1.1 Company introduction 1.2 Application range of Ever-power high swiftness planetary gearbox gearboxes Ever-power has been energetic in mechanical engineering for 25 years. For almost 25 years, we’ve been production gears and mechanical gearboxes. Our goal is to keep providing state-of-the-art products to your customers through intensive core engineering and product advancement. We apply a maximally creative approach while addressing specialized problems and specific requirements of our clients. Our goal is continuous development of products with a higher degree of practical and quality parameters. We propose optimal solutions based on an intensive comprehension of every concrete program. We supply high-speed equipment units particularly for thermal power station, heat plants, oil and gas sector or glucose refineries. High quickness gearboxes are a important component for applications such: • Turbogenerator drives • Steam and gas turbine drives • Turbocompressor drives • Pump drives • Test benches Ever-power has custom in high speed applications since 1977. The worldwide installation base of the parallel shaft gearboxes totals over 800 systems. The calculation and design software program KISSsoft and a 3D CAD program SOLID-EDGE along with other instruments allow us to be maximally fast and versatile. Our team of style engineers cooperates with universities, analysis institutes and leading specialists from all over the world. Ever-power uses state-of-the-artwork finite element method (FEM) software tools for determining and optimizing gear devices properties.
2.1 Item introduction High-speed gearboxes designed and manufactured in Ever-power are designated primarily 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 supplied by European producers. All products undergo thorough testing on a dynamic test bench. The look and gear strength calculation are performed according to API 613 5th Edition and AGMA 6011*. Item types: RS and RU gearbox type is made to endure forces from meshing of double helical gears. They aren’t made to withstand any exterior axial or radial load. R1T and R2T gearbox type is designed to endure 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 through thrust collars. The gearbox is usually self supporting and doesn’t need any reinforcement. It has a foot flange for mounting to a foundation and jack bolts (levelling bolts) for easy set up. The gearbox does not require any special maintenance. It is suggested to change the oil on regular basis or when changing the climate conditions – see the Working Manual for details. Regular gearbox is altered for high speed operation in the temperature range between -50 / +50°C provided the oil preheating at low temperature ranges and oil cooling at high temps. Should the gearbox be managed in hazardous area or under other special conditions, it has to be contractually agreed. The typical gearbox efficiency is normally higher than 98,5%. Total efficiency depends on plenty of elements, such as mesh losses, bearing losses, windage losses etc. Ever-power is capable to prepare personalized solution to boost the gearbox effi ciency up to 99,5%. mesh losses gearing can be sized based on the transmitted power. Power is given by a customer. It isn’t possible to lessen mesh losses considerably, however Ever-power aims to improve the losses to achieve the best compromise as well as gear life, sturdiness and NVH behaviour. bearing losses these losses have the biggest impact on the gearbox performance. It is necessary to create and size the bearing properly. windage losses windage losses have big influence on the gearbox efficiency if the gear circumferential velocity is high. You’ll be able to reduce these losses (up to approx 50%) utilizing the windage cover. other losses gearbox efficiency can be affected by the oil pump losses (if used), oil injection loss etc.
2.3 Key technical 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 usually optimized by CAE methods to ensure once and for all stiffness, low noise emissions, excellent cooling properties and minimum weight. In the low part there are feet for fixing the gearbox to the foundation outfitted by jack bolts and with provision for mounting of earthing screw (if the gearbox is set to the hazardous region). There is also located the oil insight/output fl ange and provision for temperature detectors conduction to the junction container. In the upper part there can be an inspection cover, checking the proper lubrication of meshing gears, a breather and provision for vibration probes. Split face of the casing is definitely 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 parts. HS shaft is usually forged in one piece along with gearing. LS shaft and the apparatus are forged separately and the apparatus is heat assembled on the shaft. The backsplash ring is usually forged from one piece with the shaft or high temperature assembled. Both gears are surface to high precision. Teeth fl anks of HS pinion have special modifi cations to reduce the sound level and compensate the defl ection of shafts because of weighty load. A hunting tooth mixture exists for mating gears whenever a tooth on the pinion will not repeat contact with a tooth on the apparatus wheel until it offers contacted the rest of the gear wheel tooth. The shape of shafts ends depends on customer’s ask for (cylindrical, tapered, fl anged etc.). Both shafts are dynamical balanced in accordance to ISO 1940 or API 613. 2.3.3 Bearings Solely hydrodynamic bearings with more sliding faces are used due to high speeds and bearing load. These bearings are divided into bearings with: • fi xed geometry – there is absolutely no motion of sliding faces • tilting pads – sliding faces are moving
LS (low rate) shaft is normally placed in plain journal bearings with cylindrical clearance (fi xed geometry). One of the bearings can be radial (on the non-traveling end) and the additional one (on the generating end of the shaft) is combined radialaxial bearing. The design and calculation of the bearings are performed based on the latest strategies. Bearings on HS (high speed) shaft are usually tilting pad type because of high rate and pitchline velocity and both of them are radial bearings. Tilting pad bearings will often have 4 or 5 5 pads and static load direction goes either using one pad or between pads. Lubrication of these bearings could be reached by overflowing the space between pads or oil injection between pads through a number of nozzles which also shields pads against circumferential movement. When essential oil injection is used you’ll be able to reduce friction losses substantially. These bearings have the best level of resistance against rotor instability because they do not generate any load causing instability
2.5 Gearbox Testing 2 Item description and key features 3 Gearbox selection 1 Introduction 2 Item description and key features 2 Item description and key features 2.5.1 Load lab tests of high-speed gearboxes Testing laboratory for high-acceleration gearboxes is a camera monitored modern workplace at Ever-power manufacturing plant in Pilsen. The Dynamic Check Bench is a examining facility built with a computer managed 1 MW electric motor with speed up to 3.600 rpm, managed load by a generator up to 710 kW of power, auxiliary gearboxes allowing testing of the main gearbox with increase to 35.000 rpm. The test bench possess a lubrication center with adjustable essential oil fl ow from 10 to at least one 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 assessment process is automatically recorded while essential oil and bearing temperature, pressure, noise, total and relative vibrations are measured and transferred to a control room for evaluation by a specific software.