TRA Series leaf spring for light duty trailer in North American market:
TRA Leaf Spring features:
1. This TRA LEAF SPRING work as a linkage for holding the axle in position and thus separate suspension are not
necessary. It makes the construction of the suspension simple and strong.
2. Because the positioning of the axle is carried out by the leaf springs, it is disadvantageous to use soft springs,
And soft springs with low spring constant.
3. Therefore, this type of TRA leaf spring suspension does not provide good riding comfort, because of the inter-leaf friction between the leaf springs affects the riding comfort.
4. Acceleration and braking torque cause wind-up and vibration. Also wind-up causes rear-end squat and nose-
diving.
5. The inter-leaf friction damps the spring’s motion and reduces rebound, which until shock absorbers were widely
adopted was a great advantage over helical springs.
TRA series OEM part numbers for reference:
S/N | OEM | Type | No. of Leaf | Weight | Material section |
(kg) | (mm) | ||||
1 | TRA2726 | Parabolic | 3 | 26.27 | 20 X 76 |
2 | TRA2727 | Parabolic | 3 | 25.83 | 20 X 76 |
3 | TRA2728 | Parabolic | 3 | 25.59 | 20 X 76 |
4 | TRA3343 | Conventional | 10 | 69.02 | 11 X100 |
5 | TRA2705 | Conventional | 7 | 44.83 | 13 X 75 |
6 | TRA2260 | Conventional | 8 | 48.6 | 13 X 75 |
7 | TRA2256 | Conventional | 7 | 41.21 | 13 X 75 |
8 | TRA3319 | Conventional | 9 | 53.17 | 13 X 75 |
9 | TRA2297 | Conventional | 9 | 51.71 | 13 X 75 |
10 | TRA2270 | Conventional | 8 | 49.82 | 13 X 75 |
11 | 83-115 | Conventional | 14 | 54.6 | 10 X 75 |
12 | TRA2752 | Parabolic | 2 | 25.68 | 24 X 76 |
13 | TRA2754 | Parabolic | 2 | 25.35 | 24 X 76 |
14 | TRA2740 | Parabolic | 3 | 31.03 | 24 X 76 |
15 | TRA2741 | Parabolic | 3 | 30.8 | 24 X 76 |
16 | TRA021 | Parabolic | 1 | 18.5 | 35 X 76 |
17 | TRA023 | Parabolic | 1 | 18.58 | 35 X 76 |
18 | TRA699 | Parabolic | 4 | 29.86 | 20 X 76 |
19 | S1-52 | Parabolic | 4 | 34.56 | 20 X 76 |
20 | TRA693 | Parabolic | 3 | 25 | 20 X 76 |
21 | TRA038 | Parabolic | 1 | 22.31 | 40 X 76 |
22 | TRA035 | Parabolic | 1 | 18.04 | 35 X 76 |
23 | 55-896 | Conventional | 8 | 68.8 | 11 X 100 |
24 | TRA3340 | Parabolic | 3 | 29.6 | 20×76 |
25 | TRA2291 | Parabolic | 3 | 27.27 | 20×76 |
26 | 55-1192 | Parabolic | 4 | 38.68 | 18,8×100 |
27 | 59-400 | Parabolic | 3 | 73.26 | 22×100 |
28 | 62-830 | Parabolic | 4 | 50.4 | 8,18×90 |
29 | M/C 3 1/2"x1/2" | Conventional | 9 | 13*90-9 | |
30 | M/C 4 x 1/2" | Conventional | 9 | 13*100-9 | |
31 | 46-220 | Parabolic | 3 | 18(8)*100-4 | |
32 | 46-1280 | Parabolic | 2 | 20(14)(8)*100-5 | |
33 | 55-067 | Parabolic | 1 | 33*90-1 | |
34 | ZZ03 | Parabolic | 38*90-1 | ||
35 | 55-430 | Parabolic | 18(6)*100-5 | ||
36 | 16710-01 | Parabolic | 2 | 35*76-2 | |
37 | TRA2160 | Conventional | 8 | 48.3 | 13 X 75 |
38 | TRA696 | Conventional | 9 | 51.03 | 13X 75 |
39 | 55-144 | Parabolic | 5 | 48.78 | 8,10,21×100 |
40 | TRA693 | Parabolic | 3 | 26 | 20×76 |
41 | TRA1492 | Parabolic | 3 | 30 | 20×90 |
42 | TRA3341 | Parabolic | 3 | 26.2 | 20×76 |
43 | 62-147 | Conventional | 10 | 167 | 102*20，25 |
1. Production : | TRA series leaf spring for light duty trailer, boat trailer, |
Size: 76x20, 75x13, ... | |
2. Leaf spring types: | Conventional Leaf Spring, Parabolic Leaf Spring, Z Type Air linker, TRA leaf spring |
Trailer leaf spring, semi trailer leaf spring, Pickup leaf spring, sprung drawbar, Farm trailer spring | |
Truck lea spring, Bogie leaf springs, boat trailer leaf springs, Agricultural trailer leaf spring | |
3. Spring thickness and width: | Thickness from 6 mm to 50 mm, width from 44.5 mm to 120 mm |
4. Components: | Spring leaf, clip, center bolt, nut, bushing, |
5. Color | Red, shinning black, dark black, grey, blue, As requirement. |
6. Steel Flat Bar Materials Grade: | SUP6, SUP7, SUP9, SUP9A, SUP10, SUP11 and SUP11A are available. |
7. Leaf Spring Quality: | WONDEE exported leaf springs since 1999, We provide 24 months quality assurance. |
8. Related Certificate: | ISO9001; TS16949; COC; PVOC; CIQ; SONCAP; BV; C/O; FORM E. |
9.Leaf spring Application: | BENZ, VOLVO,TOYOTA, HONDA, NISSAN,MAN, HOWO, CIMC, ETC. |
10. Production ability: | 20000 Tons per month |
11. Packing | Wooden pallet |
12. Lead time: | About 10~15 Working Days |
What's the leaf spring ?
Leaf Spring is one of cells in auto suspension system, the main function is transmitting all force and moments between wheels and car frame, relax impactive load caused by the road surface and realize vehicle guidance, makes vehicles normal drive. It is a necessary component of truck, trailer, special cars and other vehicles.
The main three styles of leaf springs:
1. Multi-Leaf Spring – This type of leaf spring has more than 1 leaf in its assembly. It consists of a center bolt that properly aligns the leaves and clips to resist its individual leaves from twisting and shifting.
2. Mono Leaf Spring – Consists of one main leaf where the material’s width and thickness are constant. Example – the leaf will be 2 1/2" wide throughout its length, and .323 in thickness throughout its entire length. The spring rate is lighter than other styles of leaf springs and usually requires a device to control positive and negative torque loads as well as requiring coil springs to hold the chassis at ride height.
3. Parabolic Single Leaf – Consists of one main leaf with a tapered thickness. This style is sufficient to control axle torque and dampening, while maintaining ride height. The advantage of this style is that the spring is lighter than the multi-leaf.
The function of automobile leaf spring:
1. Holding the chassis at ride height
2. Controls the rate at which the chassis rolls
3. Controls the rear end wrap up
4. Controls axle dampening
5. Controls lateral forces such as side load, pan hard, or side bite rate
6. Controls brake dampening forces
7. Sets wheel base lengths during acceleration and deceleration
The maintaining and servicing about the leaf spring:
1. After driving a certain mileage, U-bolt of leaf spring should be screwed, in case of such accidents as malposition of the leaf spring, aberrancy of the car or the breakage from center hole which can all be caused by the loosing of the U bolt.
2. After driving a certain mileage, eye bushing and pin should be checked and lubricated in time. If bushing is badly worn, it should be replaced in order to avoid the eye sending out noise. At the same time ,such phenomena as the distortion of leaf spring and aberrancy of the car caused by the imbalanced wear of the bushing can also be avoid.
3. After driving a certain mileage, the assembly of leaf spring should be replaced in time, and leaf spring of both sides should be checked to see if there is any disaccord between both sides camber in order to avoid wear of the bushing can also be avoided.
4. As for new car or those with newly replaced leaf spring car, U-bolt should be checked after every 5000 kilometers' driving to see if there is any loose it loose. During driving, much attention should be paid to some unusual sound from the chassis, it may be the sign of dislocation of leaf spring or the loose of U-bolt or the breakage of the leaf spring?
Features of WONDEE TRA series Leaf springs:
1. High level of precision in finished product dimensions due to the use of automatic equipments .
2. More than 20 years experience in leaf spring , There have many part sizes and load capacities for optional.
3. Due to the Strong technical team and R&D capabilities, OEM Specifications are available
4. Wide range of models and configurations due to the Product accumulation since 1999
5. Reliability in the performance under the Strict product quality inspection
6. Optimization of weight under the Optimized product design
7. Raw Material of excellent quality from our partner steel mill
8. Innovation in processes with exclusive technology under our experienced engineers
WONDEE TRA series Leaf spring Production processing:
1: Spring steel flat bar, 2. Spring cutting, 3. Spring straightening, 4. Spring hole drilling, 5. Spring eye rolling, 6. Spring quenching, 7. Spring tempering, 8. Spring assembling, 9 Spring painting, 10, Spring mark making.
WONDEE supply various kinds of leaf spring more than 20 years:
In addition to supplying different types of light duty TRA leaf spring, WONDEE also Supply different types of semi trailer components as below: