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3‑way · diverts between two outletsL‑port 3‑way ball valve, SS316, 1/4" to 2"
A three‑way ball valve with an L‑drilled ball, which connects two ports at a time — so it diverts flow from one outlet to the other, or shuts off. SS316, 1000 PSI, 1/4" to 2", threaded BSPP or NPT. One valve where you would otherwise need two plus a tee.
What a L‑port three‑way ball valve is
Same body as the T‑port. Different hole through the ball.
A three‑way ball valve has three threaded ports instead of two, and a ball drilled so that turning the handle changes which ports are connected to which. It replaces a pair of two‑way valves and a tee with a single body and a single quarter‑turn action.
The letter describes the shape of the passage drilled through the ball. An L‑port ball diverts flow from one outlet to the other. That is the functional difference between this valve and the T‑port, and it is the only difference — the two share the same body, the same face‑to‑face dimensions and the same weights, right across the range.
- ⚠ It stops at 2". The three‑way pair runs 1/4" to 2" (DN8–DN50), where the two‑piece and one‑piece go to 4". Above 2" a three‑way function has to be built from two‑way valves.
- Reduced bore, as is normal for a three‑way. At 1/2" the bore is 10 mm. Getting a full passage through a ball in two directions is not geometrically possible at the same diameter — if flow area through the diverter is critical, use two full‑bore two‑way valves instead.
- The part number is where L and T differ. This range is VL‑S‑BL‑ against the T‑port’s prefix. Since the valves are dimensionally identical, the part number is the only thing on paper that tells them apart — worth double‑checking on an order.
- ⚠ Confirm the handle positions for your valve before you pipe it up. How the handle angle maps to which ports are open varies with how the ball and stem are keyed. We will confirm the port marking and handle mapping for the specific part rather than guess — get this wrong and the valve is plumbed backwards.
- Bonnet‑style body. Unlike the two‑way valves, the three‑way has a bonnet rather than a screwed‑in cap — see the bill of materials.
Four angles on the same valve. All photographs of the stocked item, not renders.
Specification
Everything that goes on a purchase order.
| Size range | 1/4" to 2" (DN8 to DN50) |
| Ports | Three, with an L‑drilled ball — diverts flow from one outlet to the other |
| Bore | Reduced bore, as is normal for a three‑way ball |
| Body material | Stainless steel SS316, with CF8M where the part is cast |
| Working pressure | 1000 PSI cold — derate for temperature |
| Working temperature | −29 °C to 150 °C |
| Connection type | Threaded BSPP or NPT |
| Seat and seals | PTFE seat, gasket, thrust gasket |
| Ball and stem | SS316, in an SS304 gland |
| Operation | Quarter turn manual lever |
| Part number prefix | VL‑S‑BL‑ — the only thing that distinguishes it from the T‑port on paper |
| Stock | Held in Malaysia or Singapore |
Bill of materials and sectional drawing
All 11 parts and what each is made of.
| No | Part name | Material |
|---|---|---|
| 1 | Bonnet | SS316 and CF8M |
| 2 | Seat | PTFE |
| 3 | Gasket | PTFE |
| 4 | Body | SS316 and CF8M |
| 5 | Ball | SS316 |
| 6 | Thrust Gasket | PTFE |
| 7 | Stem | SS316 |
| 8 | Gland | SS304 |
| 9 | Handle | SS201 |
| 10 | Washer | SS304 |
| 11 | Nut | SS304 |
The manufacturer’s sectional drawing. The callout numbers correspond to the part numbers in the table above.
- Everything wetted is SS316 or PTFE. Bonnet, body, ball and stem in SS316 (with CF8M where cast); seat, gasket and thrust gasket in PTFE.
- The thrust gasket is specific to the three‑way. A ball with three openings is less evenly supported than a two‑way ball, and the PTFE thrust gasket takes the axial load. It does not appear in the two‑way parts lists.
- Bonnet, not cap. The two‑way valves on this range have a screwed cap; this one has a bonnet. Same idea, different assembly, and it is why the numbering differs from the two‑piece.
- No anti‑static device listed. The one, two and three‑piece two‑way valves list an SS304 anti‑static device; this list does not. If you are on hydrocarbon duty and need the ball bonded to the body, tell us and we will confirm with the factory before you order.
- The PTFE seat sets the temperature ceiling, not the stainless — hence 150 °C. The derating curve.
Sizes, dimensions and part numbers
8 sizes. BSPP and NPT share every dimension.
Dimensions in millimetres. d is the bore through the ball, L the face‑to‑face length, H the overall height including the stem, and T the distance to the third port centre — which is the dimension you need when laying out the branch.
| Size | Bore d | Length L | Height H | Port centre T | Weight (kg) | Part no, BSPP | Part no, NPT |
|---|---|---|---|---|---|---|---|
| 1/4" | 6 | 65.5 | 100 | 51 | 0.58 | VL-S-BL-G-1000-04 | VL-S-BL-N-1000-04 |
| 3/8" | 6 | 65.5 | 100 | 51 | 0.55 | VL-S-BL-G-1000-06 | VL-S-BL-N-1000-06 |
| 1/2" | 10 | 75.5 | 100 | 57 | 0.52 | VL-S-BL-G-1000-08 | VL-S-BL-N-1000-08 |
| 3/4" | 15 | 82.5 | 108 | 62 | 0.71 | VL-S-BL-G-1000-12 | VL-S-BL-N-1000-12 |
| 1" | 20 | 88 | 140 | 72 | 0.98 | VL-S-BL-G-1000-16 | VL-S-BL-N-1000-16 |
| 1 1/4" | 25 | 105 | 152 | 88 | 2.18 | VL-S-BL-G-1000-20 | VL-S-BL-N-1000-20 |
| 1 1/2" | 32 | 135 | 166 | 100 | 3.17 | VL-S-BL-G-1000-24 | VL-S-BL-N-1000-24 |
| 2" | 39 | 149 | 170 | 102 | 4.38 | VL-S-BL-G-1000-32 | VL-S-BL-N-1000-32 |
- BSPP and NPT are dimensionally identical across the whole range — verified row by row. Only the part number changes. They are not interchangeable with each other.
- ⚠ These dimensions are identical to the T‑port valve. Same bore, same length, same height, same port centre, same weight, at every one of the 8 sizes. Only the part number prefix and the drilling differ — so you can substitute one for the other without touching the pipework, and you can also order the wrong one without noticing. Check the prefix.
- The 3/8" row shares the 1/4" body. Same 65.5 mm length, same 100 mm height, and the weight is actually marginally lower — 0.55 against 0.58 kg. Both sizes are machined from the same casting.
- The bore is well under the line size. 10 mm at 1/2", 20 mm at 1", 39 mm at 2" — expect a pressure drop and size on flow rather than on the thread.
- Weight climbs sharply above 1". 2" is 4.38 kg against 0.98 kg at 1", so support the valve rather than hanging it on the pipework.
Not sure this is the right one?
The choice between L and T is about how many ports you need open at once.
Choose the L‑port when
- You need to send one flow to either of two destinations, one at a time, or shut it off — classic duty/standby or tank selection.
- You want one valve and one action instead of two valves and a tee.
- The line is 2" or smaller.
- A reduced bore is acceptable — the duty is selection, not maximum flow.
Choose something else when
- You need to feed both outlets together, or mix → T‑port, which can connect all three.
- You are simply isolating one line → two‑piece (full bore) or one‑piece.
- The line is bigger than 2" → build it from two‑way valves and a tee.
- Flow area through the branch is critical → two full‑bore two‑piece valves.
- Service must happen without a line shutdown → three‑piece, though only as a two‑way.
- Water or air at modest pressure → brass, at 300 PSI, two‑way only.
All eight, side by side: the comparison table. Other variants: 1‑piece · 2‑piece · 3‑piece · T‑port · Brass · Brass mini · SS316 mini.
Questions we get asked
The ones that come up on the phone.
What is a L port ball valve?
A three‑way ball valve with an L‑shaped passage drilled through the ball. It has three ports instead of two, and the handle selects which are connected. An L‑port diverts flow from one outlet to the other. It replaces two two‑way valves and a tee with one body and one quarter‑turn action.
What is the difference between an L-port and a T-port ball valve?
Only how the ball is drilled — and therefore what the valve can do. An L‑port connects two ports at a time, so it diverts flow from one outlet to the other or shuts off. A T‑port can connect all three at once, so it will mix, split or divert. Mechanically they are the same valve: identical bodies, identical dimensions, identical weights at every size. Side by side.
Can I swap an L-port for a T-port without changing the pipework?
Yes. Every published dimension is identical — bore, face‑to‑face length, height, port centre distance and weight, at all sizes from 1/4" to 2". So the two are physically interchangeable in the same pipe. The flip side is that you can order the wrong one and not see it until it is fitted, so check the part number prefix: this range is VL‑S‑BL‑.
What size three-way ball valves do you stock?
1/4" to 2" (DN8 to DN50), in both BSPP and NPT. Note this is narrower than the two‑way range, which runs to 4" — above 2" a three‑way function has to be built from two‑way valves and a tee. Held in Malaysia or Singapore.
Is a three-way ball valve full bore?
No — reduced bore, and that is normal for the type rather than a compromise on this particular valve. You cannot drill a full‑size passage through a ball in two directions at once. At 1/2" the bore is 10 mm, at 1" it is 20 mm, and at 2" it is 39 mm. If flow area through the diverter is critical, use two full‑bore two‑piece valves instead.
Which handle position opens which ports?
Ask us to confirm it for the specific part. The mapping from handle angle to open ports depends on how the ball is keyed to the stem, and it is not something to assume from a general diagram — a three‑way plumbed on the wrong assumption sends flow to the wrong place. We will confirm the port marking and handle mapping before you order.
What pressure and temperature will it take?
1000 PSI and −29 °C to 150 °C. The PSI is a cold rating — the manufacturer’s curve is flat to about 20 °C then falls to roughly 67% of it at 150 °C, because the limiting part is the PTFE seat rather than the stainless body. The derating table.
What are the internal parts made of?
SS316 bonnet, body, ball and stem (CF8M where cast); PTFE seat, gasket and thrust gasket; SS304 gland, washer and nut; SS201 handle. The PTFE thrust gasket is specific to the three‑way — it carries the axial load on a ball with three openings. Full list on this page. Note this list does not include an anti‑static device; ask us if you need one.
Catalogue
Direct PDF download — no form, no email address.
Related: T‑port three‑way · all ball valves · class 150 threaded fittings for the branch pipework · all low pressure valves.
Tell us what has to connect to what
We will confirm whether you need L‑port or T‑port, verify the handle‑to‑port mapping for the specific part, and quote a landed price. Stock in Malaysia and Singapore.