CN103577650B - Thin plate large-scale fuel tank welding anti-distortion forming method - Google Patents

Abstract

The present invention relates to a kind of thin plate large-scale fuel tank welding anti-distortion forming method, solve employing prior art weld thin plate large-scale fuel tank welding deformation amount big, the problem that quality is not easily controlled.Comprise the following steps: calculate the deflection of postwelding according to known conditions, according to the deflection calculated, the size of fuel tank default anti-deformation before welding is designed, draw fuel tank actual production size before welding, making the fuel tank after welding meet design and require size, presetting deflection before weldering is: vertical directionHorizontal direction δ=△ Ltg θ, wherein θ is any point postwelding residual stress and the angle of its vertical direction component of F1 on weld seam, and R is arch welded joint radius, and N is fuel tank rigidity, and S is that section of weld joint amasss, including the area of heat affected area.The present invention provides clear and definite formula, and numerical computations is accurate, especially big to overall dimensions, the product that commissure number is many, can save expense and the time of a large amount of design frock.

Description

Thin plate large-scale fuel tank welding anti-distortion forming method

Technical field:

The present invention relates to the welding method of a kind of fuel tank, particularly to a kind of thin plate large-scale fuel tank weldering Connect reversible deformation forming method.

Background technology:

The large-scale fuel tank of thin plate of weld seam long for band circular arc, owing to its shape is complex, sheet material Thin, structure is complicated, and welding capacity is big, and fusion length is long, and deformation is big, is that welding is raw all the time Difficult point in product.After welding, entire length size is toward more much smaller than Design Requirement Drawing size, And it is also little than the radius that design requires to weld the radius of rear fuel tank arc.So this kind of fuel tank one The problem that directly there is qualification rate extremely low (almost without the most qualified)!Have a strong impact on product Quality.The measure preventing post welding distortion that current this kind of fuel tank is taked has: rigid fixation welds Connect, postwelding corrects, change the methods such as welding procedure.The size of postwelding can only be changed by these methods Become 1-2mm.The design requirement of product can not be met far away.

Summary of the invention:

The present invention, by providing the welding method of a kind of reversible deformation, solves employing prior art weldering Connect thin plate large-scale fuel tank welding deformation amount big, the problem that quality is not easily controlled.

The present invention is realized by techniques below scheme:

A kind of thin plate large-scale fuel tank welding anti-distortion forming method, comprises the following steps:

The deflection of postwelding is calculated, according to the deflection pair calculated according to known conditions The size of fuel tank default anti-deformation before welding is designed, and show that fuel tank is before welding Actual production size, makes the fuel tank after welding meet design and requires size, preset deflection before weldering Concrete calculating process be:

Carry out calculated below weld fuel tank when not setting welding anti-distortion amount in the case of:

Fuel tank arch welded joint is in the moment suffered by certain point:

DM=F1 × Rsin θ cos θ, wherein F1 is that on arch welded joint, any point postwelding remnants should The size of power and distribution arrangement, θ is the angle of F1 Yu F1 vertical direction component F 2, and R is Arch welded joint radius, quadratures and understands fuel tank side Moment:

Wherein θ 1 is fuel tank arch welded joint left and right end points The angle value of F1 Yu F2,Angle value for F1 Yu F2 on fuel tank arch welded joint summit；

Fuel tank entirety Moment:

Fuel tank in the deformation of vertical direction is:

$\mathrm{\ΔL}=2F1\×R{\∫}_{\mathrm{\θ}1}^{\frac{\mathrm{\π}}{2}}\sin \mathrm{\θ}\cos \mathrm{\θd\θ}/N$

In above formula, N is the integral rigidity of fuel tank

F1=σ 2 × S, wherein σ 2 is weld residual stress value, depends on welding rod material, can Tabling look-up from metal material handbook and draw, S is the sectional area of weld seam, including the area of heat affected area；

Fuel tank deformation in the horizontal direction is:

In δ=△ this formula of Ltg θ, δ-value is approximate calculation value, need to be according to producing reality slightly Revise；

△ L and δ (horizontal direction left end deflection δ 1 and the right-hand member deformation more than calculated Amount δ 2) as the reversible deformation value that should preset, design reality according to the two value graphing method Border produces figure and other relevant size.

The present invention provides clear and definite formula, eliminates the impact of welding deformation, numerical value with reversible deformation It is accurate to calculate, and low cost is especially big to overall dimensions, and the product that commissure number is many can be saved The expense of a large amount of design frocks and time.

Accompanying drawing illustrates:

Fuel tank welding residual stress distribution situation figure when Fig. 1 is not take reversible deformation；

Fig. 2 produces design drawing for reserved reversible deformation rear fuel tank.

Detailed description of the invention:

The welding of the large-scale fuel tank of thin plate of weld seam long for band circular arc, due to the contraction of weld seam, makes Welding residual stress must be dispersed with along bead direction.Its distribution situation is as shown in Figure 1: solid line is The profile that fuel tank requires, size L2 is the size of fuel tank requirement；Dotted line is generation after fuel tank welding Profile after deformation, size L1 is the size after fuel tank deformation, and δ 1, δ 2 are respectively the left side The size reduced with the right, f is produced amount of deflection after fuel tank is deformed, and power F1 is weldering The size of rear residual stress and distribution arrangement (along circular arc tangential line direction), power F2 is that power F1 exists It is perpendicular to the component (i.e. the vertical component of F1) in arm of force L direction.Dash area represents power F2 Size distribution situation.R is the radius of arc, and θ is the angle of F1 and F2.Δ L is that fuel tank hangs down Nogata is to deflection.

By upper figure it can be seen that fuel tank is in the moment suffered by certain point:

dM=F2×L---(1)

L=R×cosθ---(2)

F2=F1×sinθ---(3)

Can be obtained by (1), (2), (3):

DM=F1 × Rsin θ cos θ,

Quadrature and understand:

$M=F1\×R{\∫}_{\mathrm{\θ}1}^{\frac{\mathrm{\π}}{2}}\sin \mathrm{\θ}\cos \mathrm{\θd\θ}$ θ 1 is fuel tank arch welded joint left and right end The angle value of F1 Yu F2 of point,Angle for F1 Yu F2 on fuel tank arch welded joint summit Value；

Fuel tank entirety Moment:

If the overall rigidity of fuel tank is N,

Then fuel tank at the deformation distance that vertical direction is overall is:

$\mathrm{\ΔL}=2F1\×R{\∫}_{\mathrm{\θ}1}^{\frac{\mathrm{\π}}{2}}\sin \mathrm{\θ}\cos \mathrm{\θd\θ}/N$

In above formula, F1=σ 2 × S, wherein σ 2 is weld residual stress value, depends on welding rod Material, can table look-up from metal material handbook and draw, S is the sectional area of weld seam, including heat affecting The area in district；

Fuel tank deformation in the horizontal direction is:

In δ=△ this formula of Ltg θ, δ-value is approximate calculation value, need to be according to producing reality slightly Revise；

△ L and δ (horizontal direction left end deflection δ 1 and the right-hand member deformation more than calculated Amount δ 2) as the reversible deformation value that should preset, design reality according to the two value graphing method Border produces figure and other relevant size.

Fig. 2 produces design drawing for reserved reversible deformation rear fuel tank, after wherein dotted line is for reserved reversible deformation Profile, size L1 is the size after reversible deformation；Solid line is the profile that design requires, size L2 is the size of requirement, and δ 1, δ 2 are respectively the left side and the size of the right increase, and △ L is The size that reversible deformation is reserved in vertical direction.

Claims (1)

1. a thin plate large-scale fuel tank welding anti-distortion forming method, is characterized in that: include following step Rapid:

The deflection of postwelding is calculated, according to the deflection pair calculated according to known conditions The size of fuel tank default anti-deformation before welding is designed, and show that fuel tank is before welding Actual production size, makes the fuel tank after welding meet design and requires size, and presetting before welding is anti- The concrete calculating process of deflection is:

Following meter is carried out in the case of welding fuel tank during default anti-deformation before not setting welding Calculate:

Fuel tank arch welded joint is in the moment suffered by certain point:

DM=F1 × Rsin θ cos θ, wherein F1 is that on arch welded joint, any point postwelding remnants should The size of power and distribution arrangement, θ is the angle of F1 Yu F1 vertical direction component F 2, and R is Arch welded joint radius, quadratures and understands fuel tank side Moment:

Wherein θ 1 is fuel tank arch welded joint left and right end points The angle value of F1 Yu F2,Angle value for F1 Yu F2 on fuel tank arch welded joint summit；

Fuel tank entirety Moment:

Fuel tank in the deformation of vertical direction is:

In above formula, N is the integral rigidity of fuel tank；

F1=σ 2 × S, wherein σ 2 is weld residual stress value, depends on welding rod material, can Tabling look-up from metal material handbook and draw, S is the sectional area of weld seam, including the area of heat affected area；

Fuel tank deformation in the horizontal direction is:

In δ=Δ this formula of Ltg θ, δ-value is approximate calculation value, need to be according to producing reality slightly Revise；

Δ L and δ more than calculated is as the reversible deformation value that should preset, and δ represents level Direction left end deflection δ 1 and right-hand member variable δ 2, according to Δ L and δ the two value graphing method Design actual production figure and other relevant size.