Coated Traction Products (Ctp®) — A Milestone In Elevator Rope Technology

The advantages of Brugg’s coated elevator ropes are detailed.

In 2010, Brugg Lifting’s Coated Traction Products (CTP®) earned Liftinstituut certification, and the years since have seen the polymer-coated wire rope installed in 100,000 elevators across Europe. In 2017, CTP received Japanese Transport Ministry approval, and the company’s goal is to have it approved for use in North America this year.

Brugg originally developed CTP in a partnership with a Spanish elevator manufacturer and later began working with a large global OEM. Today, CTP is used by 30 European elevator manufacturers. Its European standard approves it for 20:1 applications, but to meet ASME A17.7 for use in North America, it will be certified for 40:1 applications.

CTP works with direct overhead or machine-room- less (MRL) setups. It can use smaller drive sheaves, which means smaller machines can be used. Smaller machines mean less space taken up in the hoistway or machine room. However, round U-grooved sheaves must be used.

It is readily available in 6X19 construction, in diameters of 6.5 mm (23.6 kN minimum breaking load) and 8.1 mm (33.56 kN minimum breaking load). There is no limitation on lifting heights, but to date, CTP has been used in applications of 75 m or shorter. The 6.5 mm CTP can be used with sheave diameters as small as 115 mm, while the 8.1 mm CTP can use sheaves as small as 120 mm. Some of the advantages of CTP include:

• Sheaves up to 70% smaller than those used for conventional ropes
• As much as 20% less weight, compared to conventional ropes
• Greater life of rope and sheave
• Can reduce rope maintenance costs as much as 100% — no need for lubrication, which also means no thrown-off grease to clean up
• Reduces investment by 40%
• Coating eliminates or significantly absorbs vibration, making for a smoother ride.

CTP is thoroughly lab-tested. For example, a two-year- long “lifetime” test of the 8.1 mm rope completed in March involved a D:d 32:1 bending fatigue test of more than 93 million bends without a failure. With its significant installed base, CTP has also compiled a record of real-life data. Other laboratory procedures included fleet angle, traction and coating pull-out tests. As a result, CTP holds Liftinstituut lifetime certifications of 4.8 million bends for D:d > 20, and 2.4 million bends for D:d > 15. The company plans to certify it for 12 million bends in the North American market. If this certification is attained:

• Ropes on a 2:1 elevator will see four bends on the most-used rope section for every trip.
• 12 million trips divided by four bends per trip equals three million trips.
• If the average elevator sees 150,000 trips per year, that would give CTP a 20-year 2:1-roped elevator life. CTP is part of a range of Brugg products manufactured at facilities in Switzerland and China that are available worldwide, thanks to a global network of warehouses. The company is certified according to ISO 9001:2015 and ISO 14001:2015.