Automated filament winding system increases throughput and reduces manual labor for pressure well reservoir production

Pressure well tank manufacturer Amtrol recently installed an automated filament winding line with in-process monitoring to produce its first line of composite lined tanks. In the photo, a KUKA robotic arm moves the polypropylene inner tub along the filament winding system. Photo credit: Amtrol

Amtrol (West Warwick, RI, USA) invented its first pre-pressurized well tanks in 1963. These tanks store water under pressure to reduce pump run time, decrease pump cycles and protect the whole of the system, Mike Giannantonio, general manager – cylinders and water systems at Worthington Industries (Columbus, Ohio, USA), says. Amtrol has run a successful business producing steel well reservoirs for nearly 60 years, but in recent years has invested in technology to develop a new line of composite reservoirs, using composites experience and financial resources of Worthington Industries, which acquired Amtrol in 2017.

Filament wound composite tank technology has been around for a few decades, but according to Alex Spires, senior project manager at Worthington Industries, this technology has evolved and been adopted in the well tank market over time. According to him, composite well tanks offer benefits to the market, including reduced condensation, increased durability and weight savings.

With Worthington Industries, Amtrol’s new composite tank link includes tanks of varying sizes, consisting of a polypropylene inner container and a thin fiberglass/epoxy outer wrap.

Over the past several years, Worthington Industries has worked with Roth Composite Machinery (Steffenberg, Germany) to develop a filament winding system to meet Amtrol’s need for an efficient and automated process to manufacture these relatively high volume tanks in different sizes. Built-in process monitoring capabilities were also important to ensure Amtrol’s market-recognized quality standards. Roth Composite Machinery was selected after years of supplying filament winding systems for the European facilities of Worthington Industries, which manufacture higher performance composite tanks for storing hydrogen and other high pressure substances.

automated composite filament winding line for Amtrol well reservoirs

This aerial illustration shows various stations on Amtrol’s filament winding line. Controlled by two human operators, the tanks are moved through the testing, winding and curing stations via three robotic arms and conveyors. Photo credit: Roth Composite Machinery

Automated filament winding line with in-process monitoring

The system, installed in late 2021, consists of a highly automated process located in a newly constructed, air-conditioned wing of the Amtrol facility.

For each tank, a polypropylene inner tank is first manufactured separately. Each tank that passes through the system is serialized with an RFID tag to record information such as the operator who built the tank, the temperature at which it was cured, the number of wraps, the epoxy mix ratio and leak test data. “He records all of this in a database that we maintain with our quality systems. If there should be a problem in the field, we can check this RFID tag and go back to production data to eliminate any problem. Additionally, the RFID tag enables inventory tracking for Amtrol and our customers,” says Spires.

automated filament winding line for composite well reservoirs

Each polypropylene container is fitted with an RFID tag, pressurized and flame treated before rolling. Photo credit: Amtrol

Each polypropylene tank is fed by an Amtrol operator onto a conveyor system, where it travels to the first station in the Roth line, the liner entry station. Here, a production shaft is inserted into each sleeve with a controlled torque setting. A robot places the liner on a carousel. The carousel can hold up to four liners; when filled to capacity, it rotates 90º, at which time the liners are pressurized and flame treated (see video below). The carousel then rotates another 90º, where the surface-treated liners are pressure-checked for leaks. If all passes, the carousel rotates another 90º and a robot moves the prepared containers from the carousel to an automatic filament winding system.

The filament winding cell consists of Roth’s “twin” winding machine (see video below), which offers winding on one side while the other side automatically loads and unloads containers via a robot. After winding is complete for each vessel, the fiber is automatically cut and attached to the finished vessel. Then the furling carriage is automatically moved to the other side of the furler and the furling continues on the next vessel. Depending on the size of the vat, winding times are around five minutes per vat, and the dual system allows near continuous winding during production.

Spiers notes, “Roth winding equipment allows glass overwrap winding patterns to be optimized to provide optimum protection and reduction in the overall amount of material on the tank.”

automated composite filament winding line for well reservoirs

Roth Composite Machinery’s dual coiling system coils two tanks at once (pictured right) while two more tanks await loading (left). Photo credit: Roth Composite Machinery

As each container is finished, it is transferred via a robot to a temperature-controlled conveyor that feeds it to the curing oven. The cured container exits the curing oven and is unloaded via a robot into a test station where the production shafts are removed, followed by final pressure and leak testing. If all tests pass, the finished part is automatically moved from the production cell via conveyors to Amtrol’s packing and shipping area.

Amtrol Titan Composite Well Tanks

Amtrol Titan is the first line of tank well tank composite products to be introduced by the company using the new automated production line. A second product line is expected to launch in late 2022. Photo credit: Amtrol

According to Joe Jansen, National Sales Manager for Roth Composite Machinery, the system only requires one to two people to operate, compared to the up to five to six people needed to operate many manual filament winding systems. He also says Roth’s automated cell is capable of producing more than three separate manual filament winding machines.

Jody McKinley, Director of Engineering at Amtrol, notes, “The quality and flexibility of Roth winding equipment is second to none and enables future growth opportunities for our company by adding new products and reducing the need for additional human capital due to automation. nature of the work cell.

Following the 2021 installation, Amtrol’s new line of Amtrol Titan tanks launched in the summer of 2022. A second brand of higher performance composite tanks called Amtrol Lift is expected to launch later this year.


Landscape photo credit: Roth Composite Machinery

Luz W. German