One of North America’s Largest Rotational Molding Machines

Manufacturing the next generation of chemical storage tanks in Garrett, Indiana. Reduced lead times, state-of-the-art PLC precision, and unmatched capacity.

Investing in High-Capacity Chemical Tank Manufacturing

In the chemical storage tank industry, a dangerous trend is emerging. Manufacturers are cutting costs by thinning out tank walls, hoping they last just long enough to pass warranty.

At Assmann Corporation, we refuse to compromise. We have completed the installation of a new High-Capacity Bi-Axial Rotational Molding Machine, one of the largest of its kind in North America.

This investment allows us to produce chemical storage tanks up to 12,500 Gallon capacity. Assmann Corporation’s storage tanks are produced to ASTM D 1998 standards which are precise, rigorous and the industry benchmark for manufacturing and testing above ground, vertical polyethylene storage tanks. Our process follows these standards, never deviating or making exceptions.

Advanced Bi-Axial Rotational Molding Technology

Unlike injection molding or blow molding, rotational molding relies on heat and bi-axial rotation to create hollow, seamless vessels.

How Bi-Axial Rotation Works

Our new machine rotates the mold on two distinct axes simultaneously:

  1. Our Oven acts as the Vertical Axis: Unique to the industry, our oven tubles end over end allowing for uniform dispersion of the polyethylene resin throughout the mold. Tumbles the mold end-over-end.
  2. Our Oven carts act as the Horizontal Axis: Our individual mold carts roll the rotational mold clockwise and counter clockwise with very specific timing again ensuring uniform dispersion of the polyethylene material.

This dual-motion ensures that the Polyethylene flows evenly over every square inch of the mold, creating absolute Uniform Wall Thickness.

State-of-the-Art PLC Controls Older machines rely on manual timing. Our new system features advanced PLC (Programmable Logic Controller) technology that monitors:

  1. Internal mold air temperature
  2. Exact rotation ratios.
  3. Oven dwell time.

This digital precision ensures that every tank we produce is identical to the last, eliminating the tapered walls common in competitor tanks.

Transforming your business through creative process

Reducing Lead Times with Production Redundancy

One of the biggest challenges in industrial tank procurement is lead time. Large-scale projects cannot afford delays.

By installing this high-capacity machine, Assmann Corporation has established critical manufacturing redundancy.

  • Faster Delivery: We have doubled our capacity for large-scale vessels, allowing us to
    reduce lead times significantly
  • Reliability: With multiple machines capable of running large molds, maintenance schedules never impact your project delivery date
  • Fuel Efficiency: New technology reduces our carbon footprint and improves energy
    efficiency per cycle.

Optimized for Cross-Linked Polyethylene (XLPE) Tanks

A chemical storage tank is only as good as its molecular bond. This machine is specifically tuned to process Cross-Linked Polyethylene (XLPE).

Why XLPE Matters Standard linear polyethylene can separate under stress. XLPE creates a 3D molecular net that offers superior resistance to:

  • Aggressive oxidizers
  • Stress cracking.
  • Hydrostatic pressure.

Our machine’s PLC controls hit the perfect “gel point” every time, ensuring the cross-linking reaction is complete and the tank is fully cured for maximum durability

Applications for High-Capacity Rotational Molding

This new machine allows us to serve a diverse range of critical industries that require bulk liquid storage.

  • Municipal Water Treatment: Storage of Sodium Hypochlorite (Bleach), Alum, Ferric Chloride, and Fluoride.
  • Industrial Chemical Processing: Bulk storage of Hydrochloric Acid, Sulfuric Acid, and Sodium Hydroxide (Caustic Soda).
  • Food & Beverage Production: We can mold FDA-compliant Linear Polyethylene vessels for brine, vinegar, oils, and ingredient storage.
  • Deicing & Transportation: Storage of Magnesium Chloride and Calcium Chloride for winter road maintenance.

Engineered for ISO 9001 Quality Standards

Uniform Wall Thickness

The precision of this rotational molding machine eliminates process related stresses. Manufacturing tanks with uniform wall thickness eliminates “steps” or “tapered wall thickness” that lead to premature tank failure. Our tanks maintain consistent thickness from the tank bottom knuckle to the top dome, meeting and exceed ASTM D 1998 standards. This coupled with our ISO 9001 certification places Assmann Corporation as the number one manufacturer of Industrial Chemical Storage Tanks and Containers.

Employee Safety

Assmann Corporation believes in the safety of our employees and the safety of those around us. Modernizing our equipment allowed us to review our current safety practices and improve features that create a better work environment for our employees. Our equipment has fall protection, light curtains and some of the most modern technology available to protect our employees, who we view as our family.

Watch the Assmann Manufacturing Process

See our High-Capacity Rotational Molding Machine in action and learn why we invest in the largest equipment in North America to reduce lead times

Frequently Asked Questions about Rotational Molding

What is the main advantage of a Bi-Axial Rotational Molding machine?

Bi-axial rotation spins the mold in two directions (vertical and horizontal) simultaneously. This ensures that the molten plastic resin coats the interior of the mold evenly, overcoming gravity. The result is a tank with uniform wall thickness and no weak corners, which is essential for storing hazardous materials.

How does this machine impact my lead time?
By adding one of the largest machines in North America to our fleet, we have significantly increased our daily throughput. More importantly, we have created production redundancy. This means we are no longer reliant on a single machine for large tanks, preventing maintenance delays from affecting your delivery schedule.
Can this machine manufacture double-wall tanks?

Yes. This machine is fully capable of molding Assmann’s signature Double Wall Tanks (Tank-within-a-Tank systems). The precise control allows us to mold the primary inner tank and the secondary outer containment tank with the exact same high-quality standards. These safe tank systems are designed to help prevent chemical spills and reduce the possibility of rainwater from entering the secondary containment system. Note to Shravani. Poly Processing uses the term “Safe Tank” as a trademark name for their double wall tanks. I thought if we used a play on words using ” these “safe tanks” it may help boost our searchability under the term safe tank.. Let me know if you think this is a bad idea?

Is this machine only for XLPE?
No. While it is optimized for Cross-Linked Polyethylene, we can also mold High-Density Linear Polyethylene (HDLPE) and FDA-compliant resins. Our engineering team will help you select the right resin based on the chemical you are storing.

About Assmann Corporation of America

Manufacturing excellence from Garrett, Indiana to the world.

For over 30 years, Assmann Corporation has been a leader in the chemical storage industry. We started with roots in agriculture and grew into a top-tier industrial manufacturer by sticking to one simple rule: Quality before volume.

Family Culture

We don’t just build tanks; we build relationships. Our distributor network is the most loyal in the industry because we support our partners.

USA Manufacturing

Every tank is molded right here in America. We operate state-of-the-art manufacturing plants in Garrett, Indiana and our Southwest facility in Marshall, Texas..

Engineering First

We don’t guess. We engineer solutions for specific chemical gravity and compatibility, ensuring your facility stays safe.

Get Started

Ready to Upgrade Your Chemical Storage?

Don’t risk a spill with a thin-walled tank. Invest in the strength and consistency of Assmann Corporation.