PDI Molding has the specialized skills for injection molding precision parts with complex geometries. We worked in close collaboration with a client in the construction equipment industry on the design and manufacture of the pump housing highlighted here.

Designed for use on a power hydraulic filter, we recommended carbon and glass reinforced, heat-stabilized polyamide 6/6 as the material of construction due to its strength, dimensional stability and resistance to both heat and abrasion for this under-the-hood application. We designed the mold with two independent unscrewing cores; the first creates a 7/16-20UNF thread with mold in fully closed position, while the second forms a custom 2 61/64 -0.118 thread with the mold in fully open position. Our all-electric 310 ton injection molding press incorporates advanced control features, and in combination with our precision built die, we were able to uphold ±0.004” tolerances. Final operations consisted of inserting the aluminum tube. Quality assurance procedures involved both dimensional and surface inspections as well as functional fit tests.

When completed, the pump housing measured 9-7/8” to 11-¾” in length x 5-½” in width and featured a textured SPI-B3 finish on all sealing surfaces. We continue to produce this part for the customer in various quantities with typical turnaround time of one or two weeks, depending on order size.

To learn more about this project or our injection molding capabilities, contact us today.

PDI Molding provides precision injection molding of plastic component with complex geometry. For this project we have design mold with two independent unscrewing cores

We worked with customer throughout the design, development and material selection stage to ensure their design is moldable.

Each part is molded utilizing horizontal all electric 310 ton injection molding machine with special option to unscrew first core that creates 7/16-20UNF thread with mold fully in close position and the second unscrewing core at mold fully open position for the custom 2 61/64 -0.118 thread. Parts are molded with tolerances of ±0.004 inch.

Injection Molding of Pump Housing Project Highlights

Project Name & Description

This specialized pump housing is used on power hydraulic filter in construction equipment.

Capabilities Applied/Processes


  • Product development & Design
  • Material selection
  • Mold Design

Injection molding
Secondary operation, inserting aluminum insert-tube into each part

Equipment Used to Manufacture Part

Horizontal all electric 310 ton injection molding machine

Overall Part Dimensions

Length: 11 ¾” and 9 7/8″
Width: 5 ½”

Tightest Tolerances


Material Used

Carbon & Glass reinforced Polyamide 6/6 Heat Stabilized

Mold Texture

Chemically Etch Texture , 0.001 deep & SPI-B3 on sealing surfaces

Industry for Use

Construction equipment

In Process Testing/Inspection Performed

Customer specified dimensional inspection and functional fit checks dimension and cosmetic inspection of each part


Up to 10,000/yr

Delivery/Turnaround Time

1 to 2 Weeks typical

Delivery Location

Plant located in Mid Atlantic /USA

Standards Met

Customer Specification