Run out of caustic soda and a cleaning cycle, a water treatment line or a production batch stops. Hold too much and you tie up cash and risk the product absorbing moisture in storage. A simple stock plan avoids both problems. Here is how to work it out.
Step 1: Know your usage
Look at the last three to six months of consumption and work out the average daily use in kg. Note any peaks, such as shutdown cleaning, seasonal production or boil-outs, which need extra stock.
Step 2: Know your lead time
The lead time is the number of days from placing an order to having the product on site. Include internal approval time, not just delivery. A supplier with ready stock and next-day delivery shortens this a lot.
Step 3: Add a safety stock
Safety stock covers unexpected demand or delays. A practical starting point is a few extra days of average use, more if your usage is irregular or supply has been unreliable.
Step 4: Set the reorder point
Reorder point = average daily use × lead time in days + safety stock
Example: a plant uses 75 kg a day (three bags). Lead time including approval is 3 days. Safety stock is 4 days of use, 300 kg. Reorder point = 75 × 3 + 300 = 525 kg, about 21 bags. When stock falls to 21 bags, place the next order.
Step 5: Choose the order size
Larger orders often get a lower price per kg, but only order what you can store properly and use while it is in good condition. Many buyers order by the pallet (40 bags, one tonne) because handling is easier and the rate per kg is better.
Storage keeps your stock usable
- Store bags sealed, on pallets, in a dry and covered area.
- Use the oldest stock first.
- Reseal opened bags immediately; caustic absorbs moisture and carbon dioxide from the air.
- Keep caustic away from acids and from aluminium or zinc.
Checking supplier stock
Your plan also depends on your supplier having stock when you need it. A supplier close to your site with ready stock shortens your lead time, so you can hold less. In the UAE, DUBI CHEM keeps caustic soda flakes 99% as ready stock in Al Hayl, Fujairah and publishes the daily caustic soda price online, with delivery across the UAE.