Valves, threads & fittings
Five connections, two gasket materials and the $6 part that decides whether a container lives another three years.
- Sheet
- 80
- Revision
- 2026-10
- Scale
- 1:1
- Drawn at
- Peoria IL
The five connections you will meet
| Connection | Where | Nominal | Mates with | Notes |
|---|---|---|---|---|
| S60x6 buttress | Outlet on most composite totes | 2 in / 60 mm | Hose, camlock, NPT adapters | Coarse buttress — fine variants exist, measure |
| 2" NPT | Plumbed lines, steel IBCs | 2 in | Everything industrial | Tapered; needs tape or dope |
| 6" buttress | Top fill opening | 6 in / 150 mm | Vented and solid caps | Not interchangeable with 9 in |
| 9" screw lid | Older and open-top units | 9 in | Dedicated lids only | Harder to source; we stock some |
| Tri-clamp | Sanitary stainless | 1.5–3 in | DIN, NPT via adapters | Gasket choice matters for CIP |
- Standard outlet valve
- 2" butterfly, polypropylene body, EPDM seat
- Upgrade valve
- 2" full-port ball valve — better throttling, fewer weeps
- Gasket standard
- EPDM: water, caustic, ag chemistry, most industrial
- Gasket upgrade
- Viton: solvents, fuels, aromatics, high temperature
- Vented cap threshold
- Any product that off-gasses — hypochlorite above all
- Tamper ring
- Polypropylene, single use, expected by most fillers
Gasket material by chemistry
| Product | EPDM | Viton | Our pick |
|---|---|---|---|
| Water, brine, de-icer | Excellent | Good | EPDM |
| Caustic soda | Excellent | Fair | EPDM |
| Sulphuric acid (dilute) | Good | Excellent | EPDM, Viton if hot |
| Sodium hypochlorite | Good | Good | EPDM + vented cap |
| Mineral oil, diesel | Poor | Excellent | Viton |
| Aromatic solvents | Poor | Excellent | Viton + steel container |
| Vegetable oil | Fair | Excellent | Viton |
| Glycol | Excellent | Good | EPDM |
- A weeping outlet is a gasket or a grit problem nine times out of ten. Try the $6 seal kit before the $24 valve.
- A caved-in bottle means the vent was shut during discharge. Fit a vented cap and the problem disappears forever.
- Never mix thread standards with adapters stacked two deep. Each junction is a leak waiting for a Friday afternoon.
Four valve types, and when each is the right one
| Valve | Flow (water) | Throttling | Grit tolerance | Price | Best for |
|---|---|---|---|---|---|
| 2" butterfly, polypropylene | 25–40 gpm | Poor | Poor | $14–22 | The standard; fine for clean liquids |
| 2" full-port ball | 30–45 gpm | Good | Good | $24–34 | Anything you meter or throttle |
| 2" ball with cam handle | 30–45 gpm | Good | Good | $28–40 | Frequent cycling, gloved hands |
| 3" butterfly (large outlet) | 60–90 gpm | Poor | Fair | $34–52 | Viscous product, fast discharge |
- A butterfly valve seals by squeezing a disc into an elastomer seat. One piece of grit on that seat is a weep, which is why 24% of our intake fails on the valve and why a $6 seal kit fixes most of it.
- A ball valve has a wiping action that tolerates grit far better. If your product carries any solids at all, the $10 upgrade pays for itself the first time.
- Never throttle with a butterfly for long periods. Partially open, the disc sits in the flow and the seat wears unevenly, which is a weep three months later.
- If you dose or meter, use a ball valve and put the metering device downstream, not the valve itself.
Sealing, torque and the adapter chains to avoid
- S60x6 outlet to valve
- Hand-tight plus a quarter turn on the gasket. No tools, no sealant
- NPT connections
- PTFE tape or paste, 2–3 turns past hand-tight. Tapered thread seals on the thread
- Buttress cap
- Hand-tight onto the gasket. Over-torquing deforms the seal and causes a vacuum collapse
- Bulkhead fittings
- Gasket both sides, tightened against the wall, never with the nut cutting into the bottle
- Tri-clamp
- Finger-tight on the wing nut; the gasket does the work, not the clamp force
- Gasket reuse
- Never on a food-grade release. Rarely anywhere else — they are a few dollars
- Never stack more than one adapter. Every junction is a leak waiting for a Friday afternoon, and a chain of three is how a transfer ends up on the floor.
- Never mix thread standards in a chain without a proper transition fitting. Buttress into NPT by force destroys both.
- Never use PTFE tape on a buttress thread. It seals on the gasket face, not the thread, and tape in the gasket groove causes the leak you were trying to prevent.
- Never discharge with the top cap sealed. The container pulls a vacuum on itself and the top caves in — we take in six or seven of these a year and every one was avoidable.
- Never use a metal adapter on a plastic outlet without supporting its weight. A heavy camlock on an unsupported thread cracks the outlet collar.
My valve weeps. Valve or seal kit?
Seal kit first, nine times out of ten. Open the valve, look at the seat ring: a broken or pitted witness line means grit, and a $6 kit fixes it. Replace the whole valve only if the body is cracked or the stem is loose.
How do I know whether my outlet is S60x6 coarse or fine?
Measure the pitch across five threads, or simply bring the valve to a supplier. Fine-pitch variants exist and they will start to thread onto a coarse fitting before binding, which is how threads get destroyed.
Can I fit a sight gauge?
Yes — a bulkhead pair top and bottom with clear tube between them. It is our second most common retrofit after hose adapters, and it is the only reliable way to read the level on a stained or wrapped container.
Do I need a vented cap?
If the product off-gasses at all — hypochlorite above everything — yes, and it is not optional. Also fit one if you ever discharge quickly, because the vent is what stops the container collapsing.
What gasket for a product that changes?
Viton. It costs more and covers a far wider chemistry range. If a container is dedicated to one product forever, EPDM is cheaper and usually better for water, caustic and ag chemistry.
Can I re-use the tamper ring?
No. It is a single-use indicator and re-using one defeats the only thing it does. They are about two dollars.