What is zig zag riveted lap joint?
When multiple joints are used, the arrangement of rivets between two neighbouring rows may be of two kinds. In chain riveting the adjacent rows have rivets in the same transverse line. In zig-zag riveting, on the other hand, the adjacent rows of rivets are staggered. Fig. 2.3 Lap joint.
What is double riveted lap joint?
Double Riveted Joints can be of Lap type or Butt Type. In Double Riveted Lap Joints, there are two lines of rivets between the main plates used to create a joint. In Double Riveted Lap Joints, there are two lines of rivets in each main plate and cover plate combinations.
Which of the following riveted butt joint with double straps should have the highest efficiency as per Indian boiler regulation?
As the maximum stress developed along the circumferential direction, the longitudinal joint in the boiler should be stronger than the circumferential joint. Hence the longitudinal joint in the boiler is usually butt joint with two cover plates and circumferential joint is lap joint.
What is thickness of cover plate TS If thickness of main plate T is used for single rivet double strap butt joint?
Average thickness of double cover plate butt joint is 0.75 times that of main plate. Clarification: Thickness of cover plate in a double cover plate butt joint is about 0.7 to 0.8.
What is the difference between lap joint and but joint?
Lap joint: In lap joint, plates overlapped each other. The rivets are inserted in the overlapped region. Butt joint: In this type of riveting, the plates to be joined is kept in alignment butting/ touching, without forming an overlap.
What are the types of lap joints?
5 Types of lap joints
- Basic lap joint. In a basic lap joint, the boards are simply cut to length and lapped over each other, with a few fasteners in the middle to hold them together.
- Half-lap joint.
- Mitered lap joint.
- Cross-lap joint.
- Dovetail lap joint.
Which of the double butt joint used in boiler shell has highest efficiency?
Which double wrist butt joint used in boiler shell is highest efficiency?
longitudinal joint
Solution: The longitudinal joint in a boiler shell is usually Butt joint with two cover plates this joint is more efficient than lap joint.
How do you calculate rivets?
The length of the rivet should be equal to the thickness of both objects you are fastening, plus 1.5 times the diameter of the rivet’s stem. 3/32” (2MM) FOR UP TO 3/32” (2MM) THICKNESS. 1/8” (3MM) FOR UP TO 1/8” (3MM) THICKNESS.
How do you calculate rivet value?
For plates working stress in axial tension =156 N/mm2. The strength of a rivet in shearing and in bearing is computed and the lesser is called the rivet value (R). Hence the Rivet value is 86.75 kN. Number of rivets required to transmit pull of 750 kN n= (750/86.75) = 8.67 ≈ 9 rivets.
What is the difference between lap and a butt riveted joint?
What are 4 types of lap joints?
Half lap, mitred half lap, cross lap and dovetail lap are the four most commonly used forms of the lap joint. Each style has a cut characteristic that makes it easily identifiable.
What is a lap joint flange?
A lap-joint flange is a two-component assembly, with a stub end that has a lap-joint ring flange placed over it. The stub end is then butt welded to the pipe, and the flange ring can be rotated to align with the mating flange. This type of flange connection is particularly useful for large or hard-to-adjust flanges.
What is the strength of riveted joint?
∴ The strength of a riveted lap joint is equal to its least of shearing strength, bearing strength and tearing strength. ∴ The strength of a riveted lap joint is equal to a minimum of PT, PS, and PB.
What is the diameter of rivets?
The proper diameter rivet would be 3 x 0.060=0.180 inches. A 3/16” rivet (0.188 inches) should be used. The metal thickness is 0.060+0.060=0.12 inches, and 1.5D is 1.5 x 0.188 inch = 0.282 inches, so the total length would have to be 0.12 + 0.282=0.402 inches for the rivet.
What is the recommended edge distance for a rivet?
The minimum edge distance for universal rivets is 2 times the diameter of the rivet; the minimum edge distance for countersunk rivets is 2.5 times the diameter. If rivets are placed too close to the edge the sheet may crack. If they are spaced too far the sheet is likely to turn up at the edges.
What is bearing strength of rivet?
Strength of rivet in double shear = Strength of rivet in bearing = D x t x pb = 23.5 x 12 x 300/1000 = 84.6 kN. The strength of a rivet in shearing and in bearing is computed and the lesser is called the rivet value (R). Hence the Rivet value is 84.6 kN.
What is nominal diameter of rivet?
The diameter of a rivet hole is equal to the nominal diameter of the rivet plus 1.5 mm for rivets nominal dia up to 25mm, and 2mm for rivet nominal dia above 25mm.
What are the advantages of a lap joint?
Advantages of lap joints include: Easy to prepare (does not require cut faces to be parallel or perfectly flat) Can be formed between two dissimilar metals, such as aluminum and copper. Accommodates different thicknesses (thinner piece must be welded on top)
Why is butt joint preferred over lap?
D. Explanation: double cover butt joint preferred over single cover butt joint or lap joint because (i) eccentricity of load is eliminated, hence no bending in bolts, (ii) total shear force to be transmitted is split into two parts, hence bolts are in double shear.
They’re a two-part flange consisting of a Lap Joint Stub End which is butt welded to the pipe and a backing lap joint flange which is slid onto the pipe before welding the Stub End. Lap Joint flanges are very similar to Slip On flanges.
What is the difference between lap joint stub ends and rolled angle rings?
Rolled Angle Rings — also known as Vanstone Rings or Vanstone Rolled Angle Rings — offer comparable benefits to Lap Joint Stub Ends with similar designs and installation requirements. However, there are subtle differences that will often make one preferable over the other in most cases.
What is a stub end flange?
These flanges are available in common dimensions like other flange types making it easy to integrate them into existing piping systems or use alongside other piping components. Stub Ends also match both pipe material and wall schedule to maintain both inside and outside diameters of your piping process.