Bolt making machines

Screw production in a single step – precise, efficient, and up to 2,000 mm in length. Using cold or hot forming.

Our screw making machines combine all manufacturing steps in a single unit: from cutting the wire, pre- and final heading, pointing, thread rolling and milling, to the organized stacking of the finished parts. The length of the screws is limited only by the deflection of the wire.

With its exceptional in-house manufacturing capabilities, AMBA stands for quality, innovation, and maximum flexibility in meeting customer specific requirements.

The multi-talent among screw making machines

3 times faster

Over 300 pcs/min – three times faster than conventional machines on the market thanks to consistent cold forming.

The principle

All-in-one: All process steps in a single machine – no handling, no intermediate storage.

Up to 2,000 mm

The only manufacturer worldwide of all-in-one machines for screws over 2 meters in length.

Up to 11 process steps

Modular design with integrated cutting, heading, pointing, thread rolling, milling, and more.

Cold forming instead of machining

In cold forming, materials such as steel or stainless steel are plastically deformed without removing material and without prior heating. This allows a finished screw to be produced from wire in a continuous process without chip formation, without material loss, and with high strength.

“The throughput in cold forming is significantly higher than in machining, because the parts no longer have to be fed, clamped, and ejected individually. This turns a discontinuous production process into an almost continuous one, with enormous gains in productivity.”

Principles & Innovations

Rotary straightening unit

In-house developed straightening unit with an oscillating straightening vane. It is gentle and precise for perfect threads.

Servo wire feed

Servo motor controlled feed ensures ±0.15 mm tolerance without re-cutting and without material loss.

Horizontal spindle transport

Flexible transport of parts with or without a head to all stations, pan heads of up to 25 mm.

Hot & cold forming

Inductive heating up to 1,000 °C also enables the production of M24 bolts and square head screws.

An overview of our solutions

Screw blanks

All production steps, from cutting and heading to the discharge of the headed blanks. For screws 80–750 mm in length, up to 350 pcs/min.

All-in-one machines combine wire feeding from the coil, straightening and cutting, upsetting the head and rolling the thread in a single system and in one continuous process. Amba has now introduced a machine with wire diameters of up to 18 mm / 0.71 inches that integrates inductive heating.

Screws

Unique worldwide: screw production in a single step for lengths of over 2,000 mm. Modular concept with spindle transport system.

The rolled wire is fed from the coil via a drawing unit to the target diameter, pre-straightened in a rotating wire straightening system, cut to length and placed in the transport system.

The screw head is formed in two stages: first a preform volume is created, then the finished square head is produced. The upsetting heads operate with forces of up to 100 tons.

Leistungsstarke Maschinenlösungen für industrielle Fertigungsprozesse für Schrauben, Speichen, Rohrumformung. AMBA Produkte. AMBA Maschinen fertigen Produkte in einem kontinuierlichen Prozess her.

Hot forming and bi-metal solutions

Inductive heating up to 1,000 °C. Bolts with square heads and threaded bolts up to M24, lengths 200–1,000 mm. Up to 100 bi-metal screws per minute.

 Since very high forces are required when forming large-volume heads, Amba is transitioning from cold to hot forming for the first time and integrating a system for inductive heating.

 

Straightening machine RIM

Straightening hardened screws with full or partial thread up to 1,000 mm in length. Up to 40 pcs/min with a trough conveyor belt.

Will be coming soon

Machine, processes & result

11 Steps – One machine

01

Wire uncoiling & straightening

Driven wire decoiler with speed control and rotating straightening unit for perfectly straightened wire.

02

Cutting

Precise cutting with length tolerances of ±0.15 mm, without re-cutting and without material loss, for wire diameters up to 18 mm.

03

Pre-heading

Pre-heading and cold forming of the screw head, punching of hexagon heads in two steps, also pan-shaped, cylinder-shaped, and other special heads.

04

Final heading & reducing

Final heading with spring loaded tools. Reducing lengths up to 100 mm and more.

05

Rotating unit

Headed parts are rotated 180 degrees for further processing steps.

06

Reducing

Reducing lengths up to 100 mm and more.

07

Pointing

Tip pinching with up to 100 t pressing force in solid steel.

08

Thread rolling

Thread rolling with roll dies up to TR 7 (width up to 220 mm).

09

Placement in transport spindle

Automatic, sorted placement of finished screws, ready for packing or further processing.

10

Milling

Optional: milling as an inline process.

11

Robot stacking unit

Automatic placing finished screws into containers.

Detailed Specifications

Wire diameter

up to 20 mm

Shaft length

up to 2,000 mm

Output

up to 350 pcs/min

Accuracy

±0.05 mm

Drive

mechanically coupled

Control

PLC with HMI touch panel

Materials

steel, stainless steel, titanium

Surface finish

Ra < 0.8 µm

Tool change

< 20 min

Frequently Asked Questions

What is the working principle of a screw making machine?

The machine combines various processing steps into a single system – from the blank to forming the screw head and rolling the thread. Precisely coordinated, modular tools ensure controlled forming of the wire with significantly reduced unit costs and consistent quality.

What advantages does the machine offer in production?

The system replaces several individual machines, reduces space requirements, lowers logistics effort, and increases output and process reliability. Thanks to the shared drive of all stations, energy efficiency is also significantly improved.

What dies are used for thread forming?

Flat dies are used for thread rolling. Depending on the type, rolling dies up to TR8 and thread lengths of up to 600 mm are possible. In combination with the horizontal transport concept, significantly higher production volumes are achieved.

What is cold forming and why is it superior?

In cold forming, materials are plastically deformed without material removal and without heating. Throughput is significantly higher than in machining because parts do not need to be individually fed, clamped, and ejected. It is a nearly continuous process.

Interested in our screw making machines?

Whether standard or special screws, each machine is individually tailored to your products. Contact us for a personal consultation.