18 · Washer family on print
Flat washer vs lock washer on RFQ drawings
On stone cladding brackets, structural splices, and heavy baseplate joints, a size-only “washer” line without family forces dual quotes. Flat/plain washers spread bearing load; split/helical lock washers (弹垫) add spring resistance. Overseas buyers often say 平垫 / 弹垫 — this desk locks which family the controlling revision owns before any unit price is useful. Dashitou does not publish vibration guarantees, “universal washer” rules, or list prices here.
Define · what this RFQ is for
Use this desk when overseas buyers quote Dashitou stone · structural · heavy fasteners and the print must choose flat washer vs lock washer (plain bearing vs split/helical spring) for under-head or under-nut stacks. You own joint design and engineer sign-off; we confirm which washer family appears on the revision, OD/ID/thickness, material / finish lock, and qty band against that revision.
Pair with structural bolt class & coating (G8) when class/finish sit with the washer callout, stone-on-steel isolation when pads/isolation stack with washers, flange bolts vs hex head when under-head style is open, cladding bracket slot vs hole (G5) when hole type changes bearing, and drawing handoff for revision lock. Then open Enquire / RFQ.
Discuss · fields that change the quote
Each row below is a desk check. Missing rows stay Open — we do not invent washer OD tables, “弹垫 OK anywhere” rules, or vibration warranties on this public page.
Field desk · 01–06
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Washer family (flat vs lock) Name flat/plain washer (平垫) vs split/helical lock washer (弹垫). Size-only “M12 washer” invites dual quotes. Prefer the print’s named family or mark Open with a preference rule.
- Email example: Flat washer under hex head · OD/ID per ISO 7089 (Rev C)
- If missing: Open — do not assume spring washer from a stock photo
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OD / ID / thickness Clearance holes, counterbores, and cladding brackets care about OD and thickness. Write the note when the revision owns it; otherwise mark Open with a preference.
- Email example: OD 24 · ID 13 · t 2.5 · under nut
- If Open: mark preference on the print or RFQ notes
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Position & stack Under head, under nut, or both. Stone-on-steel isolation pads are not the same as washers — keep both lines when pads appear. See stone-on-steel.
- Email example: Flat washer under head; isolation pad buyer-named · dest EU
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Locking scope boundary Split washers are not nylon-insert or prevailing-torque lock nuts. If the print owns a lock-nut family, keep that desk separate — see nylon vs prevailing-torque.
- Email example: Split washer under nut · no nylon lock nut on this node (Rev C)
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Qty band & destination Mock-up joint set vs project lot; destination for packing notes. Discussion band is enough for the first reply.
- Email example: Qty band: mock-up 120 pcs → project lot TBD · dest EU
What must appear on the print
- Washer family named (flat/plain · 平垫 vs split/helical · 弹垫)
- OD / ID / thickness or standard when clearance owns the choice
- Position under head / under nut / both
- Grade / finish lock with the mating bolt — see A2 vs A4 coastal · structural class
- Controlling revision — see drawing handoff
Agree · before we number
Until the following are aligned, treat any figure as discussion only:
- Controlling revision locks flat vs lock washer (or marks Open with a preference)
- No invented “any spring washer” or site vibration tables posted as policy here
- Class/coating (G8), stone-on-steel isolation, and flange vs hex notes settled or linked in the same thread when those desks apply
- Samples and private-label marking only after washer family, size, and position are clear
We do not invent certificates, plant area, or ranking badges here. Project documents that matter to the RFQ are shared privately when relevant.
FAQ · flat vs lock washer
Is “washer M10” or “spring washer OK” enough on a stone/structural BOM?
Usually no. Flat/plain washers and split/helical lock washers are different geometry conditions. Name the washer family on the controlling revision, or mark Open with a preference rule. Vague washer-only language often forces a resubmit.
When should an RFQ lock a flat washer instead of a lock washer?
When the print needs bearing area and surface protection without a spring lock feature, and OD/ID/thickness (or a named standard) are frozen. Do not swap a split washer for flat on this public desk without the print. Write position under head/nut beside the callout.
Does choosing a lock washer replace naming a lock nut or isolation pad?
No. A split/helical lock washer is a washer-family geometry choice. Nylon-insert or prevailing-torque lock nuts, and stone-on-steel isolation pads, remain separate lines — see those desks when stack-up is still open. Treat them independently on the RFQ and the print.
Can one RFQ mix flat-washer and lock-washer zones?
Yes, when zones are explicit on the BOM (for example flat washers on cladding brackets, split washers on vibrating plant bases). Ambiguous “flat/spring OK” without zone ownership often splits the quote. Lock zones or mark Open with a preference rule.
What should I send so Dashitou can review the washer-family line cleanly?
Open Enquire / RFQ, then email the PDF/STEP or marked sketch to shizhanhao6@gmail.com in one thread. Include flat vs lock washer (split/helical), OD/ID/thickness or standard, position, material if relevant, A2/A4 or class/finish if relevant, qty band, and destination. Skim G8, stone-on-steel, and flange vs hex when those desks apply. No cart; no list prices on this site.
Next step
Skim structural bolt RFQ · stone-on-steel RFQ · flange vs hex RFQ · RFQ checklist, then open Enquire / RFQ. Direct email: shizhanhao6@gmail.com.