DIN 103 Metric Trapezoidal Screw Threads — Limiting Dimensions, 7e External / 7H Internal (TR8 – TR40)

Documents

Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.

Quotation

• The fastener family (DIN 103 Metric Trapezoidal Screw Threads — Limiting Dimensions, 7e External / 7H Internal (TR8 – TR40)) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
• Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
• Quantity per size and your target delivery date.
• Destination country, and any required documents (for example a mill test certificate) so the quote includes them.

Sample & supply

Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.

Storage & shipping

Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.

How do I pick the pitch on a trapezoidal thread, and what does the 7e/7H class pair actually control?

Pitch on a trapezoidal thread is a motion-vs-strength trade, and the designation makes it explicit: TR20 is available at x2, x3 and x4 in the collected chart — the x2 gives finer positioning per turn and a stronger flank for the same major diameter (more thread depth relative to lead), while the x4 moves the nut twice as far per revolution but leaves less metal in the flank. Lead screws and positioning duty lean fine; hand-operated presses and jacks lean coarse because operator turns are cheap and flank load is not. Above TR22 the ladder widens further (3/5/8 at TR22, 3/6/10 at TR30–TR40), so large screws can move fast without extreme helix angles. The class pair answers a different question: how much clearance the running pair has. 7e (external) puts the screw's limiting diameters entirely below basic and 7H (internal) entirely above, so the assembled pair always has running clearance — a manufactured-in guarantee that a lathe-cut screw and a tapped nut will turn without binding. That clearance is also why trapezoidal threads carry play under reversal load; where a mechanism cannot tolerate it, anti-backlash nut designs or tighter classes are the fix, and both are RFQ conversations, not chart lookups. Order the pair together — screw class, nut class and pitch as one line — and the collected tables on this page give the gaging limits both faces must meet.

What is the MOQ and lead time for threaded parts on this standard?

The minimum order quantity is 10,000 pieces. Stock items ship in 3–7 days; non-stock items are confirmed at quotation. Common thread sizes on this standard are widely stocked; confirm the exact schedule against quantity and size mix at quotation.