【正文】 aders are not classified as earthmoving machinery, as their primary purpose is other than earthmoving. Unlike most bulldozers, most loaders are wheeled and not tracked, although track loaders are mon. They are successful where sharp edged materials in construction debris would damage 2 rubber wheels, or where the ground is soft and muddy. Wheels provide better mobility and speed and do not damage paved roads as much as tracks, but provide less traction. Unlike standard tractors fitted with a front bucket, many large loaders do not use automotive steering mechanisms. Instead, they steer by a hydraulically actuated pivot point set exactly between the front and rear axles. This is referred to as articulated steering and allows the front axle to be solid, allowing it to carry greater weight. Articulated steering provides better maneuverability for a given wheelbase. Since the front wheels and attachment rotate on the same axis, the operator is able to steer his load in an arc after positioning the machine, which can be useful. The loader assembly may be a removable attachment or permanently mounted. Often the bucket can be replaced with other devices or toolsfor example, many can mount forks to lift heavy pallets or shipping containers, and a hydraulicallyopening clamshell bucket allows a loader to act as a light dozer or scraper. In construction areas loaders are also used to transport building materials such as bricks, pipe, metal bars, and digging tools over short are also used for snow removal, using their bucket or a snowbasket, but usually using a snowplow attachment. They clear snow from streets, highways and parking lots. They sometimes load snow into dump trucks for transport. Front loaders gained popularity during the last two decades, especially in urban engineering projects and small earthmoving works. Many engineering vehicle manufacturers offer a wide range of loaders, the most notable are those of John Deere, Caterpillar, Case, Volvo, Komatsu and Liebherr.The following we will introduce Carter 938G Series II Wheel Loader.EngineThe 938G II provides more power, excellent fuel economy, and reduced maintenance.Turbocharged, ATAAC. Turbocharging packs dense air into the cylinders for more plete bustion and lower emissions. Airtoair aftercooling (ATAAC) provides a separate cooling system for intake manifold air. The ATAAC system reduces smoke and emissions by providingcooler inlet air for more efficient bustion.Constant Net Horsepower. The 938G II’s electronic engine is integrated with an ondemand cooling fan. The engine pensates for varying fan loads and provides constant net horsepower, regardless of operating conditions. A consistent level of “working” horsepower is provided and fuel consumption is reduced.Oil Change Intervals. The engine oil change interval is increased to500 hours (with CH4 oil), reducing costs and downtimePowerful Performance. The 3126B ATAAC engine delivers net power of 119 kW (160 hp), and meets EPA Tier 2 emissions standards. Its advanced system keeps fuel at low pressure in the fuel lines until it is injected into the cylinder. Fuel pressure is created hydraulically in response to a signal from the ADEM III? Electronic Control Module.Electronic Control Module. The Advanced Diesel Engine Module (ADEM III) fuel system is a proprietary electronic control module, which provides improved engine response and fuel efficiency,plus advanced diagnostics and reduced emissions. Altitude capability is increased to 3050 meters (10,000 feet) without derating. ADEM III allows full electronic integration of the engine and transmission for maximum power train efficiency.Power TrainAdvanced Caterpillar power train is reliable and fuel Power Shift electronic power shift transmission with automatic shift capability is a countershaft design built by Caterpillar. It is electronically controlled and allows full power shifts and directional changes. Fully modulated gear shifts contribute to operator fort and increase ponent Clutch Pressure Control (ECPC). Senses input from both the transmission and the operator controls in the cab to modulate each individual clutch through a proportional electrohydraulic valve. This results in smoother gear changes and improved shift quality. Energy is modulated into the clutches, resulting in longer clutch life.Integrated Braking System. New for G Series II, IBS integrates downshifting and transmission neutralization into the lefthand brake pedal. IBS provides smooth, optimized transmission neutralizer performance with a greater range of adjustability. The Integrated Braking System also lowers owning and operating costs by reducing axle oil temperatures, which can extend service brake Service. Daily transmission oil level check is done from the ground through a wellprotected sight oil sampling valve allows quick,clean access to the transmission for S?O?SSM oil analysis.Cooling SystemNew G Series II cooling package reduces radiator plugging and improves fuel efficiency.Reverse Flow. Air enters through the rear grill and exits out the top opening and side hood doors. Rear air flow picks up less debris from the ground, reducing plugging.Improved System Access. The 938G II adds a swingout grill, hydraulic oil cooler and air conditioner condenser for easier cleaning. Side panels open to allow access to both sides of all cores for cleaning. A heavy duty Airborne Debris Grill, with 4 mm perforations is available as an attachment.OnDemand Fan. Electronically controlled, variable speed ondemand fan adjusts to meet the varying cooling requirements of the machine. Fan speed is determined by oil, coolant and inletmanifold temperatures. In cooler operating conditions, average fan speed is reduced, resulting in less fuel consumption, lower noise levels and less radiator plugging.Unit Core Radiator. New unit core radiator with square wave shaped fin density (6 fins p