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February 24, 2020

1.1 Company introduction 1.2 Application range of Ever-power high quickness gearboxes Ever-power has been active in mechanical engineering for 25 years. For nearly 25 years, we’ve been production gears and mechanical gearboxes. Our purpose is to keep delivering state-of-the-art products to our customers through intensive core engineering and product development. We apply a maximally innovative planetary gearbox approach while addressing technical problems and specific requirements of our clients. Our goal is constant development of products with a higher degree of functional and quality parameters. We propose optimal solutions based on a thorough comprehension of every concrete software. We supply high-speed equipment units especially for thermal power station, heat plants, oil and gas sector or sugars refineries. High quickness gearboxes are a important component for applications this kind of: • Turbogenerator drives • Steam and gas turbine drives • Turbocompressor drives • Pump drives • Test benches Ever-power has tradition in high swiftness applications since 1977. The worldwide installation base of the parallel shaft gearboxes totals over 800 products. The calculation and design software KISSsoft and a 3D CAD program SOLID-EDGE along with other instruments allow us to be maximally fast and versatile. Our team of design engineers cooperates with universities, study institutes and leading experts from all over the globe. Ever-power uses state-of-the-art finite component method (FEM) software equipment for identifying and optimizing gear systems properties.
2.1 Product introduction High-velocity gearboxes designed and produced in Ever-power are designated mainly for power generation industry, compressor and pump applications. The manufacture is carried out on the present day machine equipment and gearboxes are assembled using own components or components given by European manufacturers. All products undergo thorough testing on a dynamic test bench. The design and gear strength calculation are performed according to API 613 5th Edition and AGMA 6011*. Product types: RS and RU gearbox type is designed to endure forces from meshing of double helical gears. They are not made to withstand any external axial or radial load. R1T and R2T gearbox type is designed to withstand forces from meshing of one helical gears and external axial and radial load. The transmission of exterior axial load from HS shaft to LS shaft is certainly by way of thrust collars. The gearbox is usually self supporting and doesn’t need any reinforcement. It includes a foot flange for mounting to a basis and jack bolts (levelling bolts) for easy set up. The gearbox does not require any unique maintenance. It is recommended to change the oil on regular basis or when changing the environment conditions – start to see the Operating Manual for details. Regular gearbox is adjusted for high speed procedure in the temperature range between -50 / +50°C provided the oil preheating at low temps and essential oil cooling at high temps. Should the gearbox be operated in hazardous region or under other unique conditions, it has to be contractually agreed. The typical gearbox efficiency is normally higher than 98,5%. Total efficiency depends upon plenty of factors, such as for example mesh losses, bearing losses, windage losses etc. Ever-power is competent to prepare personalized solution to raise the gearbox effi ciency up to 99,5%. mesh losses gearing is sized predicated on the transmitted power. Power is usually distributed by a customer. It is not possible to lessen mesh losses considerably, nevertheless Ever-power aims to optimize the losses to achieve the best compromise together with gear life, strength and NVH behaviour. bearing losses these losses possess the biggest impact on the gearbox performance. It is necessary to create and size the bearing correctly. windage losses windage losses possess big impact on the gearbox efficiency if the apparatus circumferential velocity is usually high. You’ll be able to decrease these losses (up to approx 50%) utilizing the windage cover. additional losses gearbox efficiency is also affected by the essential oil pump losses (if used), oil injection reduction etc.
2.3 Key specialized features Turbo Gear Units Catalogue © Ever-power Industry a.s. 2016, EN1604 Main Gearbox Components 2.3.1 Housing The housing includes 2 parts: the upper and the lower case. It really is fabricated steel building. The housing is certainly optimized by CAE methods to ensure once and for all stiffness, low sound emissions, superb cooling properties and minimum weight. In the low part there are feet for fixing the gearbox to the building blocks equipped by jack bolts and with provision for installation of earthing screw (if the gearbox is determined to the hazardous region). There is also located the oil insight/result fl ange and provision for temperature detectors conduction to the junction package. In the upper component there can be an inspection cover, looking at the correct lubrication of meshing gears, a breather and provision for vibration probes. Split face of the casing is usually horizontal, parallel to shaft axis. Both parts are connected by bolts and fi xed by dowel pins. 2.3.2 Shafts and gears Both shafts are forged items. HS shaft is definitely forged in one piece along with gearing. LS shaft and the gear are forged separately and the gear is warmth assembled on the shaft. The backsplash band is usually forged in one piece with the shaft or heat assembled. Both gears are floor to high precision. The teeth fl anks of HS pinion have special modifi cations to lessen the noise level and compensate the defl ection of shafts due to large load. A hunting tooth combination exists for mating gears when a tooth on the pinion does not repeat connection with a tooth on the apparatus wheel until it provides contacted all the other gear wheel tooth. The form of shafts ends depends upon customer’s request (cylindrical, tapered, fl anged etc.). Both shafts are dynamical balanced according to ISO 1940 or API 613. 2.3.3 Bearings Solely hydrodynamic bearings with an increase of sliding faces are used due to high speeds and bearing load. These bearings are split into bearings with: • fi xed geometry – there is absolutely no movement of sliding faces • tilting pads – sliding faces are moving
LS (low quickness) shaft is normally placed in simple journal bearings with cylindrical clearance (fi xed geometry). Among the bearings is certainly radial (on the non-driving end) and the additional one (on the generating end of the shaft) is combined radialaxial bearing. The look and calculation of the bearings are performed based on the latest methods. Bearings on HS (high speed) shaft are often tilting pad type because of high speed and pitchline velocity and both of these are radial bearings. Tilting pad bearings usually have four or five 5 pads and static load path goes either on one pad or between pads. Lubrication of the bearings can be reached by overflowing the area between pads or oil injection between pads by means of many nozzles which also protects pads against circumferential motion. When oil injection is used it is possible to decrease friction losses significantly. These bearings have the best resistance against rotor instability because they don’t generate any load leading to instability
2.5 Gearbox Testing 2 Item description and key features 3 Gearbox selection 1 Introduction 2 Product description and key features 2 Item explanation and key features 2.5.1 Load exams of high-acceleration gearboxes Testing laboratory for high-velocity gearboxes is a camera monitored modern workplace at Ever-power manufacturing plant in Pilsen. The Dynamic Check Bench is a testing facility equipped with a computer managed 1 MW electric motor with increase to 3.600 rpm, controlled load by a generator up to 710 kW of power, auxiliary gearboxes enabling testing of the main gearbox with speed up to 35.000 rpm. The check bench have a lubrication center with adjustable essential oil fl ow from 10 to 1 1.600 liters/ minute, controllable oil temperature and water cooling up to 800 kW of power. The lubrication is usually supported with pneumatic pumps supplying full volume of oil in the event of power outage. The tests process is automatically recorded while oil and bearing temperature, pressure, noise, total and relative vibrations are measured and used in a control space for evaluation by a specific software.