Category 06 · Milk line and tank

Most valve leaks are a tired seat, not a bad valve.

Butterfly valves: per unit Check and sample valves: per unit Replacement seats: by valve size Freight and Wisconsin sales tax extra

Ask the cheap question first

Is it the valve, or the seat?

A sanitary butterfly valve is a stainless disc turning inside a rubber seat. The stainless doesn't wear out in any time frame that matters to you. The seat does. When a valve drips past closed, or the handle has gone stiff and then suddenly loose, nine times in ten a new seat puts it right for a fraction of a new body.

So tell us the size and, if you can read it, the make. We stock seats for the common 1.5, 2 and 3 inch bodies and will say plainly if yours is a pattern we can't match. What we won't do is sell you a whole valve to fix a seat problem.

The seat material is the real choice on this page. There's a table for it further down, and the short version is: EPDM for most milk and caustic wash, silicone where the line runs hot for long spells. The gaskets and seals page covers the same materials for tri-clamp joints.

Stainless butterfly valve with trigger handle on a milk line — Trigger handle, clamp ends. Turn it a quarter and it's open; the seat does the sealing.

Item 06.1

Sanitary butterfly valves

Quarter-turn shut-off valves with a 304 stainless disc and body, clamp ends, and a choice of EPDM or silicone seat. Handles come as trigger or pull type, sized from 1.5 to 4 inch.

The trigger handle locks at open and closed, and on some patterns at a few points between. It's the one we recommend on a milk line, because a pull handle can be knocked half-open by a passing shoulder or a swinging hose. Pull handles make sense where a valve is opened and shut dozens of times a day by the same person, like a vat outlet.

A butterfly valve is a shut-off, not a flow control. Run it half-open for long and the seat wears on one edge and the milk takes a beating through the gap. If you need to throttle, tell us what you're trying to do and we'll talk it through.

Price basis Per unit By size, seat material and handle type

Butterfly valve specification
Body and disc	304 stainless
Seat	EPDM or silicone
Handle	Trigger (locking) or pull
Ends	Tri-clamp; match the ferrule, see tri-clamp fittings
Sizes	1.5, 2, 3, 4 in
Spare seats	Stocked for common 1.5, 2 and 3 in bodies

Send a part inquiry

Hand drawing a milk sample from a stainless sample valve

Item 06.2

Check and sample valves

A spring check valve stops milk running back through the pump when it shuts off. A sample valve lets the hauler or the lab draw a clean sample from the tank without opening the lid.

The check goes on the pump discharge, and the direction arrow on the body matters more than anything else about it. Fit it backwards and the pump dead-heads against it. When a check valve chatters, it's usually oversized for the flow: the spring never gets pushed fully open, so the poppet bangs on and off its seat. Size it to the line, not one up.

Sample valves are small, and they get ignored until a hauler complains. The seal inside is a little elastomer plug that hardens after enough hot washes, and then the valve drips between samples and grows its own culture. They're cheap. Replace them on a schedule, not when the lab calls.

Price basis Per unit Check valves by line size; sample valves by mounting

Check and sample valve specification
Check valve type	Spring-loaded poppet, clamp ends
Check valve use	Pump discharge, to stop backflow on shut-off
Sample valve type	Small sample cock for tank testing
Material	304 stainless body, elastomer seals
We need	Line size and flow direction, or the tank mounting for a sample valve

Send a part inquiry

Choosing the seat material

Temperatures are working guides for continuous exposure. A few minutes above them during a wash won't ruin a seat; running there every day will shorten it.

EPDM against silicone for valve seats
Condition	EPDM	Silicone
Working temperature	up to about 300°F	up to about 400°F
Alkaline (caustic) wash	Good. The standard choice.	Fair. Softens over time in strong caustic.
Acid rinse	Good	Fair
Milk fat and oils	Swells in high-fat product and oils	Better, but not the answer for oils either
Steam	Good for short steam cycles	Good
Wear from cycling	Tough, holds shape	Softer, tears more easily if run half-open
Where we'd fit it	Raw milk lines, pump discharge, most parlours	Hot product lines, pasteuriser outlets, long hot holds

Running cream, butter or anything oil-based through the valve? Tell the desk. Neither seat here is ideal, and we'd rather ask than send one that swells shut in a fortnight.

Valve inquiry to delivery

Size, type, seat
Tell us the clamp size, whether it's butterfly, check or sample, and which seat you want. A photo of an old valve with its handle helps.
Seat or whole valve?
If a seat will fix it, the desk says so and prices both. You choose.
Written price and lead time
Stock, the indicative price and when it leaves. Nothing is charged until you confirm.
Packed and shipped
Seats and small valves confirmed by early afternoon usually go the same day. More on how ordering works.

Worth knowing first

Used seats
We don't sell pulled or used seats. Rubber that has been clamped has already taken its set.
Automated valves
No air-actuated or controlled valve packages. This counter is for manual valves and their wear parts.
Seats we can't match
If your body is an odd pattern and we can't confirm the seat by size and photo, we'll tell you rather than send something close.

Valve inquiry

Size and seat, and we'll do the rest.

A photo of the old valve, handle and all, speeds things up. Send it to [email protected] or ring the desk on (608) 355-8791.

Name *

Phone *

Email *

What you need

Delivery address or town and ZIP *

Spec

Just a seat? Say so and give the body size.

Notes

Foremost Farms may contact me about this inquiry. I have read the privacy policy and the terms.

Inquiry only. The desk replies with stock, an indicative price and a lead time. Nothing is charged online.