Kweld Schematic
Prince Aboubakar
I might eventually build a supercapacitor power source for the kweld. What would I need to put between the boost capacitors and the kweld, if I want to protect capacitors from inductive voltage spikes - some sort of TVS?
Welding seams are crucial in ensuring the strength and integrity of metal structures, but do you know the different types and their symbols? This article provides a comprehensive overview of the various welding seam types, from butt welds to fillet welds, and explains the standard symbols used in engineering drawings. By understanding these symbols and their corresponding process codes, welders and engineers can improve their project accuracy and efficiency. Dive in to learn how mastering these basics can enhance your welding projects and prevent common pitfalls.
BlogLast updated:June 28, 2024Share your like:Table Of ContentsThere are no headings in this document.A weld seam refers to the joint part formed in the welded component after welding. The metal that makes up the weld seam, i.e., the weld metal, directly affects the performance of the welded components and structures due to its shape and quality. Therefore, welders should understand the types of weld seams and their representation symbols on engineering drawings.
A weld seam welded between the bevel surfaces of the workpieces or between the bevel surface of one part and the surface of another part.2) Fillet weld.A weld seam welded along the intersection line of two orthogonal or nearly orthogonal parts.
Two parts are overlapped, one of which has a round hole, and the weld seam formed by welding the two plates in the round hole, only the fillet weld inside the hole is not considered a plug weld.5) Slot weld seam.Two plates are overlapped, one of which has a long hole, and the weld seam formed by welding the two plates in the long hole, only the fillet weld is not considered a slot weld.
(2) According to the different spatial positions of the weld seamCan be divided into flat weld seam, vertical weld seam, horizontal weld seam, and overhead weld seam four forms.(3) According to the different continuity of the weld seam
Divided into load-bearing welds that bear loads, connecting welds that do not directly bear loads but only serve to connect, sealing welds mainly used to prevent fluid leakage, and positioning welds that are welded before formal welding to assemble and fix the position of joints on the workpiece with a shorter length.(5) According to the shape of the weld and its position at the jointDivided into butt welds that form butt joints; edge welds applied at the edge rolling of the workpiece; plug welds formed by welding in a round hole opened in one of two overlapped plates; circumferential welds distributed along the circumference of spherical or cylindrical workpieces with ends joined together; and flush welds whose surfaces are ground to be flush with the surface of the base material, etc.
In the cross-section of the welded joint, the depth of melting of the base material is called penetration depth, as shown in Figure 2-53. When the filler metal material (welding rod or wire) is fixed, the size of the penetration depth is determined by the chemical composition of the weld.
In the cross-section of the weld, the distance from the front of the weld to the back of the weld is called the weld thickness, as shown in Figure 2-54.Figure 2-54 Weld thickness of a butt weld(5) Shape and size of fillet weldsBased on the external shape of the fillet weld, fillet welds can be divided into two types: fillet welds with a raised surface are called convex fillet welds; fillet welds with a concave surface are called concave fillet welds, as shown in Figure 2-55. Under certain conditions, concave fillet welds have much less stress concentration than convex fillet welds.
a) Convex fillet weld
b) Concave fillet weld1) Weld calculation thickness.Draw the largest right-angled isosceles triangle within the cross-section of the fillet weld, the perpendicular length from the right-angle vertex to the hypotenuse is the weld calculation thickness. If the cross-section of the fillet weld is a standard isosceles right triangle, then the weld calculation thickness is equal to the weld thickness; in convex or concave fillet welds, the weld calculation thickness is less than the weld thickness.
4) Weld leg.In the cross-section of a fillet weld, the minimum distance from a weld toe on one workpiece to the surface of another workpiece; the weld leg size is the length of the right-angle side in the largest isosceles right triangle drawn in the cross-section, for convex fillet welds, the weld leg size is equal to the weld leg; for concave fillet welds, the weld leg size is less than the weld leg.
(6) Weld formation factorDuring welding, the ratio of the weld width (B) to the calculated thickness of the weld (H) on the cross-section of a single weld seam (ψ=B/H) is called the weld formation factor, as shown in Figure 2-56. The smaller the weld formation factor, the narrower and deeper the weld, which makes it prone to porosity, slag inclusion, and cracking. Therefore, the weld formation factor should maintain a certain value, for example, the weld formation factor for submerged arc welding should be greater than 1.3.Figure 2-56 Calculation of the Weld Formation Factor(7) Fusion Ratio
Where:
- y is the fusion ratio, %;
- F m is the cross-sectional area of the melted base material, mm 2 ;
- F H is the cross-sectional area of the melted filler metal, mm 2 .
Note: When welding double-sided welds or joints, basic symbols can be combined, see Table 2-15.Table 2-15 Combination of Basic SymbolsNo.SymbolDiagramAnnotation Example1Double-sided V-groove weld (X-weld)2Double-sided single V-groove weld (K-weld)3Double-sided V-groove weld with a blunt edge4Double-sided single V-groove weld with a blunt edge5Double-sided U-groove weld3. Supplementary SymbolsSupplementary symbols are used to provide additional information about certain characteristics of welds or joints (such as surface shape, backing, weld distribution, welding location, etc.).
1) See Table 2-16 for supplementary symbols.Table 2-16 Supplementary SymbolsNo.NameSymbolDescription1FlatThe weld seam surface is usually machined to be flat.2ConcaveThe weld seam surface is recessed.3ConvexThe weld seam surface protrudes.4Smooth TransitionThe transition at the weld toe is smooth.5Permanent BackingThe backing is permanently retained.6Temporary BackingThe backing is removed after welding is completed.7Three-Sided WeldThe weld is present on three sides.8Peripheral WeldA weld applied along the perimeter of the workpiece; the location is marked at the intersection of the baseline and the arrow line.9Field WeldA weld executed on-site.10TailCan indicate the required information.2) Tables 2-17 and 2-18 provide examples of the application and marking of supplementary symbols.
The datum line should generally be parallel to the bottom edge of the drawing, but can also be perpendicular if necessary. The positions of solid and dashed lines can be interchanged as needed. When marking symmetrical welds or double-sided welds, dashed lines can be omitted.
When it is necessary to simply draw welds in the drawing, they can be represented by views, sectional views, or cross-sectional views, or can be schematically represented by isometric drawings.1. ViewWhen representing welds with a view, the drawing method is as shown in Figure 2-59, where the welds represented by Figure 2-59a and b series of solid lines are allowed to be drawn by hand; the weld represented by Figure 2-59c is indicated with a thick line.
In the view representing the weld surface, the outline of the weld is usually drawn with a thick solid line. If necessary, the shape of the bevel before welding can be drawn with a thin solid line, as shown in Figure 2-60.
In a sectional view or cross-sectional view, the metal fusion zone of the weld is usually shaded in black, as shown in Figure 2-61a. If it is also necessary to represent the shape of the bevel, etc., the fusion zone part is usually outlined with a thick solid line, and if necessary, the shape of the bevel before welding is drawn with a thin solid line, as shown in Figure 2-61b.Figure 2-61 Sectional (surface) view representing the weld3. Isometric drawingThe method of representing welds with an isometric drawing is as shown in Figure 2-62.
4) The quantity of identical welds is labeled at the end.5) When there are many dimensions that are difficult to distinguish, the corresponding dimension symbols can be marked in front of the dimension data.
7) When there are no dimension markings on the right side of the basic symbol and no other instructions, it means that the weld is continuous along the entire length of the workpiece.8) When there are no dimension markings on the left side of the basic symbol and no other instructions, it means that the butt weld should be fully penetrated.
The method of marking weld dimension symbols is shown in Figure 2-64.Figure 2-64 Method of marking weld dimension symbols3. Common weld dimension symbolsThe common weld dimension symbols are shown in Table 2-19.Table 2-19 Common Weld Seam Size Symbols
A small flag represents a field or on-site weld, as shown in Figure 2-66.Figure 2-66 Annotation of Field Weld5. Application of Weld Seam Symbol Size AnnotationThe application of weld seam symbol size annotation is shown in Table 2-20.No.NameDiagramDimension SymbolAnnotation Method1Butt WeldS: Effective Thickness of Weld2Continuous Fillet WeldK: Size of Weld Leg3Intermittent Fillet WeldI: Weld Length
e: Spacing
n: Number of Weld Segments
K: Size of Weld Leg4Staggered Intermittent Fillet Weldl: Weld Length
e: Spacing
n: Number of Weld Segments
K: Size of Weld Leg5Plug Weld
or
Slot Weldl: Weld Length
e: Spacing
n: Number of Weld Segments
c: Slot Widthe: Spacing
n: Number of Weld Segments
d: Hole Diameter6Spot Weldn: Number of Weld Spots
e: Distance Between Weld Spots
d: Fusion Core Diameter7Seam Weldl: Weld Length
e: Spacing
n: Number of Weld Segments
c: Weld WidthV. Simplified notation method for weld symbolsThe simplified notation method for weld symbols is shown in Table 2-21.