Plumbing & Pipe Flow Calc
Friction pressure loss in psi (and feet of head) over a pipe run by the Hazen-Williams formula, from flow, size and C factor.
OtherLiveeip155:8453Exactvia cdp
PlumbingPressure-dropHazen-williamsHead-loss
Calls · 30d
1
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far.
$24.31
Verified settled volume
1,175 settlements proven x402 by their on-chain EIP-3009 marker.
$0.020
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-10-20 20:30Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xb531320805C5BED1D46AEaDcF4F008FDF172DBDaThe wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
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"description": "Friction pressure loss in psi (and feet of head) over a pipe run by the Hazen-Williams formula, from flow, size and C factor.",
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"asOf": "2026-10-12T01:57:25.778Z",
"pipe": "3/4 in copper-l",
"source": "computed locally (Hazen-Williams: psi/ft = 4.52 Q^1.852 / (C^1.852 d^4.8655))",
"cFactor": 140,
"flowGpm": 10,
"reasons": [
"Hazen-Williams suits water at ordinary temperatures in pipes above 2 inches; it is a conventional estimate for smaller pipes.",
"Doubling the flow multiplies the loss by about 3.6."
],
"summary": "3/4 in copper-l at 10 gpm over 100 ft loses 11.07 psi (11.07 psi per 100 ft).",
"verdict": "COMPUTED",
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"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
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"Doubling the flow multiplies the loss by about 3.6."
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"verdict": "COMPUTED",
"degraded": false,
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
"lengthFeet": 100,
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"psiPerFoot": 0.11067,
"totalPsiLoss": 11.067,
"psiPer100Feet": 11.067,
"feetOfHeadLoss": 25.56,
"kilopascalsLoss": 76.3,
"lossIfFlowDoubled": 39.951,
"insideDiameterInches": 0.785
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"cFactor": 140,
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"reasons": [
"Hazen-Williams suits water at ordinary temperatures in pipes above 2 inches; it is a conventional estimate for smaller pipes.",
"Doubling the flow multiplies the loss by about 3.6."
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"verdict": "COMPUTED",
"degraded": false,
"disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
"lengthFeet": 100,
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"water temperature and very high or low velocities where the formula is less accurate",
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"psiPerFoot": 0.11067,
"totalPsiLoss": 11.067,
"psiPer100Feet": 11.067,
"feetOfHeadLoss": 25.56,
"kilopascalsLoss": 76.3,
"lossIfFlowDoubled": 39.951,
"insideDiameterInches": 0.785
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"llms": "https://plumbing-calc.x402tookit.com/llms.txt",
"catalog": "https://plumbing-calc.x402tookit.com/catalog",
"message": "Plumbing & Pipe Flow Calc has 8 pay-per-call endpoints (Pipe volume, flow velocity, Hazen-Williams pressure loss, pipe sizing by velocity, thermal expansion, drain slope, tank fill time and bucket flow tests.), from $0.02 a call. See the full menu and send your agents our way.",
"openapi": "https://plumbing-calc.x402tookit.com/openapi.json",
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"url": "https://plumbing-calc.x402tookit.com/tank-fill-time",
"path": "/tank-fill-time",
"what": "Time to fill or drain a tank from its volume or round tank size and flow in gpm, with an…",
"price": "$0.02"
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{
"url": "https://plumbing-calc.x402tookit.com/thermal-expansion",
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{
"url": "https://plumbing-calc.x402tookit.com/bucket-test",
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"what": "Flow rate in gpm and litres per minute from a bucket test: container volume and seconds t…",
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}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.02USDC≈ $0.02 USD
on Base · exact scheme
Pay 0.02 USDC on Base to 0xb531…2DBDa. The signed payment is good for 5 minutes.
- Paid to
- 0xb531…2DBDa
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 20000 smallest units
20000units
on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- DUPiup…eEm8s
- Token contract
- EPjFWd…TDt1v
- Payment window
- 5 minutes
20000units
on Polygon · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0xb531…2DBDa
- Token contract
- 0x3c49…c3359
- Payment window
- 5 minutes
20000units
on Arbitrum · exact scheme
That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.
- Paid to
- 0xb531…2DBDa
- Token contract
- 0xaf88…e5831
- Payment window
- 5 minutes
The catalog’s raw entry
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}
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"output": {
"type": "json",
"example": {
"asOf": "2026-10-12T01:57:25.778Z",
"pipe": "3/4 in copper-l",
"source": "computed locally (Hazen-Williams: psi/ft = 4.52 Q^1.852 / (C^1.852 d^4.8655))",
"cFactor": 140,
"flowGpm": 10,
"reasons": [
"Hazen-Williams suits water at ordinary temperatures in pipes above 2 inches; it is a conventional estimate for smaller pipes.",
"Doubling the flow multiplies the loss by about 3.6."
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"verdict": "COMPUTED",
"degraded": false,
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}Provenance
- Seen in the source catalog
- 2026-10-20 20:30Z
- Last indexed by Roundhouse
- 2026-10-22 12:40Z
- Last enriched (probe, favicon, geo)
- 2026-10-20 20:45Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 4 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service Plumbing & Pipe Flow Calc and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=Plumbing%20%26%20Pipe%20Flow%20Calc' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://plumbing-calc.x402tookit.com/pressure-loss, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.