date & Recycle Mark Inserts, Pins with Gas Vent
This category combines two essential injection mold component families: gas venting systems that eliminate trapped-air defects (burn marks, short shots, weld line failures), and marking inserts for production date traceability and recycling compliance. We supply passive vent inserts (round, slit, porous metal), active vacuum units, complete date marking pin sets with exchangeable rings and arrows, and SPI recycling code pins. All products are compatible with DME, HASCO, and MISUMI mold bases.
Industry Applications
See how these products solve real engineering challenges across industries:
Automotive Connector & Housing Molds
Tight cavity geometries in automotive connectors trap gas during high-speed injection. Gas vent inserts prevent burn marks on visible surfaces, while date mark pins ensure production traceability for IATF 16949 compliance.
Why these products fit: Gas vent round inserts provide precision-machined channels sized for engineering resin viscosity. Stainless steel construction resists corrosion from glass-filled PA and PBT outgas. Date mark pin sets with PL-side exchange enable shift-by-shift date code updates without mold disassembly — meeting IATF 16949 audit requirements.
Medical Device Enclosure Molding
Zero-defect requirements in medical housings demand complete gas evacuation. Vacuum-assisted venting eliminates short shots in deep-cavity parts, and date marking supports ISO 13485 lot traceability.
Why these products fit: Vacuum generators create pre-injection cavity negative pressure, ensuring complete fill in deep syringe barrel and diagnostic cartridge geometries. Heat-resistant date mark inserts withstand PPS/PEEK processing temperatures above 200°C while maintaining legible lot codes for ISO 13485 device history records.
Food & Consumer Packaging Molds
High-volume packaging molds require fast cycle times with no gas trapping. Recycle mark pins meet SPI/EU labeling regulations, while porous vent inserts handle thin-wall gas evacuation.
Why these products fit: Porous sintered metal cavity inserts provide full-perimeter micro-venting for thin-wall PP/PE containers without flash. SPI-standard recycle mark pins meet EU Directive 94/62/EC and North American labeling requirements, with engraved variants for permanent legibility through millions of cycles.
Frequently Asked Questions
What causes burn marks and short shots in injection molding, and how does gas venting solve these problems?+
Are date marks and recycling symbols standard practice in injection molding?+
Can gas vent inserts and date mark inserts be installed in the same mold?+
Related Product Categories
Engineering Resources
Gas Venting vs. Date Marking Inserts: Key Differences Explained
Understand the two product families in this category and which one solves your problem.
Why Injection Mold Burn Marks Occur (And How Gas Venting Fixes Them)
Step-by-step diagnosis and gas venting solutions for common injection molding defects.
Mold Marking Regulations by Region: Date Codes & Recycling
Date codes and recycling symbol requirements across EU, North America, and Asia.
Need a Custom Quote?
Send your specifications — vent diameter, marking type, mold temperature range — and receive a quote. MOQ: 1 piece. Custom dimensions available.