"Del Johnson, North Point Solutions, Inc" wrote:
I contacted a company (Shapiro Supply Co, St. Louis, MO) that I have ordered
small quantities of aluminum tubing and asked if they could supply Inconel
625 tubing and whether they would handle a group purchase (i.e. receive
orders, credit card numbers from each person in the group, get the material
from their supplier and cut it up, package and ship to each person in the
group the quantity that they requested).
For purposes of pricing I told him to assume that we could get a group order
for 100' of 2" - 0.035 wall thickness 625 Inconel. He came back with the
following quotes
If he purchased 100' of tubing in 20 foot lengths he could sell it to us at
$55/foot. However, he would have to cut up the Inconel into pieces such
that there would be no waste. This goes for all the other quotes which
follow. It would take his supplier about 6 weeks to deliver since they do
not have the 20 foot lengths in stock.
He could get his hands on 10' lengths of the same material within a week.
However the price per foot for a 100 foot order is 78.50. In other words he
can get the 20' length tubing quite a bit cheaper than the 10' length
tubing.
He also quoted a price of $92.25 for a 40 foot quantity order, assuming we
only can mobilize a small group purchase. This material at this rate would
come in 10 foot sections which he would cut up to whatever size each
individual in the group needs.
Again, he cannot realize cost of any wastes.
To compare these prices to straight 2" Stainless Steel (321) I pulled the
following prices from Burns Stainless site:
0.065 gage $30.10 1.34 lbs./ft
0.049 gage $22.64 1.02 lbs./ft
0.035 gage $20.55 0.73 lbs./ft
I don't have the weight for 0.035 gage Inconel 625 but it would probably
slightly more than SS of the same size. From what users have said, you
probably need 0.049 or 0.065 gage SS for exhaust stacks whereas you can
probably get by with 0.035 Inconel. The Inconel is about twice as expensive
(assuming we buy at $55/ft), lighter and more durable.
I assumed that 2" diameter tubing was the correct size but for the Mazda but
if I'm wrong we can get revised prices for 1-3/4". There might be an
additional price break at a high quantity and we might be able to get even
better prices if we went out for bid on the stuff. However, I like the
friendly arrangement that I have worked out with Shapiro (assembling
individual orders, billing and shipping individually for each member in the
group purchase).
Here is the route that I propose that we take:
1. Paul, before this note gets distributed would you make your
recommendations on the tube diameter/gage for the Inconel purchase.
2. All others that are interested please respond back with the quantity of
tubing (at the diameter/gage that Paul recommends) that you would be
interested in.
3. I will then get back with Shapiro for final pricing, payment methods,
expected delivery time.
4. I will then notify everyone via ACRE the final price quote and ask place
your order with Shapiro wants and arrange payment directly with them.
When I tried to get interest in a group purchase on Inconel bends I only got
4 or 5 responses. I think the problem is that a lot of people don't have
their exhaust design started and have no idea the bend size and quantity
needed. We might look for a company that would bend our tubing after we
have purchased the straight pieces on a piece by piece basis.
There is almost always some Inconel material being sold on E-bay. I picked
up some 1-1/2 tubing at about $6/foot. I also picked up some Inconel filler
rod. A friend of mine who is a master welder is practicing tig welding this
material. You might want to get some of the surplus Inconel and have your
welder (or yourself) do some sample welds before committing to the $55
material.
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