• Virtually Impervious to Water
  Polyurethanes remain stable for very long periods even when immersed in water at 50°C(1 22°F). In fact they are successfully used in water-lubricated bearings, where even slight increases in volume would cause seizing.
• Good Insulators for Heat, Cold and Electricity
  Most polyurethanes are excellent electrical insulators and are used extensively in potting and encapsulating applications. Additionally, no other material offers an R value higher than some types of polyurethane foam.
• Highly Resistant to Impact
  Polyurethanes are ideal for parts that have to stand up to high impact or repeated impingement.
• Resistant to Oil, Grease and Chemicals
  Polyurethanes resist a much wider range of these sub stances than even rubbers and plastics.
• Bonds to Wood, Metals and Most Plastics
  Under controlled conditions during the molding process, polyurethanes can be bonded to a wide variety of materials. Bond strengths on these substrates are often stronger than the polyurethane itself, and certainly several times stronger than similar rubber-to-substrate bonds.
• Sound and Vibration Reduction
  Special polyurethane formulations are available for sounddeadening and anti-vibration applications.

Gator System Dunnage (CBU-78/B)

The US Navy needed a lightweight, interlocking dunnage assembly for the Gator System. The parts were up to five feet in length and were designed to keep explosives and electronics correctly aligned within the munitions housing.

The Solution: Hennis Enterprises molded the entire assembly in high density, rigid foam. All the parts were made to the following military specifications:

• Conform to tolerances up to .010 inch and withstand a compression of 400psi.

• Remain dimensionally stable through a wide range of acceleration, altitude (air pressure) and temperature.

• Non-conductive to electricity.

In addition to these basic requirements, one section of dunnage also included a 30 Ib steel rod encased in the foam for balanced weight distribution. The Gator System dunnage was produced under contract with the US Navy, and delivered ahead of schedule.

Floating Mercury Switch

A leading manufacturer of marine equipment needed a more reliable floating mercury switch for use on an automatic bilge pump. The existing switch was made of foam, but crudely molded and badly formulated causing structural flaws and corrosion of the electrical leads.

The Solution: Hennis Enterprises redesigned the part. The switch and electrical leads were potted in an elastomer, making them heavily resistant to oils, fuels and salt water. Potting methods were then integrated with the mold design, ensuring precise placement of the mercury switch inside the finished part.

Finally Hennis Enterprises developed a multicavity mold for mass production of the switch, reducing the unit cost by over 50%, compared to the original defective switches.

Hennis Enterprises has been a leader in polyurethane product design and manufacture since 1975. We provide support in the design and engineering phase of a project to ensure your structural requirements are met in the most cost-efficient way. After consultation with your project team we develop the chemistry for a custom foam or elastomer with the desired physical properties and produce the requisite tools and molds. From conception to finished part, turnaround time with polyurethane is extremely short in comparison to other alternatives.

Polyurethane is tremendously versatile, but strict process control is the only guarantee of superior performance in the finished product. At Hennis Enterprises we can accurately regulate material and mold temperatures throughout the manufacturing process, we can dispense components to plus or minus one gram and we have achieved specified tolerances as low as .010 inch.

Whether you need just a few R&D samples or a full scale production run, we have the experience and capacity to provide low cost, light-weight, precision solutions to your toughest engineering problems.

Military & Aerospace Applications

Aerospace and military engineers are increasingly using polyurethane, especially for encapsulation, insulation, flotation and dunnage. Its versatility and high strength-to-weight ratio make it the natural choice for many problem applications, and in most cases polyurethane is also considerably lower in cost. The key is in the manufacturing process, where low-pressure, liquid pouring replaces injection molding, reducing mold costs typically by a factor of ten!

Hennis Enterprises excels in mold design and construction to meet military specifications, from prototype tooling, to multi-cavity, mass production molds. All phases of our manufacturing cycle, from procurement through shipment, are controlled under a Quality Control System.

We currently manufacture parts for the Navy, Air Force and several primary military contractors.

Please call us, perhaps we can lend our expertise to your next project.