Introduction

Cold Forging is a cold working process where the material is squeezed into a die and the finished parts assume the shape of the die. This process is also known as Cold Heading. Bar stock or wire stock is fed into a die and is squeezed into the closed die. The resultant part is a nail, a bolt or a screw with the head. A subsequent cold heading operation forms other features on the head such as knurls or slots for screw drivers etc. This process can be highly automated and parts can be made economically. This method is used for both standard and special fasteners.
Cold Forged Range from M1.6 & limits to M27 & Length from 3mm upto 200mm.

Product Range

Hex Bolts, Heavy Hex Bolts, Eye Bolts, Machine Bolts, Allen Bolts, Hex Screws, Socket head Cap Screws, Jack Screws, Grub Screws, Socket Screws, Set Screws, Dowell Pins, Hex Nuts, Heavy Hex Nuts, Special Fasteners, Machined Components, Forged Rings & Special Fastening Components which are out of Cold Forged Range.
Common Cold Forged Products : Half threaded Hex Bolts, Allen Bolts, Machine Bolts, Full Threaded Hex Screws, Socket Cap Screws, Grub Screws, Set Screws, Hex Nuts, Heavy Hex Nuts, Nylock Nuts, Thin Jam Nuts, Thin Lock Nuts etc

Material Range

High Tensile, Structural Steel, Weathering Steel, High Temperature Alloys, Low temperature Alloys, High Carbon/Low Carbon, Marine Grade Alloys, Stainless Steel, Duplex Steel Alloys, Super Duplex Steel Alloys, Copper Alloys, Aluminum & Aluminum Alloys, ASTM Standard Materials, ASME Coded Fastener Material etc

Common Cold Forged Fastener Material: ASTM / ASME Standard A/SA 193, 194, 307, 320, F568, F593, F594, EN 3506 etc

Abstract

The use of finite element method increasingly as tool in metal forming industry result in cost reduction, time saving and improvement in product quality. The simulation software in the cold forging industry show material flow, capture the defects and allow to determine the
process parameters such as pres forces, die stresses, predict the tool life and fracture and calculate residual stresses. The present study reports two case studies of the cold forging in fastener production.

Advantages

Cold forged bolts and setscrews. M6 to M24, length 5mm to 250mm long

  • No heating required
  • Better surface finish
  • Superior dimensional control
  • Better reproducibility and interchangeability
  • Directional properties can be imparted into the metal
  • Contamination problems are minimized

Bolts

Cold forged bolts and setscrews. M6 to M24, length 5mm to 250mm long

Cold forging screws, M3 to M8 in carbon and stainless steel, up to 300mm long

  • Grades 4.6 to 14.9, W quality, SAE 2, 5, 8
  • Particular expertise with engine, suspension and wheel bolts
  • Range of heads including Hexagon, Flange Hexagon, Countersunk, Button, Tee, 12-point, Torx
  • Range of ends including Chamfered, Dog, CA, Paint Clearing Points
  • Captive washer assemblies (Sems), Paint clearing threads (Stets)
  • Thread forms including metric, coarse, fine and extra fine, Duo-Taptite, Corflex, Powerlok

Scews

  • Grades 4.6 to 12.9. Case hardened
  • Expertise in vehicle trims parts. Self tapping, thread forming
  • Various head forms and drive features including Hexagon, Flange Hexagon, Pan
  • Countersunk, Flange Pan with Torx®, Pozi, Supa Driv or Phillips drives and security drives
  • Various thread forms including Taptite II, Duo-Taptite, Taptite 2000, Hi-Grip, Plasgrip
  • Captive washer assemblies (Sems), Paint clearing threads (Stets)

Studs

Cold forged bolts and setscrews. M6 to M24, length 5mm to 250mm long

Cold forging screws, M3 to M8 in carbon and stainless steel, up to 300mm long

  • Grades 4.6 to 12.9. Case hardened
  • Expertise in vehicle trims parts. Self tapping, thread forming
  • Various head forms and drive features including Hexagon, Flange Hexagon, Pan
  • Countersunk, Flange Pan with Torx®, Pozi, Supa Driv or Phillips drives and security drives
  • Various thread forms including Taptite II, Duo-Taptite, Taptite 2000, Hi-Grip, Plasgrip
  • Captive washer assemblies (Sems), Paint clearing threads (Stets)

Materials for Cold Forming

The best material for cold forming a part may not be the same material you would use to machine it. The cold-forming company or your material supplier can work with you to determine the correct alloy for your part when it is cold formed. “Material flow and ductility are very key issues,” said Hughes. Knowledge of the behavior of materials can make the difference between a successful transition to cold forming and a frustrating experiment. Your cold-forming house will advise you, and you should be open to their recommendations. Any sulfur content in the metal would be detrimental to the heading process, for example. The qualities sulfur gives to a free-machining alloy make the material more likely to fracture during the cold forming process. So a material such as Type 303 free-machining stainless would not work. However, 302 HQ (heading quality) would be ideal. The material should be as soft as possible, ordered annealed at finish.

Die and Punch

Modern cold-forming machines, also called headers or parts formers, provide from one to seven die stations, opposite a number of punches mounted on a slide, which usually moves horizontally. A common type used for making bolts or screws is the one-die, two-blow header, similar to the example shown. This has one die, which is the diameter of the shank of the bolt or screw being formed. The material in the die is struck with two different punches, one after the other.

Closed Die Cold Forming

Our innovative cold forming methods, including 3-D modeling, enable us to quickly and precisely fabricate the tools necessary for your orders – with customized stocking and on-time delivery options. Our unique secondary operations have also allowed us to provide our customers with substantial cost savings on converted screw machine parts, stampings, die castings, powdered metal parts, forgings, and assemblies.

Secondary operations include:

Milling, Broaching, Knurling, Grinding, Drilling, Tapping, Shaving,Threading, Grooving,Burnishing, Slotting,Plating, Heat treating, Patching