Bolt Forming Machines from Yeswin: Types, Process, Selection
A bolt forming machine, or bolt former, is a multi-station cold forming machine that turns cut wire into bolt blanks by upsetting, extruding, piercing and trimming it in a row of dies. YESWIN builds 3, 4 and 5 station models for M3 to M30, plus long stroke versions for bolts up to 400 mm.
This guide is the starting point. It explains what the machine does, then points you to four deeper articles: how to choose a model, how the process works station by station, how flange bolts are made, and how long bolts are made. Read the section that matches your decision.
Last updated: 2026-11-11
Table of contents
What is a bolt forming machine?
It is a machine that shapes metal wire into bolt blanks at room temperature, using several dies in sequence.
Wire is fed, cut to a set volume and passed from die to die by a transfer mechanism. Each station does one job, so no single blow asks too much of the metal. The process is cold forming, and it work hardens the part: in a laboratory study of five-stage forming, average hardness rose from 158.6 HV to 207.6 HV, about 31 percent (Yang and Liu, MDPI Applied Sciences, 2023). For a broader view of the technology, see what is a cold forming machine.
The need is steady. Taiwan's fastener exports reached 327,100 tons in the first quarter of 2025, up 3.37 percent year on year (Fastener World, 2025). The question for most buyers is not whether to form bolts but which machine fits their parts.
How do you choose a bolt former?
Work backwards from the part: head shape, diameter and length decide the stations and the stroke.
The right machine is rarely the one with the most stations. Three stations suit simple head shapes, four suit moderately complex parts, and five suit complex geometry such as automotive bolts, banjo bolts and stepped shafts. Diameter runs from M3 to M30, and length decides whether you need a standard or a long stroke model.
Read the full guide: how to choose a bolt former. It covers the five checks, the feature options worth paying for, and what to send for a quote. The models are on the 3-station, 4-station and 5-station pages.
How does the bolt forming process work?
The wire is cut, then upset, extruded, pierced and trimmed across the stations, with a transfer mechanism moving the blank between dies.
The cut matters first: in the same laboratory study, the cut-off ends measured 173 and 194 HV against 142 HV in the middle of the billet, and their flow lines were bent (Yang and Liu, 2023). Later stations do the real shaping, and the second stage alone reduced the cross-section by 43.9 percent.
Read the full guide: bolt forming process, station by station. It follows one blank through the machine and explains why several blows protect the part.
How are flange bolts manufactured?
By upsetting wire into a head with an integral flange, usually over three to five stations, while keeping the grain flow continuous at the head-to-shank fillet.
In a published test of a DIN 6921 M8×60 class 10.9 flange bolt, four ways of starting the head gave four different results, and only one produced a fully compatible grain flow (Dubiel, Balawender and Osetek, Archives of Metallurgy and Materials, 2021). Standard flange bolt dimensions are set by standards such as ISO 15071, which covers sizes M5 to M16.
Read the full guide: flange bolt manufacturing. It covers the standards, the model choice and the first-off checks.
How are long bolts manufactured?
On long stroke bolt formers, which extend part length up to 400 mm while keeping the M3 to M30 range.
Long parts include anchor bolts, elevator bolts, concrete screws, timber screws, roofing screws and connecting rods. Length selects the long stroke line, and the part shape then selects 3, 4 or 5 stations. Anchors and studs usually follow ASTM F1554 or ISO 898-1, so name the standard when you ask for a quote.
Read the full guide: long bolt manufacturing. It includes the part table and a length checklist for buyers. The range itself is on the long stroke bolt former page.
Frequently asked questions
What does a bolt forming machine make?
It makes bolt blanks, including hex head bolts, cap screws, flange bolts, weld bolts, anchor bolts, elevator bolts and many special parts. Threading and heat treatment usually follow on other equipment.
What size range do YESWIN bolt forming machines cover?
Standard and long stroke bolt formers cover M3 to M30. Parts formers for special shapes cover M6 to M30. Long stroke models reach lengths up to 400 mm.
How many stations do I need?
As few as the part allows. Three stations suit simple heads, four suit moderate complexity, and five suit complex shapes. The selection guide explains how to decide.
Does the machine decide the bolt's strength class?
No. The machine forms the shape. The property class under ISO 898-1 depends on material and heat treatment.
How do I get a quote?
Send the part drawing, size, material, volume and any options you want. You can use the contact page or download the catalog first.
Ready to match a machine to your part?
Send us the drawing and your volume, and we will recommend a model.