Cylinder rental billing, drafted per customer from the tickets you already kept.

A driver leaves full cylinders, picks up empties, and the ticket records both, by gas, size and often cylinder number. At month's end someone rolls those tickets into a balance for each customer, applies the rental days, monthly holding charge or lease on every cylinder still out, sets apart anything the customer owns, and issues the bill. When a customer's purchasing office counts its own racks and gets a different number, that same person goes back through the tickets.

In the test, AI reads copies of those tickets, your rental schedule, lease agreements and last month's closing balance, then drafts each customer's rental bill: opening balance, cylinders out and back, closing balance by gas and size, days or holding charged, leases applied, and every cylinder or balance it could not tie out, with the reason. Nothing is posted anywhere, and your reviewer sets each draft beside the bill that went out.

The terms differ by customer, and sometimes by cylinder. The federal government's standard clause for returnable cylinders, FAR 52.247-66, lends them free for a set number of days after delivery, then charges a daily rental per cylinder by type, size, capacity and delivery point, ending once that rental reaches the replacement value. A lost cylinder costs its replacement value less the rental already paid on it. One welding supplier's published loan agreement charges a monthly rate on each cylinder still out after 30 days, for as long as it stays out. One state agency's 2026 solicitation asked instead for a five-year lease on every welding gas cylinder with refills included. Each draft names the agreement or schedule it applied, customer by customer.

When the clock stops is a clause, not a ticket date. Hawaii's 2023-24 state laboratory gas specification starts its lease charges on the day of delivery and stops them the day after the vendor receives its pickup notice, no matter when the truck actually comes, and puts any cylinder beyond the leases it bought on daily demurrage. One university's gas services page says monthly demurrage keeps billing until a cylinder is transportable, which takes a cap. Another runs its demurrage period from the 25th to the 24th of the next month. The draft shows which date it counted from and which rule moved it.

A cylinder can be counted three ways. The stamped serial number sits with the DOT specification marking under 49 CFR 178.35. A barcode sticker or tag is another identity, and the ticket's plain count by gas and size a third. One university's supply chain office tells departments to match the barcode on each cylinder against their monthly report and warns that rent keeps running until the inventory is adjusted. Another says that when the barcoded tag comes off a Size E oxygen cylinder it can no longer be tracked, and the department keeps paying for it indefinitely. The draft follows whichever identifier your tickets actually carry and marks any line it could match only by count.

Disputes end in a physical count. Hawaii's specification settles any disagreement over the cylinder balance with an audit by both parties before the next billing cycle, and requires cylinder ID numbers on delivery slips, pickup slips and rental invoices. A customer-owned cylinder should not be on the rent line at all, and one the customer says never arrived needs the signed ticket behind it. So the draft keeps every line tied to its ticket, lists each balance it cannot reconcile, and leaves the answer to your reviewer.

Rent and demurrage can be taxed differently. State decisions have gone different ways on whether a per-day charge for cylinders kept past a free period is taxable. A Virginia ruling treats demurrage as a service charge on a taxable lease, and a 2016 Georgia ruling lets cylinder rentals share the gas's manufacturing exemption when a completed certificate is on file. The draft decides none of that. It keeps rent, demurrage, lease and tax on separate lines for your reviewer, and nothing here is tax advice.

Once your reviewer says yes against the success criteria, the next rental runs get the same drafts for about 30 days.

A person on your billing desk checks every bill before it is entered anywhere or reaches a customer, and your cylinder records stay where they are today.

Anything after that is its own decision with its own price.