Bulldozer-loosening unit DET-400 in Moscow

Details Category: Bulldozers and tractors Published: 08/04/2016
DET-400 is a bulldozer that has been produced by the Chelyabinsk Tractor Plant since 2007. This model is a product of modernization of the earlier model DET-320. The vehicle belongs to traction class 25 and has an electromechanical transmission.

1. general description
2. Main nodes
3. Cabin
4. Specifications
5. Advantages
6. Modernization

The abbreviation DET should be understood as Diesel Electric Tractor. This model boasts that it was the first in the world to combine an electromechanical type transmission with switched reluctance electric machines, as well as an electrical control system. The bulldozer is used in soil excavation, transportation or loosening work. Work is carried out on soils of four categories, as well as on frozen or rocky rocks.

Features of the DET-400 tractor

The electromechanical transmission of previous models of similar equipment - DET-250M2 and DET-320 - was not so progressive. The use of switched reluctance electric machines provides the following features of DET-400:

• The rotors of induction motors do not have a winding, and motor failure for reasons related to the rotor is excluded. If the starter coil is damaged, it can be replaced without dismantling adjacent coils. This cannot be done on other types of electric motors.
• Working in high humidity conditions is not a problem.
• The weight and dimensions have been reduced by 10-15 percent compared to engines of previous designs; copper consumption was reduced by 0.5 tons.
• The transmission power generator can be used as a diesel generator set.
• The control system is non-contact, highly reliable; equipped with an on-board computer and a graphic display in the tractor cabin. It guarantees automatic adjustment of the operation of electric machines; informs the operator about the current operating modes of the electromechanical transmission.

Tests have demonstrated the provision of the most optimal traction characteristics throughout the entire traction range of the DET-400 tractor: the control system constantly maintains engine loading at nominal mode. In general, the reliability of this design is no less than twice as high as the previous one.
Bulldozer-ripper units based on the DET-400 industrial tractor have been produced at ChTZ since 2007. In 2012, a modernized version, DET-400M, was put into production. This machine has received an updated design with a plastic lining. Cummins diesel engines began to be installed on the DET-400M tractor; drive and idler wheels, tracks and rollers from Caterpillar. A new hydraulic system was also introduced, and it became possible to control the tractor’s hydraulics using a joystick.

The modernized version of the “four hundredth” can be used not only as a bulldozer, ripper and traction winch, as stated on the official website of ChTZ-UralTrak OJSC, but also as a “power plant on tracks”: a welding machine and other electrical appliances can also be connected to it. DET-400M will be able to “energize” an electric locomotive and even a small village.

Tractor engines DET-400

DET-400 tractors are equipped with two types of turbocharged diesel engines: YaMZ-7513.10, or Cummins QSM-11. Turbocharging is gas turbine, with one turbocharger and with intermediate cooling of the charge air.

Characteristics and parameters of the YaMZ-7513.10 diesel engine (eight-cylinder):

• Working volume – 14.86 l.
• Operating power – 272 kW, or 370 hp.
• The nominal rotation speed is 1900 rpm.
• Cylinder diameter – 130 mm, piston stroke – 140 mm.
• Weight – 1250 kg.

Characteristics and parameters of the Cummins QSM-11 diesel engine (six-cylinder):

• Working volume – 10.8 l.
• Operating power – 274 kW, or 375 hp. Operating power – 272 kW, or 370 hp.
• The nominal rotation speed is 1900 rpm.
• Maximum torque – 1780 N.m, at 1800 rpm.
• Weight – 984 kg.

Similar Cummins engines are used on some industrial tractors Hyundai, New Holland, Terex, Chetra; on some models of heavy BelAZ dump trucks.

The lubrication system for YaMZ and Cummins engines is combined: under pressure and splashing, with two oil filters. The diesel fuel supply system is of a separate type, with two coarse filters with a “Separ-2000” water separator, and a fine diesel fuel filter with a replaceable filter element. The cooling system is liquid, closed type, with a front-mounted radiator and a fan. Starting system – main: traction generator IG-250; additional: engine starter.

An additional option is to equip the tractor with a PZD-30E engine pre-heater.

Electromechanical transmission of the DET-400 tractor

The DET-400 tractors are equipped with an electromechanical transmission with switched-reluctance alternating current electric machines (VID) - two-speed, with automatic changes in traction forces and machine speeds, depending on changes in traction resistance. Since the transmission operates in automatic mode, the operator is freed from the need to change gears during excavation and transport work.

DET-400 (2007-2012).

The maximum traction force is no less than 443 kN. The speed of the bulldozer ranges from 0 to 14.3 km/h - the same in both forward and reverse gears. The electric transmission control consists of a BS-400 power unit with a rated power of 240 kW. The supply voltage for starting is 24+5V. The battery charging power is 3.5 kW. The number of batteries is four. Cooling – forced, air.

Transmission electrical equipment

The electrical equipment of the Chelyabinsk bulldozer also includes: ID-240 traction motor, IG-250 induction generator, BOSDT-250 temperature sensor signal processing unit, BM-400 microcontroller unit (on-board computer). The rated power of the ID-240 electric motor is 235 kW; rated voltage – 600 Volts; rated current – ​​560 Ampere; rotation speed – 430…2650 rpm. The mass of the traction motor is 2.53 tons.

DET-400M (since 2012)

The induction generator has a rated power of 250 kW. The rated voltage is 600 Volts; rated current – ​​600 Ampere; rotation speed – 2350…2650 rpm. The mass of the induction generator is 1.175 tons. The BOSDT-250 temperature sensor signal processing unit operates at a rated voltage of 24+5 Volts; It is air-cooled and weighs 2.46 kg. The BM-400 microcontroller unit also operates at a nominal voltage of 24+5 Volts; equipped with air cooling; its weight is 10 kg.

Mechanical part of the transmission

As part of the mechanical part of the transmission of the DET-400 tractor, there is a safety clutch - friction, multi-disc type, dry friction. The drive of the IG-250 generator consists of a step-up gearbox with a pair of cylindrical helical gears.

Receiving two gears (forward and reverse), as well as turning and braking the bulldozer are provided by planetary turning mechanisms (PSM). These mechanisms have a planetary gear set, which consists of a system of gears in constant mesh; locking clutch and 2 brakes. The planetary rotation mechanisms are controlled by one lever, through a hydraulic servo drive.

The final drive is two-stage, with a pair of spur gears and a planetary gear. Transfer gearbox with power take-off shaft - a pair of spur gears to drive hydraulic system pumps and a pair of bevel gears to drive the transmission oil pump. The turn is carried out in a standard way for heavy tracked vehicles: by reducing the speed of one track relative to the other.

Control

Two two-stage planetary turning mechanisms (PMP) provide two gears (I-working, II-transport) forward and backward, turning and braking the tractor. The PMP is controlled by one lever through a hydraulic servo drive.

Construction of the DET-400 chassis

The tractor bogies are welded, made from rectangular channels. The suspension is torsion bar, individual for each road wheel, closed to the bogie frames. The tension wheels are made of solid cast, closed type. Track rollers as part of the chassis - 12 units; support rollers – 4 units. The width of the track shoe is 66 cm, the number of these shoes is 56 pieces.

The design uses closed-type solid-cast tension wheels. The track tensioning mechanism is hydraulic. Each track belt has 56 links; the pitch is 218 mm. The lug height is 70 mm. The installation of additional lug spurs is offered as additional equipment. In general, the DET-400 chassis provides smoother movement compared to DET-320 and DET-250 and is highly reliable.

Weight and Dimensions

Designation

Some technical characteristics and parameters in numbers

• The operating weight of the tractor is 36.454 tons.
• The operational weight of the bulldozer is 42,270 tons.
• The operating weight of the bulldozer with ripper is 46,550 tons.
• The operating weight of the bulldozer with a traction winch is 48,180 tons.
• Length – 6750/7370/8720 mm (without equipment/with blade/with blade and ripper);
• Width – 3110/4250/4250 mm (without equipment/with blade/with blade and ripper);
• Height – 3900/3900/3900 mm (without equipment/with blade/with blade and ripper);
• Track width – 2.45 m.
• Base – 3.2 m.
• Fuel tank capacity – 600 liters; hydraulic system - 165 liters; cooling systems - 76 liters; lubrication systems - 30 liters; lubrication and transmission control systems - 80 liters.

Refill tanks

Bulldozer and loosening equipment DET-400

Bulldozer-ripper units based on the DET-400 tractor are equipped with a hemispherical blade of the B-1 type, with fully hydraulic control for changing the cutting angle and skew. The volume of the drawing prism is 10.5 cubic meters; The width of the blade is 4.25 m, its height is 1.85 m. The blade rises to a maximum height of 1.225 m. The greatest depth of the blade is 0.5 m. The main cutting angle is 55 degrees. The lateral tilt angle of the blade is 10 degrees.

The mass of bulldozer equipment is 5.09 tons. The DET-400 tractor can also be equipped with a coal blade (type “K”) with a drawing prism volume of 19.5 cubic meters and a blade with narrow railway dimensions (type “B2”).

The ripper equipment is a 4-link with a single-tooth ripper and an adjustable cutting angle (type “P2”). The greatest depth that this equipment guarantees is 1.515 m. The loosening angle varies in the range of 40...65 degrees. The weight of loosening equipment for DET-400 is 3.5 tons.

Hydraulic system

Tractor cabin DET-400

The cabin on the DET-400 meets modern standards of safety and comfort for the operator’s workplace. It is made with large panoramic glazing. The cabin glass is double-glazed, which significantly increases the thermal and noise insulation of the workplace. In the cabin of the DET-400 tractor, a powerful Zenit heater and Rio-3000 air conditioner are installed as standard.

There are two seats in the cabin. The operator's chair is equipped with a set of adjustments for backrest tilt and height. Instruments and controls of heavy machinery are located in accordance with current ideas about workplace ergonomics.

It is easy to control the main processes without interrupting your main work. The instrument panel is equipped with a graphic display and an on-board computer, which automatically controls the equipment.

Reviews from DET-400 bulldozer operators

There are very few reliable reviews on the Internet from people who have had the opportunity to work on DET-400 bulldozers for any significant time. Therefore, it is not possible to obtain an accurate picture about a given machine without the subjective perception of one or another operator.

These few reviews note that compared to its predecessors - DET-250 and DET-320, DET-400 is a step forward. This bulldozer is “nimble,” confirms another operator. New engines do not consume oil as much as older ones. “Finally, the tracks were redone and the combs, which kept breaking, were removed.”

However, the chassis of the DET-400 bulldozer is called weak, “the tractor has become heavier, and the brakes are old, the brake bands do not last long.” According to one of the machine operators, who after several years of working with DET-400 switched to Chetra, bulldozers of this brand are more durable and reliable than DET.