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How we engineer reliability

– The innovations and technologies that keep Torverk's industrial doors running for 40 years.

Downtime is one of the most expensive things that can happen to a business.

Your staff stand idle while wages keep ticking, and deliveries freeze. Recurring problems quickly send customers to your competitor.

Researchers at Chalmers University of Technology have calculated that production disruptions cost Swedish companies more than €10 billion a year. In many businesses, the losses are as large as the profit margin.

Most downtime is caused by power cuts, machine breakdowns or human error. But sometimes all it takes is a door that won't open.

That is why the cheapest door is the one that never stops.

At Torverk we engineer our doors so they never become the weak link. Every component is dimensioned for a reality where doors get hit by vehicles, temperatures swing, and openings are counted in the hundreds of thousands.

Here are the technical solutions behind our construction.

Torverk’s in-house motor drive, the industrial door motor tested through 2.6 million opening cycles

A drive built for hard work

A drive system dimensioned for 2.6 million opening cycles

The drive is the moving part that goes through the most cycles. Day after day, resistance and friction slowly grind a door motor down.

Back in the 1960s we developed a motor drive with every gear and shaft oversized to withstand sustained loads. There is nothing in the construction that is built to fail. Built-in load monitors sense when the counterforces grow too large and stop the door before anything breaks.

When we tested it, we switched the test door off after 2.6 million openings. That is enough to open the door 100 times every working day for 100 years.

When the drive lasts, the door lasts.

TrueFrame™, Torverk’s torsionally rigid cassette construction for industrial door leaves

A torsionally rigid sandwich construction

A shape-stable construction that lasts

In industrial environments, a door has to take the occasional knock from a forklift or a vehicle. But a door that is built too lightly loses its shape and starts to bind. That puts more load on the motor and wears the hinges. Over time, small deformations turn into big problems.

Our cassette construction combines a sheet metal frame, reinforcements and a sandwich structure that work together to give high torsional rigidity and shape stability. The construction is developed to hold its geometry, even when real life is less than gentle.

Shape stability is the foundation of reliability.

Lifting hinges that reduce friction and wear

When the energy crisis hit in the 1970s, heating industrial buildings became expensive. To improve insulation, we fitted seals all the way around our door and between every section. But the floor seals dragged along the ground and wore out in no time.

So we invented a lifting hinge that raises the door one centimetre before it opens. That eliminates friction against the floor and spares the seals.

Less friction means less wear, and a longer working life.

At the same time, the door is pressed down slightly as it closes and seals more tightly along the bottom edge, which improves energy performance.

High-density polyurethane foam in a Torverk industrial door leaf, insulating four times better than standard building insulation

An insulating core that also provides structural strength

We used to weld a frame of square tubing and fill it with mineral wool. The construction was strong, but the insulation performance fell short. The door leaked heat, sometimes to the tune of thousands of euros a year.

The challenge is that an industrial door is always thinner than an exterior wall, yet is expected to insulate almost as well.

Today we use a sandwich construction instead, injecting high-density polyurethane foam into the cassette. The foam expands and fills every cavity. As it cures, it bonds the components of the door leaf into a single, rigid structure.

The result is a door that insulates effectively and holds its shape over time.

Industrial door seals made from EPDM rubber and EP rubber with a low plastic content

Our safety edge (the upper seal on the left) has two copper wires embedded in electrically conductive rubber. If anything is in the door’s path, an electrical circuit closes and the door stops.

EPDM seals for long-lasting elasticity

Ordinary rubber is broken down over time by UV light, ozone and temperature swings. It hardens, cracks and loses its elasticity.

Our seals are made from EPDM rubber and EP rubber with a low plastic content. That gives a more stable chemical structure. The seal does not shrink, keeps its elasticity for years and goes on sealing effectively, even in harsh climates.

A seal that doesn't crack is a seal that keeps working.