Novibra Introduces LENA – the Low-Energy and Noise-Absorbing Spindle That Delivers the Highest Speeds

The Challenge

The overall high reliability and long service life of the spindles are decisive factors for spinning mills. Modern spindles are expected to deliver faster speeds and therefore increased productivity, no running-in time and less maintenance due to long lubrication cycles. The most important long-term goals are energy savings and the reduction of energy costs.

The Solution

Novibra confirms its market leadership and leverages its proven spindle technology to deliver on this common need with the LENA spindle, which offers Low Energy and Noise Absorption.

LENA is the latest addition to Novibra’s spindle family and combines the well-known, successful spindle technology and design concepts of Novibra with new features. Novibra’s spindle technology is characterized by a unique hydro dynamic two-level bearing system that effectively absorbs imbalances caused by belt tension, full cop imbalances and traveller tension. The absorption of imbalances leads to the industry’s longest operational lifetime and high reliability.

LENA was designed to achieve the highest speeds with low energy consumption, achieving speeds of up to 30 000 rpm while saving on average up to 4 to 6% of energy.

For efficient noise reduction, LENA features a second damping system. This unique and well proven Noise Absorbing System Assembly, known from Novibra NASA spindles, ensures minimum neck bearing load as well as minimum vibration and low noise level at high speeds. 
The LENA neck bearing diameter was reduced to 5.8 mm and thanks to the smaller bearing, the wharve diameter could also be reduced to only 17.5 mm. From a power transmission perspective, reducing the wharve diameter allows the machine to be operated at a lower speed – compared to spindles with standard wharve diameter – while keeping the same speed of the spindle itself and thus the desired yarn count and twist. The small wharve diameter of the LENA spindles is unique in the market.

The footstep bearing unit consists of a radial and an axial bearing. The radial bearing is designed as a hydrodynamic plain bearing with the internal diameter of 3 mm. It’s the small diameter of the shaft’s tip that allows additional energy saving as the power consumption of the radial bearing is directly influenced by its own diameter, on top of many other factors. This correlation has been confirmed already by a low energy consumption of the HPS 68/3 spindles. All these optimizations make the energy savings possible.

Customers Confirm Energy Savings in Independent Tests

The main target application for LENA spindles is spinning with tube lengths up to 210 mm at high speeds up to 30 000 rpm. All material can be spun with LENA and the spindle is suitable for yarn counts of Ne 30 and finer. Many Novibra customers trust LENA spindles for their daily production. Some of them reported their results of their own energy saving tests.

A customer in India conducted an independent power study after installing LENA spindles with clamping crown CROCOdoff on a LR60/AX ring spinning machine. Polyester and cotton were spun, with a yarn count Ne 30 and a spindle speed of max. 20 000 rpm. The customer profited from a power saving effect of 6.5% thanks to LENA as well as a reduction of yarn breakage during the start-up of the machine. An additional observation was that the incidence of low twist yarn was eliminated after installation of the Novibra spindles.

Another valued customer in India compared the overall energy consumption using LENA spindles and reported a saving effect of 4.6% per machine after the installation of LENA spindles on a LR6/S ring spinning machine with manual doffing. Their trial was performed with cotton, yarn count Ne 60 and the spindle speed went up to a maximum of 22 700 rpm.

Installations and Options

The installation of LENA requires only a small change in the machine settings, making the spindle commissioning fast and easy. LENA spindles can be equipped with state-of-the-art cutting and clamping crowns (e.g. CROCOdoff). CROCOdoff enables underwinding-free doffing which significantly reduces its maintenance and optimizes the automation of spindle operation. Crocodile-like teeth ensure dependable clamping and cutting of the yarn while doffing and reduce the number of after-doff ends down.

This shows that LENA spindles significantly contribute to energy savings during ring spinning and a lower noise level in spinning mills – even at the highest spindle speeds – thanks to various technological optimizations.

Novibra is the only manufacturer in the world that offers spindles with a wharve diameter as small as 17.5 mm. Unmatched expertise and in-depth experience allow Novibra to launch innovative products such as LENA, delivering significant improvements over conventional spindles and keeping our customers at the forefront of their industry.