ⓘ Tatra 813

                                     

ⓘ Tatra 813

The Tatra T813 was a truck produced in Czechoslovakia by the Tatra company. It was produced from 1967 to 1982. The basic representative of this series was a military version of the 8×8 Kolos, which was able to pull trailers up to a total weight of 100 tons. Tatra also produced a civilian version in either 6×6 or 4×4. After fifteen years of production, 11.751 vehicles were built in all modifications. Many units were exported to the USSR, East Germany, Romania and India.

                                     

1. History

The first prototype which was made of Tatra 138 parts was built in 1960. It had permanent 4 × 4 all-wheel-drive. After the initial trials however the designers decided to develop and expand the concept to an 8x8 all-wheel-drive all-terrain vehicle. The basis of the design thus became the modular chassis of the Tatra 813. In 1983, it was succeeded by the Tatra T815.

                                     

2. Design and technology

A tubular backbone construction was chosen for the T813. The main advantages of the central load carrying backbone tube are the high torsional and bending stiffness protecting the trucks body from forces caused by the payload. Further advantages are that it houses all important parts of the drivetrain and that it allows a concept of modular construction where designers and customers can choose between two, three and four axle versions and various wheelbase combinations. A new cab-over-engine design was implemented, as were the wide profile super single tyres and central tyre inflation/deflation system.

                                     

2.1. Design and technology Engine

The naturally aspirated V12 engine T-930 was created by adding four additional cylinders to the existing T-928 75° V8 engine, used in the Tatra T138. The crankshaft consisted of six individual journals bolted together with front and rear pins all running on the main roller bearings and located on the axial friction thrust washers. The military version was multi-fuel capable, running on any mixtures of diesel fuel, petrol and kerosene aviation fuel.

                                     

2.2. Design and technology Chassis

The chassis is a full-length backbone tube with independent swing half axles available as either 4×4, 6×6 or 8×8 model. 4×4 models had a front axle suspension system with adjustable torsion bars, in the 6×6 and 8×8 models front and rear axles had longitudinal semi-elliptic leaf springs. For the 4×4 configuration the rear axle had air suspension. Permanent all-wheel-drive, front twin steer 6×6, 8×8 drive via homo-kinetic drive shafts, lockable differentials, inter-axle differentials with locks and planetary hub reductions were standard for all models. Unlike many six-wheeled vehicles, which have a single front axle and tandem rear axles, 6×6 versions used twin steering front axles- as with the 8×8- and a single rear axle.

  • 2030 mm NT, NTH Prime movers
  • 1990 mm 6×6 Hauler, S1, 8×8 Chassis
  • 2050 mm KOLOS
  • Front track
  • Rear track
  • 1950 mm
  • 2000 mm 8×8 KOLOS
  • 1990 mm NT, NTH Prime movers
  • S1 8×8 - 1650+2800+1450 mm
  • 8×8 Chassis - 1650+3200+1450 mm
  • Wheelbase
  • 6×6 Hauler - 1650+2700 mm
  • T813 KOLOS - 1650+2200+1450 mm
  • NT, NTH 4×4 - 3700 mm
  • 330 mm 8×8 Chassis, S1 8×8
  • 300 mm NT, NTH Prime Movers
  • Ground clearance
  • 380 mm KOLOS, 6×6 Hauler


                                     

2.3. Design and technology Transmission

The main gearbox was located behind the cabin and connected to the engine clutch housing via a short cardan shaft this design enables a so-called flat floor cabin. The main gearbox was bolted to an auxiliary gearbox, to a transfer case and then to a backbone tube and formed the main part of the chassis structure. A rear power take off and a winch drive were available as a factory option. Main and auxiliary gears were fully synchronized except the first and reverse gear. The new feature was a unique 2-speed planetary overdrive system bolted between the front and rear axles. The overdrive could only be selected manually while the vehicle was not moving. The auxiliary gearbox had a neutral position which allowed the winch and a power take off to use the main gearbox gearing for variable speed operation. From the backbone tube the torque was transmitted to the wheels via Tatra gear differentials with differential locks, offset drive shafts and planetary hub reductions.

  • gear ratios - 19.97, 24.96, 32.83, 41.68, 51.0, R8.58
  • Main gearbox - 5+1 2-5 gear synchronized KOLOS 8×8 & Hauler 6×6
  • splitter ratios - 1.0 Direct, 0.75 Overdrive electro-pneumatic control via switch on the gear lever and clutch pedal activated
  • Main gearbox - 5+1 2-5 gear synchronized with splitter direct and overdrive S1 8x8, Chassis 8x8,NT & NTH 4×4
  • gear ratios - 19.97, 24.96, 32.83, 41.68, 51.0, R8.58
  • gear ratios - 2.2, 1.62 KOLOS & Hauler 6×6
  • Auxiliary gearbox - 2-speed electro-pneumatic control via switch on the gear lever and clutch pedal activated
  • gear ratio - 1.68
  • Step down transfer case - single
  • Planetary overdrive
  • ratios - 1.0, 0.62 KOLOS 8×8 & Hauler 6×6 only
  • Clutch - 3× plate dry clutch pedal hydraulic and air power assisted
  • - 2× plate dry clutch pedal hydraulic and air power assisted NT & NTH 4×4 only
  • 2× front and 2× rear 8×8 models
  • 2× front and 1× rear 6×6 models
  • 1× front and 1× rear 4×4 models
  • final drive ratio - 2.71
  • Differentials
  • 2.14 KOLOS 8×8
  • 2.12 Hauler 6x6 & S1 8×8
  • Planetary hub reduction ratios
                                     

2.4. Design and technology Brakes

Full triple circuit air "S" cam drum brakes acting on all wheels drums via slack adjuster, all brake cylinders were remotely vented. First brake circuit acts on front wheels, the second on rear wheels and the third controls trailer service brakes. Unique design feature was remotely mounted brake valve which was operated via hydraulic master and slave cylinder principle on the Hauler 6x6 or via mechanical linkage on 8x8 models.

  • Supplementary brake ----> exhaust brake electropneumatic brake
  • Park brake ----> mechanical via output shaft and drum at the back of the gearbox
  • Main wheel brakes ----> dual circuit drum brakes "S" cam type


                                     

2.5. Design and technology Bodywork

Cabin is all steel construction of COE design but not tiltable, the access to the engine was provided via removable engine cowlings inside the cabin compartment. The cab came in two versions, the "short" two-seater two-door version and in the "long" "crew cab" seven seater four-door version. The military specs cabs included the roof hatch or two in the case of the crew cab. All cabs were equipped with self-contained diesel cab heater which could also be used in the winter to warm up the engine before starting it. Another military feature was CTI central tyre inflation system controlled from the cab for each wheel independently and an ability to pressurize gearbox and differentials housing during water crossing. The 8x8 models had abilility to cross trenches up to 1.4 metre wide and vertical obstacles up to 0.6 metre high. Water crossing depth static including the wave was up to 1.4 metre KOLOS 8x8. The vehicle top speed was 92 km/h NT & NTH, 80 km/h KOLOS, 70 km/h hauler, 60 km/h S1 2000 engine rpm.

  • Vehicles Weights


                                     

3. Production

Production of Tatra T813 began in 1967 and was superseded by Tatra T815 in 1982. Models were available in the 4x4, 6x6, and 8x8 drive configurations for civilian and military use.

  • Primary models
  • Tatra T813 Cab-chassis 8x8 - Bodybuilders chassis for special use
  • Tatra T813 "KOLOS" 8x8 - Military heavy haulage
  • Tatra T813 NT & NTH 4x4 - Prime movers and special applications
  • Tatra T813 Hauler 6x6 - Civilian heavy haulage
  • Tatra T813 S1 8x8 - Heavy one way tipper
                                     

4. Sport

T813 has become extremely popular after fall of the Iron Curtain in the West as an extreme off-road truck, participating at the various truck trials held across Europe.

                                     
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  • power ranging from 230 440 kilowatts 310 590 hp As a successor to Tatra T 813 it was originally designed for extreme off - road conditions, while nowadays
  • 1980s both conventional Tatra T 148 and COE Tatra T 813 s were succeeded by the single line of COE Tatra T 815s. However Tatra aimed to develop a conventional
  • R - 330P, KRTP - 86 Tamara, GAZ - 46 MAV, Praga V3S, UAZ - 469, ZIL 131, Tatra 805, Tatra 813 Cold War: West featuring for example: Centurion, Chieftain, M47 Patton
  • self - propelled artillery gun to enter service. It is based on a modified 8x8 Tatra 813 chassis with excellent cross - country mobility. Currently it is in service
  • truck Tatra T 813 s central inflation and deflation system was designed to maintain pressure even after multiple bullet punctures. Military Tatra trucks
  • America, Asia and Europe. RM - 70 replaced the Ural - 375D 6x6 truck by a Tatra T 813 Kolos 8x8 truck as carrier platform for the 40 - round launcher. The new
  • otherwise similar. PM - 55 Prepravnik Mostu - Wheeled version, based on a Tatra 813 Kolos 8x8 truck. Belarus - MT - 55A Egypt - MT - 55KS Czech Republic
  • spreading from the middle Danube to the Dnieper and from Odrin to the Tatra Mountains. His able and energetic rule brought law and order to Bulgaria
  • military 6 6 chassis in the West. Vehicles of the Warsaw Pact, such as the Tatra 813 and MAZ - 535 series, were instead based on narrow backbone chassis with
  • of three Vert green hills, representing the mountain ranges trimount Tatra Matra, and Fatra made up of the Greater Fatra and Lesser Fatra ranges