Injection Mold Standards - Plastics PUR-TOOL-PRO-010 1.0 Purpose

The purpose of this standard is to establish and maintain a standard of quality and consistency in the concept, design, and build of production tooling for Herman Miller, Inc. while ensuring safety, serviceability, maintainability, and uniform tooling procedures. It is not intended to limit creativity in the design and build of tooling.

2.0 Scope

This standard is applicable for all new or rebuilt production injection mold tooling purchased or manufactured for Herman Miller, Inc. It should be used as a guideline for the concept, design, and manufacture of such tooling.

3.0 Reference Documents

 PUR-TOOL-PRO-006 Supplier Tooling Guidelines  PUR-TOOL-PRO-010 Injection Mold Design Review Checklist  PD-ENG-008 Dimensional Verification Guidelines  PD-ENG-019 Production Part Marking for Recycling  PUR-TOOL-PRO-003 Tooling Purchase Order Generation  CORP 4.2 Production Part Approval Process

4.0 Safety Considerations

4.1. All tooling must meet OSHA, MIOSHA and all other applicable local, state, and federal guidelines. 4.2. All tooling must be designed to incorporate ergonomic considerations for operation, changeover and maintenance.

5.0 General Guidelines

5.1. These standards are meant to supplement supplier provided standards for tool quality and performance. 5.2. These standards supersede like items from supplier provided standards. 5.3. These standards do not relieve the supplier and tool builder from the responsibility to produce parts to the Herman Miller, Inc. quality and reliability requirements for the agreed upon tool life. 5.4. All tooling should meet the guidelines defined in document PUR-TOOL-PRO-006 Supplier Tooling Guidelines. 5.5. Tooling specifications are to be submitted per PUR-TOOL-PRO-003 to the Tool Engineering Group prior to release. 5.6. These tooling standards may not apply to tooling that is built for the intent of pre- production, pilot, or low volume tooling. The supplier should engage the HMI

Revised: 9/22/11 page 1 of 8 Injection Mold Standards - Plastics PUR-TOOL-PRO-010 Tooling Engineer to approve any deviation not adhering to the tooling standard items. 5.7. The supplier must review with the HMI Tooling Engineer to gain approval of any tooling standards not deemed necessary due to quality, reliability, or cost issues. 5.8. Parting lines, gates, ejector pin locations, texture, and draft considerations must be reviewed and approved by Herman Miller, Inc.

6.0 Tool Quoting and Acquisition

6.1. All tool builders used by Herman Miller, Inc. will receive a copy of the Injection Mold Standard with all reference documents at the time of the quote request. 6.2. The parts supplier to Herman Miller, Inc must identify the tool life at the time of quote. The tool life should be confirmed prior to release to production between the supplier and Herman Miller Tooling Engineer. This will identify any exceptions to the tool.

7.0 Tool Concept and Design – General

7.1. Herman Miller, Inc. practices a team approach to the design and build of all tooling. A core team of Herman Miller, Inc. employees will meet with the tool builder during the conceptual and design stages of the product, unless Herman Miller deems it unnecessary. 7.2. As part of the Final Design Review prior to approval to cut steel, design issues such as parting line, gate and ejector pin locations, texture and draft should all be reviewed in advance and approved by HMI before approval to cut steel. 7.3. The tool builder is to follow the tool design concepts and production methods identified at the time of the quote. Suggestions for improvements are encouraged and will be open for discussion. 7.4. The tool builder is to submit a written document to Herman Miller, Inc. identifying all requested design changes. A final design review with Herman Miller, Inc. may be required before manufacture of the remaining components begins. 7.5. An FMEA (failure mode and effect analysis) may be required after final design review and prior to release for build This will be done at the discretion of Herman Miller. 7.6. Weak steel conditions should be reviewed and analized prior to release for build. 7.7. All tool designs are to be formatted to a DWG or DXF format. 7.8. A final design including bill of materials, detailed CAD drawings of perishable details, and a recommended spare parts list must be available to Herman Miller, Inc. upon request. 7.9. All wire EDM math data used to create replaceable details must be furnished to the customer upon shipment of the die and must be available to Herman Miller upon request. The data must represent the details to the latest tool revision consistent with the tool at PPAP run-off. Final payment should be withheld until this tooling data is supplied to HMI. 7.10. The customer of the tool will advise the tool builder on maximum die weight.

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8.0 Tool Build Requirements

8.1. General Construction

8.1.1. All molds are to be designed to minimize press size. 8.1.2. All molds are to be designed with DME, PCS, or other standard manufacturers for common guide pins, bushings, sprue bushings, ejector pins, core pins, ejector sleeves, etc. 8.1.3. Tool steels are to be stress relieved after machining.

8.2. Cooling

8.2.1. Water line disconnects are to be recessed flush with the mold. MUD units may be the exception. 8.2.2. Water line diameters must be consistent with fittings used to minimize pressure drop. 8.2.3. Ports must be sized properly to accommodate baffles while minimizing pressure drop. 8.2.4. Main cavity and core areas are to have symmetrically balanced and independent cooling circuits whenever possible. 8.2.5. All water line connections must be located so the mold clamps are not inhibited during the mold set-up. 8.2.6. All lines must be pressure checked to 90-psig minimum.

8.3. Cores and Cavities

8.3.1. Inserts should be designed to only assemble one way. 8.3.2. All critical wear, venting areas, fragile cores and gates in the cavity and core areas should be evaluated for insert construction or the future addition of inserts to minimize repair cost and time. Thin wall and rib areas should also be evaluated. Cooling of the tool should not be compromised as a result. 8.3.3. Mold parting surfaces outside the shut-off areas are to allow a minimum of 0.020” clearance when the mold is closed. 8.3.4. Rising cores or lifters are to be on rod guides with bronze bushings where applicable. 8.3.5. Welding is not permitted in cavities of new tooling, unless a change is required because of an engineering part design change. The HMI tooling engineer must approve the welding. The tool builder is responsible for correctly stress relieving the steel (i.e., preheating, welding, and post heating) as required to ensure the welded steel wears similarly to the non- welded steel. 8.3.6. All core pins having the same size cavity dimensions and geometry shall have the same body and head dimensions so as to be interchangeable.

Revised: 9/22/11 page 3 of 8 Injection Mold Standards - Plastics PUR-TOOL-PRO-010 8.3.7. All cored bosses are to be cored with a standard core pin and ejector sleeves where possible. 8.3.8. Interchangeable core pins and bosses are to be keyed and numbered to identify position.

8.4. Cylinders and Valve Gates

8.4.1. All switches and plugs are to be mounted sub-surface to the mold base where possible and on a non-operator side. 8.4.2. Cylinders, valve gates, and related switches/timers outside of the mold base are to be protected with standoffs, frames, or pillars. 8.4.3. NPT threads are required for all hydraulic connections. 8.4.4. Valve gates are to be mounted on a non-operator side of the mold. Connections should also be on a non-operator side or top of the mold. 8.4.5. Parker hydraulic cylinders and fittings are preferred. 8.4.6. All cylinders are to have limit switches to sense when the cylinder is set or pulled. Additional switches must be used to adequately protect the tool in the case of multiple cylinders per core sequence. 8.4.7. All cylinders are to be accessible for easy maintenance, preferably without the need to dismantle the mold.

8.5. Ejectors, Lifters and Knockouts

8.5.1. Ejector plates are to be spring loaded when applicable. 8.5.2. Venting down ejector pins in deep part features should be considered where applicable. 8.5.3. All ejector pins and blades should be guided with commercial leader pins and bronze ejector plate bushings. Avoid modified pins and sleeves for ease of replacement. The use of non-standard pins should be reviewed for necessity and must include a plan for replacement spare parts. 8.5.4. Positive return mechanisms are required whenever slide cores extend over ejector pins. 8.5.5. Positive returns should be used for lifters where possible. 8.5.6. Accelerated knockouts are to be a positive return type with no springs 8.5.7. The ejector stroke is to be a minimum ¼” longer than the part depth. 8.5.8. Forward stops used for ejector plates should be located in line with knockout holes. 8.5.9. All ejector pinholes must be sized to ensure smooth flash-free operation. 8.5.10. All ejector pinholes are to be relieved so the bearing surface is ¾” minimum. 8.5.11. Round pins less than 3/32” diameter are not to be used without specific approval. 8.5.12. Rising cores or lifters are to be on rod guides with bronze bushings where applicable. 8.5.13. Lifter rods are to be threaded into the lifter and must be secured in the ejector plate to prevent rotation.

4 Injection Mold Standards - Plastics PUR-TOOL-PRO-010 8.5.14. A retainer plate is needed behind the ejector housing when using sleeve ejectors.

8.6. Electrical

8.6.1. All wiring and connectors for hot runner systems are to be flush mounted with the mold surface and covered with screw on cover plates where possible. The wiring and connectors must be protected when they cannot be flush mounted. 8.6.2. All wires, connectors and terminals are to be high temperature components rated at 800 deg. F minimum sustained operating level. 8.6.3. All wiring for hot runners should be channeled to the non-operator side or the top of the mold. 8.6.4. There are to be no rough or sharp edges on any wiring channels. 8.6.5. Wire channel clips are to be utilized to protect all hot runner wires. 8.6.6. The sprue bushing/locator should protect the heated sprue from leakage or over-purge. 8.6.7. The manifold heater shall be sized and installed so the system is capable of maintaining temperatures at the proper operating level utilizing 75% of the heaters. 8.6.8. Manifolds and nozzles are to be heated externally to prevent obstructions in material flow.

8.7. Gates and Runners

8.7.1. Runners and gates must be designed to facilitate a balanced fill pattern. 8.7.2. Subgates must be designed with one ejector pin on the part surface near the gate and a minimum of one ejector pin on the runner. 8.7.3. All gates are to be free of machining marks. 8.7.4. All gate to runner transitions are to be radiused to minimize pressure drops and improve flow. 8.7.5. All sprue puller pins are to be undercut. 8.7.6. Automatic degating should be used when possible. 8.7.7. Gating details must meet the Herman Miller, Inc. part drawing requirements. Herman Miller, Inc. must approve the gating details.

8.8. Mold Bases

8.8.1. All standard mold bases must have centered and balanced eyebolt holes to meet safety requirements. 8.8.2. The tool must have the required number of safety straps with 90-degree rotation so they can be stored on the tool when in the press. 8.8.3. Leader pins are to be mounted in the cover half of the mold.

Revised: 9/22/11 page 5 of 8 Injection Mold Standards - Plastics PUR-TOOL-PRO-010 8.8.4. Leader pins must engage guide sleeves before any part of the core enters the cavity (1/2” pre-engagement minimum is preferable). 8.8.5. Mold base edges must be broken to minimize the potential to damage the edges, which could keep the die from locating tight against the press platen. 8.8.6. All molds should have a lead-in style locating ring. 8.8.7. All molds designed with core and cavity registration (where the parting line is within the part geometry) or thin wall parts must use taper locks or side die locks to maintain location. Parting line locks should be used on all tools, especially where vertical shut-offs are present. 8.8.8. Clamp slots should be on the side of the tooling as mounted in the run position. 8.8.9. Vertical shut-offs are not preferable. This is to be discussed in the design review if vertical shut-offs are necessary. 8.8.10. Molds are to have guided ejection systems where applicable.

8.9. MUD Units

8.9.1. Interchangeable inserts should be designed to allow for removal while the mold is in the press. 8.9.2. All MUD units are to have one centered and balanced eyebolt hole on the top of each half of the mold. 8.9.3. All MUD units must have positive stops to prevent the ejector plate from being pulled out of the cavity. 8.9.4. Inserts to be properly located (alignment) and held in place to maintain parting lines.

8.10. Part Identification

8.10.1. Part identification must be included per the Herman Miller, Inc. part print requirements. This should include the cavity number and material designation where applicable. Reference SI-351 (Procedure for Marking Plastic Parts for Material Designation) for material designation. 8.10.2. Part identification must be applied in locations defined on the Herman Miller, Inc. part print. 8.10.3. In addition to Part identification requirements listed above, in cases where there is more than one tool at one or more suppliers, it is Herman Miller policy to identify each part with the Herman Miller Asset number as well as the part number. This is necessary for part tracability to the tool/supplier source. 8.10.3.1.Normal accepted practice is to use the same identification method as the part number but the asset number will be located directly under the part number in the same font or one type set smaller. 8.10.3.2.The Asset number identification is to be the asset number on the purchase order authorizing the tool build.

6 Injection Mold Standards - Plastics PUR-TOOL-PRO-010 8.10.3.3.Where multiple tools are in production, this is a requirement. If part geometry dictates part and asset identification is impossible, written authorization from a Herman Miller Tooling Engineer is required.

8.11. Program Requirements

8.11.1. Manifold diagrams are required for hot runner systems. 8.11.2. Thermocouple locations must be defined on drawings. 8.11.3. Water flow drawings must be defined.

8.12. Slides

8.12.1. Detent details are to be on slide mechanisms, as applicable, to ensure positive location prior to the mold closing. 8.12.2. Laminate plates are to be used for glide surfaces in addition to steel gibs for guiding. 8.12.3. Standard (non-graphite impregnated) laminate plates are preferred. 8.12.4. All areas subject to high wear must have provisions for lubrication. 8.12.5. Slide components are to be purchased and readily available components such as Superior Die set slide-lock or DME slide retainers. 8.12.6. Slides should be removable with the mold in the press and with the slide in any position where possible. 8.12.7. Slides should be gibbed.

8.13. Sprues

8.13.1. Offset sprue bushings are not preferred. 8.13.2. Sprue bushings are to be keyed to prevent turning, unless no contour is present.

8.14. Tool Identification

8.14.1. All mold components are to be labeled to facilitate ease of assembly and disassembly. 8.14.2. All air, vacuum, or water lines are to be identified for line type and serialized to indicate the “in” and “out” ports for each circuit (“IN-1 and OUT-1”). 8.14.3. Mold bases are to stamped with the following minimum tool information:  HMI asset number  HMI part/drawing number  Production release date  Tool builder and job number  Supplier tool/job number  TOP of mold

Revised: 9/22/11 page 7 of 8 Injection Mold Standards - Plastics PUR-TOOL-PRO-010  Mold weight  Shrinkage MUD Inserts must be identified with the HMI asset number and HMI part number at a minimum. The remaining tool information is to be added as applicable. If MUD Unit is owned by HMI, it should also be stamped complete as stated above. 8.14.4. All identification information is to be stamped on the tool. Tags can also be used to improve readability, but they must be used in addition to the stamping. 8.14.5. All steel is to be stamped with the steel type and hardness, if applicable, in a non-critical location.

8.15. Miscellaneous

8.15.1. Include a 2" square test plaque with texture and 2" square test plaque without texture side-by-side in an area near the parting line. 8.15.1.1.1. The plaque with texture is to test gloss of texture with Armoloy coating. The plaque without texture is to test for Armoloy coating thickness. 8.15.2. Non-resettable counters should be included on all tools to track tool life. 8.15.3. Counters should be mounted so they do not get damaged during handling. 8.15.4. Counters must be sufficiently insulated to prevent heat damage. 8.15.5. Pry slots are to be provided on all mold-parting lines to permit ease of disassembly.

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