This spring assy are widely used in Thailand for trailer suspension parts .
Spring Measurements Specs
Totally 9 blades ,1-9 blade Width(mm)*Thickness(mm): 76*14, End to End Measurement 1210 mm (Free Length Measurement),Tolerance range within ±3mm . Free Arch Measurement (see picture) 110mm,Tolerance range within ±5 mm . hook on left of the 3rd blade .
All datas are obtained by measuring the new produce product .
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Trailer Leaf Spring Process
Multi-leaf springs are made as follows:
1.Shearing of flat bar
2.Center hole punching / Drilling
3.End Heating process
(1).Eye Forming / Wrapper Forming forming (hot & cold process)
(2).Diamond cutting / end trimming / width cutting / end tapering
(3).End punching / end grooving / end bending / end forging / eye grinding
(4).Center hole punching / Drilling / nibbing
4.Heat Treatment
(1).Heating
(2).Camber forming
(3).Quenching
(4).Tempering
5.Surface preparation
(1).Shot peening / stress peening
(2).Painting
6.Eye bush preparation process
(1).Eye reaming / eye boring
(2).Bush insertion
(3).Bush reaming
7.Assemble
(1).Presetting & load testing
(2).Paint touch-up
(3).Marking & packing
Finished Products and Pack Photos
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Key Points Keep The High Quality
1) Raw matrail . |
Thickness less than 20mm. we choose SUP9/55Cr3/SAE5160H as the product material |
Thickness from 20-30mm. wE choose SUP11A/50CrVA |
Thickness more than 30mm. We choose 51CrV4 as the raw material |
Thickness more than 50mm. We choose 52CrMoV4 as the raw material |
2) Quchenging Process |
We strickly controled the steel temeprure around 800 degree. |
we swing the spring in the qenching oil among 10 seconds according to the spring thickness. |
3)Shot Peening. |
Each assmembing spring set under stress peening . |
Fatigue test can reach over 150000 cycus |
4) Painting |
Each leaf under cataphoresis painting. |
Salt spray testing reach 500hours |
Production Process
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1.Material Cutting
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4.Edge Cutting
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7.Stress Peening
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2.Punching
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5.Quenching
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8.Assembling
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3.Eye Rolling
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6.Tempering
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9.Painting
FAQ
Q1: What type of leaf spring could you produce ?
A: We can produce most kinds of springs in the market. especially on the parabolic springs.
Q2: What material could you supply for leaf spring?
A: Our material grade should be SUP9/SUP9A /SUP11A/51CrV4 /52CrMoV4/ even 55Cr3 and SAE5160H as well .
Q3: How long will be your delivery time?
A: 20-40days. If material stock enough around 20days. if not,would be 40days
Q4: What payment terms are acceptable?
A: TT and LC at sight
Q5: What is the packing?
A: No fumigation wooden pallet . we also can pack according to whatever you request if reasonable.
Q6:How about the surface finishing ?
A : electrophoresis coating (black,red,gray,or as customer’s requests )