News and Reports from Our Company

Plants:

Hannover Messe 1995: The main topic of the conjoint booth of Schramm Coatings GmbH and Boockmann GmbH was the presentation of a completely enclosed impregnation plant with inside manipulators, and post combustion and energy recovery integrated in the process.

Freely programmable manipulators decouple the process steps, so that several batches of ballasts and small transformers of 1 to 30 kg of weight taking different hardening times can be processed in one oven at the same time.

1993: Issue of European Patent no. 0374649B1 „Method and an apparatus for impregnating or coating object“.

Main claim:
„The method according to the invention for impregnating and/or coating objects in a drip-, and/or dipping roller installation by passing the objects through a preheating zone, at least one drip-, dipping roller- and or coating zone, an after baking zone, and possibly at least one intermediate baking zone is characterised in that the outgoing air from the drip-, dipping roller-, coating-, intermediate baking- and/or after baking zone is passed as crude gas to a post-combustion installation, wherein the crude gas is heated by indirect heat exchange with the clean post-combustion gas, that the clean post-combustion gas is returned at least partly to the preheating zone, and that the energy content of the clean gas which is returned to the preheating zone is adjusted in such a way that the energy requirement of the preheating zone is basically just met.“

1991: Paper „Energy saving and emission reducing impregnation technique“

In the issue 6/1991 of the German trade journal „farbe + lack“, the implementation of an economic, energy saving impregnation plant with a thermal post-burning unit is described and a performance balance is given. This article is available on request.

When electric coils (transformers, ballasts, motors) are impregnated with unsaturated polyester resins, styrene is emitted. In common impregnating plants, high air flow rates needed for waste air treatment cause high energy consumption. Using the EEC-technique, flow rates are reduced, controlled and re-circulated. This allows a self-preserving, energy saving thermal post-combustion, which adapts itself to the incurred emission. The surplus of energy set free when burning the used solvent is re-circulated into the process.

Helilub:

International trade fair „Draht und Kabel“ in Duesseldorf, April 8th to 12th, 2002:
The main topic of our booth was the introduction of computer-aided process data documentation for our lubricating system Helilub.

Many producers of magnet wire need to log process data continuously as to be able to provide evidence of their quality and quality assurance. Using our process data documentation system, all settings, events, parameters and values of Helicord devices NB52, NB53 and NB54 can be recorded and compiled in an inspection sheet, so that all determining factors and basic conditions can be displayed later on.
We use a similar system to be able to trace back every single spool of our lubricant yarn used for lubricating magnet and winding wire.

1999: Internal memo concerning the VOC directive 1999/13/EC and its effects on lubricating magnet wire

In annex IIA of the VOC directive 1999/13/EC, which is valid in all countries of the European Community, the legal emission of volatile organic compounds resulting from the production of winding wire is limited to 5, respectively 10 g per kg of wire, depending on the wire diameter. The transition period for refitting existing plants will end on Oct. 31st, 2007.
Our Helicord system using the Helilub technique for emission free lubrication of magnet wire complies with all requirements of this directive. Especially when it comes to high speed production plants (up to VxD = 200), the Helilub technique alone allows very accurately and constantly measured, emission-free lubrication.

International trade fair „Draht und Kabel“ in Duesseldorf, April 20th to 24th, 1998: The main focus was set on the introduction of Helilubricators for cold and fine wire.

Helilubricators for cold, fine and ultra-fine wires can be placed right before the take-up as well as be used for vertical wire run. Also, we introduced the budget-priced melt felt technique combined with an infrared pre-heater.

Electrical Insulation Conference Sep. 22nd to 25th, 1997: Presentation „Magnet Wire Lubrication“

In this paper, the Helilub technique for solvent-free lubrication of magnet wire is described in detail and compared to other techniques, including operating expenses. It shows that Helilub is technologically and economically superior to other techniques (e.g. using rollers or melt felt technique).
This article is available on request and can also be found on the pages 195 to 201 of the 1997 Proceedings of the conference.

1994: Issue of the European patent no. 0499775 „Verfahren und Vorrichtung zum Gleitfähigmachen eines Drahtes“ (Solvent-free lubrication of magnet wire)

Helilub technique uses a tension and speed controlled string - which has previously been impregnated with a melting, solvent-free lubricant - wrapped around a wire. It gives a multiple 360° contact under controlled friction with constantly renewed string, and guarantees reliable surface preparation. Controlled friction and speed difference of string and wire as well as the precisely calibrated amount of lubricant on the string determine the amount of lubricant applied to the wire and permit prediction of parameters and calculation of results.
This technology has been approved for round wires of 0.012 to 5 mm in diameter.

1992: Essay „Emission-free Lubrication of Enameled Wire“ in issue 2/1991 of the German trade journal „Drahtwelt“

Résumé:

Winding wires have to be surface treated to provide good and easy processing in the following production steps. Up to now, solvents had to be used to dilute paraffin and other kinds of wax and apply them onto the wire. Now a technique has been discovered that allows melting said lubricants and polishing them onto the wire surface.

Helicord

2007: Internal memo concerning the application of PTFE-dispersion, e.g. Teflon® to insulated conductors.

Conventional release agents adhere very poorly or not at all to the surface of wires and insulated impregnated conductors. When conformal coating with resin, coils made of these conductors, usually a very strong adherence of the insulation to the resin occurs. If such a coil gets bent or twisted, the insulation may break, so that the coil becomes damaged or even useless.
This can easily be avoided by applying a PTFE-dispersion to the wire surface, using strong friction and an apt metering device. The water evaporates or is wiped away by the cord, the polymer is burnished onto the conductor surface, adhering to it very strongly. There will be no more adherence to the resin, and durability of coils will increase noticeably.

The coefficient of friction of aluminum wires could be improved from 0.35 to 0.11, the coefficient of cables with polyurethane insulation was enhanced from 0.5 to 0.3.

2006: Presentation at the „American Welding Society Show“ in Atlanta, GA, USA, on Oct. 30th to Nov. 11th, 2006

In this presentation, the principles of Helicord are described in detail with respect to the production process of welding wire. Besides, the application of PTFE-dispersions and the use of Helicord for abrasive and solvent aided cleaning of Al-wire, as well as for lubricating to enhance feedability are explained, some concrete examples are given.
The presentation is available on request.

Technical Report, August 2006:

Helicord has been adapted to be applicable also for high voltage conductors and stranded wire up to 12 mm of diameter.

Some improvements:

• extended and reinforced process zone
• steel frame for protection from mechanical impact
• vacuum device for extracting dust and particles, using a filtered circular air flow
• motor-driven looping unit for easier handling

With these improvements and using our new flat Helicords we achieved cleaning performance by far better than ultra sound or high pressure.

International trade fair „Draht und Kabel“ in Duesseldorf April 24th to 28th, 2006 New at this exhibition: flat Helicords for treating stranded and large-core wire

The flat Helicords have been developed to avoid convergence of loops, and to meet extremely high surface purity requirements, e. g. for welding wire, stranded wire and cables by giving a bigger contact area. They are also applicable for copper clad optical fibers.

The composition of Helicords can be customized to meet different needs.

Demonstration of multi-stage abrasive treatment:
wire cleaning, surface treatment, abrasive, oxide removal

Solid impurities on the wire surface, e. g. powdery drawing agents like calcium stearate or graphite, can easily be removed by abrasive treatment. It requires several Helicord models NB 55 and NB56 to be arranged in line.
The demonstration unit was set up of two NB55 devices, the first one using abrasive Helicord, the second one using an absorbing type of cord. Both devices were supplied with a fluid with low surface tension, so that formation of dust was minimized and the cleaning performance was maximized.

2006: Development of the Metering Pump NB40B886

The metering pump was developed to support the removal of soluble residuals of drawing agents off the wire surface, so that ultrasonic cleaning could be replaced. It is also apt for applying liquid lubricants and anti-corrosives on welding and other wires, as well as for metering cutting oils, e. g. when using high speed cutters.

The amount to meter can be frequency controlled (e. g. using a stroke or pitch rate sensor) or pulse width modulated.

2006: Patent Publication „Device and Method for cleaning a wire or the outer surface of a tube“ (Helicord)

Main claim:
“The invention relates to a device for cleaning a wire or the outer surface of a tube, both preferably with a rounded cross section, using textile or textile-like material strands which move substantially parallel to and against the direction of travel of the wire or tube, the textile or textile-like material strands, surrounding the wire or tube in the form of at least one loop lying close thereto in a looping zone and optionally containing cleaning material, wherein the approach and exit angles of said material strands are flat with respect to the wire or the outer surface of the tube. When a plurality of loops is present, it can be said to lie in a spiral manner….”

December 2005: Application engineering report „Cleaning and Lubrication of Welding Wire“

Non-metallic impurities affect the weldability and feedability of welding wires. For smooth welding of high-alloy welding wires, a dead surface without drawing residuals have been proven beneficial. To achieve this, the wire should be cleaned after drawing. Using our Helicord system, impurities can be reduced by up to 70 %.

By lubricating the wire, the coefficient of friction is reduced and feedability is enhanced. Wax-like lubricants and oils with additives, that also enhance weldability, seem to be most valuable. Contrary to trials with other lubricating systems which did not achieve any satisfactory performance, Helicord met or even exceeded the requirements of several manufacturers of welding wire.

June 2005: Application Engineering Reports:

Surface treatment of silver-plated wire:
Loose metal particles and drawing residuals on silver-plated wire, e. g. for medical applications, cause problems during following production steps. Using a Helicord device NB55 and a dry Helicord, we achieved a cleaning performance significantly better than ultrasonic cleaning.

Cleaning steering conductors:
For military use of single-wire steering conductors, a minimum length of faultlessly insulated wire is required. Using Helicord, these requirements can be met more reliably than before. The amount of substandard products was decreased significantly.

Cleaning of high frequency communication and coaxial cables:
Copper deposits in the extruder nozzle often cause insulation faults of high frequency communication and coaxial cables. Using Helicord, the required minimum length of faultless insulation was achieved and no blow-out occurred during 8 hrs. production time, which had not been accomplished by any other technology so far.

Application of anti-corrosive lubricants on steel wire:
Rust and oxidation may decrease the windability, particularly of non-alloy steel welding wire. When lubricated with anti-corrosives (e. g. wax), rust-resistance may rise up to 400 %. Thick layers don't absorb any dust, and the lubricant doesn't diffuse into the filling of cored wire.

Cleaning aluminum wire for the food industry:
After drawing, aluminum wire to be used by the food industry has to be cleansed of drawing residuals (mineral oil) and should be lubricated. Using Helicord, residuals were decreased to 1 mg/m² and a wax-based lubricant was applied.

The Helicord – system has been approved for these materials:

superconductors and

solid or cored wire made of

aluminum, copper, mild steel, spring steel, stainless steel, molybdenum, titanium, silver (also in different alloys or coatings).

We removed:

residuals of drawing agents or solvents, copper or other flakes and debris, mineral oil and oily impurities.

We applied:

wax, oils, PTFE, rubber-like release agents, solvents (e. g. white spirit or water) and anti-corrosives.