SPI mold standards

plastic-injection-molding

SPI mold standards, SPI class 101 mold standard, SPI mold specifications

The following classifications are guidelines to be used in obtaining quotations and placing orders for uniform types of molds. It is our desire, through these classifications, to help eliminate confusion in the mold-quote process and increase customer satisfaction.

It is strongly recommended that mold drawings be obtained before construction is started on any injection mold. Even though parts may seem simple enough not to warrant a mold design, a drawing showing sizes and steel types will pay for itself in the event of mold damage.

As the applications of plastics become more sophisticated, so must mold designs. When designing a mold for a difficult part there are resources available to the moldmaker and molder to confirm the best mold design. For these designs it is recommended that a computer aided flow and/or cooling analysis be performed. These programs may help determine the best mold design, saving time and cost of design rework.

These classifications are for mold specifications only and in no way guarantee workmanship. It is very important that purchasers deal with vendors whose workmanship standards and reliability are well proven.

Mold life, because of variations in part design and molding conditions, cannot be guaranteed. This guide will attempt to give approximate cycles for each type of mold (excluding wear caused by material abrasion, poor mold maintenance and improper technique)

Maintenance is not the responsibility of the moldmaker. Normal maintenance, such as replacement of broken springs, broken ejector pins, worn rings or the rework of nicks and scratches should be borne by the molder. Mold rework costs should be closely considered when deciding which classification of mold is required.

This standard does not constitute a warranty or guarantee by the Society of the Plastics Industry, Inc., or its members for the classifications or specifications set forth herein.

  • Mold classification chart
  • SPI mold standards
  • SPI class 101 mold standards
  • SPI mold specifications
  • SPI mold classifications
  • SPI plastic tolerances
  • SPI injection molding tolerances
  • Injection molding tolerance standards
  • DIN 16901 tolerance chart
  • General tolerance table for plastic parts

SPI Mold Classifications & SPI Mold Standards

SPI Mold Classifications & SPI Mold Standards Society of the Plastic Industry Mold Building Standards The SPI Mold Classifications were developed by the U.S. Society of Plastic Engineers (SPE), with the intent of having a simplified definition of the type of injection tool for thermoplastics required for a set production need. These [...]

SPI Mold Unit Insert Standards

SPI Mold Unit Insert Standards CLASS 1 UNIT INSERT 1. Detailed mold design required. 2. Insert retainer to be uniform hardness of at least 280 BHN. 3. All molding and/or functional details are to be made of tool steel hardened to at least 48 R/C. 4. Slides must have wear plates. [...]

SPI Surface Finish Standards

SPI Surface Finish Standards The SPI is that Society of the Plastics Industry  sets standard for plastics industry in the United States that identifies the cosmetic quality of plastics, Upmold uses  the SPI standard to define finish of plastic injection molded parts. There are twelve grades of finishes specified by the SPI [...]

Plastic injection molding tolerance standards

Plastic injection molding tolerance standards Establishing tolerance with respect to product has significance importance on moldability and cost. It is recommended to indicate only critical dimensions with tolerances on a drawing. Depending on application, a division into three tolerance class can be made: Normal, Medium & Fine Cost of manufacture for Medium [...]

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