Welding procedures

Posted in: , on 12. Mar. 2007 - 09:32

This is from analysis we need to know the procedure of welding of two plates.

condition:existing thickness of plate is 25mm this is to be splitted up to 12.5mm& 12.5mm

Load is, this plate is in bottom plate of structure weight around 1 ton (of L shape structure)

Just fasteners is enough? or weld is needed thro out the plate?

or only bore weld is sufficient?

What is theoretical calculation procedure?any related material, sites etc.




Posted on 12. Mar. 2007 - 03:43

Unfortunately you cannot ask a question ike this with out more backround regarding the application.

You need to tell us more regarding the application, steel type, etc.


Posted on 13. Mar. 2007 - 10:09


Concerning about my problem generally it is not wise to post this question,general curiosity i am asking we have to use 25mm thik plate for one particular application.In that place instead of 25mm single plate can we use 12.5mm + 12.5mm on weldable condition?



Welding Etc.

Posted on 13. Mar. 2007 - 02:58

Greetings and salutatiions from the "Frozen Eastern Wilderness

@ 1140 feeet above mean sea level Prakash.

(For this application I will assume that the plate steel is to be

attached on its edges-(the perimeter).

The only bad thing about lapping plates together is rust and that

it will eventually eat through the steel unless it is painted with

(rust-oleum) or another brand of paint.

If the weldments are stationary-(not used in a screener) you can

use a lap plate configuration to do this but you must be sure to

bolt the plate together with grade 8 or stronger fine threaded

allen head cap screws and be sure to use nylock nuts (nuts with

nylon locking inserts or grade 8 fine threaded nuts with threads

locker such as (Loc-Tite red) and (allen head spring washers-

compression washers) for both sides of the steel plate-do not

use a regular spring washer (compression washer) as they will

fail-due to the difference in diameters of the bolt shank) the bolts

should be torqued as well to a lubricated thread value-newton


The bolt holes should be no further apart than 15 centimeters on

center as well using an 8-12 diameter SAE millimeter bolt

extending two and one half centimeters past the thickness of the

steel sheet if you have the clearance.

Re: Welding Procedures

Posted on 14. Mar. 2007 - 05:17

Hai lzaharis

Thank u very much for ur immediate response.

Is there any standard available for this intended application(for lap welding). We hesitate to use this type of welding joint because there is no recommendation available in any general mechanical hand book. How to calculate welding strength in this structure.


**Bottom plate is 25mm thick (going to be splitted 13+12mm)

**Type of Load acting on the above plate = compression load (1000kgf)+ moment(18000N-m)




Posted on 14. Mar. 2007 - 04:48

Greetings Prakash,

Developing a weldment for your application is not difficult as it can be done either by a robot welder or manually, a machine weld id preferable as quality is constant and continous as it will consist of two single pass fillet welds due to the thin plates ands will not overheat.

High carbon steel/attack resistant plate is an absolute necessity for your apllication. `

To maintain a quality weld the steel will have to be tack welded manually along the entire length to eliminate the possiblity of heat distortion from the main welding operation.

("Another even better option is hot riveting the plates together bypassing the need for welding entirely")

gusssets should be welded or hot riveted to join the plates together at the 90 degree angle as a matter of principle as well to guarantee the integrity of the joint.

Before any welding is done the plates should be bolted together as I previously have suggested the only thing I would change is using fine threaded nuts without nylock inserts and "Loctite" if you insist on welding the plates.

If you investigate this further you will find that the allen head fine threaded bolts bolted through the plates will be more than adequate for your application in my opinion though.

The bad thing about using two plates to do this is corrosion and its effects where using a single plate reduces total weight and materials and you only have one sheet of steel to contend with.

Re: Welding Procedures

Posted on 19. Mar. 2007 - 07:13

You can find what you seek in many weldment manuals. Two such manuals on welding configuration of all types are:

1. Design Of Weldments: by Omar Blodgett

published by James F. Lincoln Arc Welding Foundation

2. Design of Welded Structures: same references as per pt. 1.

Lincoln welding is the largest supplier (or was) of arc welding equipment in the USA.

Lawrence Nordell Conveyor Dynamics, Inc. website, email & phone contacts: www.conveyor-dynamics.com nordell@conveyor-dynamics.com phone: USA 360-671-2200 fax: USA 360-671-8450