Featuring the Cat C13 engine, the 349D L boasts a net power rating of 283 kW (380 hp). The C13 integrates an innovative intake-air management system with an electronically controlled, mechanically actuated, unit-fuel injection system (MEUI) that yields steady power in all operating situations and exceptional fuel efficiency.
Hydraulics
The 349D L is designed with a powerful implement-hydraulic system that generates a maximum flow of 734 L/min (194 gpm) and operates at a relief pressure of 35 000 kPa (5080 psi). The hydraulic system automatically gives priority to boom-up and swing functions, eliminating the need for operator-selected work modes and increasing cycle times. Operation of the pilot-actuated main control valve is proportional to lever movement, assuring precise response and excellent controllability in all applications.
The design of the hydraulic system positions major components?main pumps, control valve and hydraulic tank?close together, allowing the use of shorter hydraulic lines for reduced frictional losses and minimal pressure variations. Regeneration valves in the digging arm and boom circuits transfer oil between cylinder ends, reducing unnecessary hydraulic flow by minimising the volume of oil exhausted to reservoir, the desired outcome of which is faster cycle times and greater fuel efficiency.
A choice of hydraulic circuits allows one-way, two-way or combined hydraulic flows to efficiently operate a range of heavy-duty hydro-mechanical work tools. This means the 349D L can be put to work in applications such as demolition, scrap processing and breaking road surfaces and bedrock.
Front linkage, structures, undercarriage
The 349D L offers a choice of front linkage options that allow the matching of machine capability to a wide range of applications. Boom construction features a large cross-section with internal baffle plates and the use of forged steel in critical high-load areas, such as the boom-foot and boom-cylinder connections. The stick is made of high tensile strength steel and features a large box section design that integrates interior baffle plates and a heavy bottom wear plate for durability.
The 349D L is available with a fixed gauge undercarriage. Track links are designed to reduce stress concentration and are sealed with grease to decrease internal bushing wear, reduce travel noise and extend service life. An idler guard and bolt-on centre guard help maintain track alignment when travelling or working on slopes. Three-stage planetary final drives assure positive power to the tracks, and a straight-line travel circuit keeps track speed consistent if the front linkage is operated.
The heavy-duty main frame is designed and fabricated for maximum durability, with box section main channels connected by a large diameter tube at the boom foot to add rigidity and strength. A durable car body supports the track-roller frames, which incorporates press-formed pentagonal structures that are exceptionally strong. Robotic welding achieves three times the penetration of a normal weld, providing extremely durable structures.
Operator safety, convenience and serviceability
The 349D L is equipped with certified ROPS cabs that comply with ISO standard 12117-2:2008. The new ROPS cab design features a larger, more comfortable environment intended to provide enhanced visibility, lower operator sound levels and improved serviceability.
Compared with the previous design, the glass area in the new cabs is increased 12 per cent, and the interior volume is larger by three per cent with improved pressurisation. The use of viscous rubber mounts dampens vibration to ensure optimal operator comfort.
The ROPS cab design allows the Falling Object Guard System (FOGS, ISO 10262) to be bolted directly to the cab to meet job site specifications. The cabs feature pilot-operated joysticks for all implement and swing functions, which provide smooth precise operation.
Pilot-operated control levers reduce operator effort, and a choice of joystick or foot pedals options modulate the operation of hydro-mechanical tools. For operator convenience and machine protection, the 349D L’s instrumentation, prior to start up, checks engine oil, hydraulic oil and engine coolant fluid levels, and then advises the operator in one of 27 different languages.
To lower operating costs, the 349D L features extended fluid service intervals, centrally located service points to facilitate ground level maintenance and a readily accessible greasing block on the boom for lubricating hard to reach locations. S O SSM fluid sampling ports for the engine and hydraulic system enables faster, more effective samples to be taken ? thereby ensuring long life and reliability. A pilot-system filter, in-tank hydraulic oil cartridge filters, radial-seal air cleaner and a fuel/water separator integral with the primary fuel filter assist in keeping the 349D L running reliably to protect the customer’s investment.
The 349D L also is equipped with the Cat PL321 Product Link system that uses Cat Asset Watch software to provide time-based fencing (determining when the machine can operate) and reporting of machine hours and location. There is the additional option of adding Health Watch and Maintenance Watch software that expands system capability to include codes from on-board sensors, fuel data and maintenance-related reporting.
Basic Specifications
Engine make/model
Cat/C13
Net power (kW/hp)
283/380
Operating weight (kg)*
44,800 to 51,100
Hydraulic flow (L/min/gpm)
734/194
Relief pressure (implement) (kPa/psi)
35,000/5080
Maximum digging depth (mm)**
7650
Maximum digging depth (mm)***
6700
*Depending on machine configurations
** With 6.9m reach boom and 3.4m stick
*** With 6.5m mass boom and 2.5m stick
Source: Caterpillar