DECENT PROPOSAL?

What are your thoughts on the following proposal:

Spray System

Current Process:

Substrates = HRP&O, grit blasted HRS, shot peened HRS
Pretreat - Alkaline Clean, Rinse, Iron Phos, Rinse, Rinse (non-chrome sealer is used on the grit blasted substrate to reduce flash rusting)

Proposed Process:

Substrates = HRP&O, grit blasted HRS, shot peened HRS
Pretreat - Ambient Water Rinse, Iron Phos, Rinse, Rinse (no sealer)

We aim for 720 NSS hours at a failure of 7 (ASTM 1654) single scribe. We meet this with the current Process but want to reduce costs. This new process was proposed by a competing pretreat supplier not the current pretreat supplier.

Can we expect to have the same performance? What about cleaning?

Looking forward to your comments.

Hi Chris,

The competing supplier is probably pulling your leg if he's trying to convince you that a cleaner/phosphate with no sealing rinse will perform on an equal basis with your current process, which is an ideal set-up for a five-stage line. A cleaner/phosphate can be adequate for substrates which are not heavily soiled. HRPO does not normally fall into this category.

The only way to know for sure, however, is to do a side-by-side comparison between your current process and the new process. The new process may be cheaper in $/gallon, but can you put a price tag on the decrease in quality of your finished parts?