Round Fitting Fab Flashcards
Try not to get fucked.
To brake a transitional brake on an elbow, the amount of angle is measured with a protactor.
TRUE or FALSE
FALSE
Why must s Slip and Drive joint be adjusted on transitional fittings?
The 1” S-cleat CANNOT be at an angle to the next fitting.
Why do we leave the gore sections together for rolling?
Avoid rolling the pieces to different curvatures
When devloping the piece for a 2 side flat transition, what should determine which sloped side gets to pocket allowance and WHY?
The side that has the most amount of slope.
Because there is less angle for transfer of angle notch.
When assembling a transitional fitting, what should be done before assembly?
- Forming seams and edges
- Open Pittsburgh Locks
Why is the use of transitional fittings avoided?
- Time
- Money
What should you do to the metal of the body before folding the hooks for the grooved seam?
Before folding the hooks for the grooved seam, the ends of the material should be pre-rolled slightly so that the pipe ends up round with no flat spots at the seam.
What is the 2 pruposes of a Bead Seam on round pipe?
- As a stop to keep the big end of the next pipe from sliding down too far
- Strengthening and stiffening the pipes
Define Transitional Fitting
A fiiting that changes size of both dimensions.
How should the small end of a round project be identified?
The best way to identify the small end is with a small end notch.
What can be done to remove the possibility of the grooved seam collapsing?
- Center punch the seam at the bead
- Spot weld the seam at the bead
- Put a rivit throught the greooved seam at the bead
Why are Offset fittings used instead of 2 Elbows?
The Offset is used to move the duct line over a specific amount.
What are the measurements necessary to choose a pattern for an elbow?
- Opening Size
- Throat Radius
- Elbow Angle
Descride the notch used on the spot welded lap elbow or offset.
The notch is the removal of material where the 2 lap allowances over lap.
It is basically a square notch, with a slight relief on the longitudinal seam allowance
What is used to indicate weld type on the blueprint?
Welding symbols
Are round elbows laid out with a large end and a small end?
TRUE or FALSE
TRUE
They are laided out with a large end and a small end.
Why do we try to make the duct ratio as low as possible?
With a low ratio of lenght to width moves air more efficiently than large ratio.
Why is it necessary to number the plan views and the patterns properly?
If the element lines in both views are not numbered correctly, the miter line will not be correct.
What causes porosity?
Contamination of the weld
Testing to see if a pipe is the correct size should be done when?
After the completing the longitudinal seam.
If a transtional fitting is not possible to use, what are your options?
- Change the duct size to something equivalent that does not require a transitional fitting.
- Accomplish the transition in 2 fittings. This is not recommended in medium to high high pressure systems do to turbulence, noise and pressure drop.
The strechout length of a heel runner should be determined by which method.
- Calculated
- Measured
Calculated
Pattern development in the shop differs from the Pattern Development room only in the tools used.
TRUE or FALSE
TRUE
welding a tee joint, a lap joint, and the inside of a corner joint all require the _______ weld type
Fillet
What is the formula to calculate the stretch-out of the cylinder?
3.14 (pie) X diameter of the cylinder
Why would blocking be used when assembling a transitional fitting with raw edges?
To keep the assembly edge flat and not damaged the fitting.