Currently, we export more than one hundred varieties of machined parts and castings, and have a strong presence in the market.
We have the ability to develop the parts, quickly from the drawings CAD model to pattern or investment casting die to actual casting to machined part. We can do so within a span of 6-10 weeks depending upon the size and criticality of the part.
We can also offer all the parts made from bar stock (as per material specifications) as well as sheet metal parts.
We offer a comprehensive product range that covers the entire spectrum of sand casting, investment casting and other machined parts. These products go through a strict quality control system to make sure they are of optimum quality and offer superlative performance. Moreover, we are constantly in the process of expanding our product portfolio across markets and brands while keeping a strict eye on quality.
A : Podbielskistraße 251, 30655, Hannover
Investment casting according to the lost wax method is a very old casting process, having been used in ancient Egypt for the production of art and cult objects. Today this production method is gaining popularity. Through the use of high temperature resistant moulding material binders, this method has many advantages in comparison with other casting methods.
Vast variety of materials - All steel and stainless-steel materials as well as aluminum alloys, brass and bronze can be cast, very close to the final shape, by means of the highly refractory ceramic shell.
Design latitude- Creative design improves function, saves expenses and gives a sophisticated appearance to the final product. The investment casting method offers this liberty, because undercuts, thin wall-thickness or three-dimensionally shaped areas can be produced with this casting technology.
Close tolerances and high quality surfaces- In many cases parts can be manufactured ready for installation. This saves machining costs. Draft angles are usually not necessary.
Materials: | Steel, high-grade and stainless steel alloys according to DIN, EN, ISO, ASTM, BS, JCSI. Special materials based on Cobalt and Nickel, aluminium alloys. |
Weight per piece: | Steel, high-grade and stainless steel materials 0.005 to 50,00 kg. Aluminium alloys 0.005 to 20,00 kg. |
Dimensions: | Max. 500 x 500 x 500 mm. |
Tolerances: | According to VDG P690 (about ± 0,7 % of the nominal dimension). |
Quantities: | Small, medium, and large series. |
Machining equipment: | All current processing methods, CNC and conventional machining. |
Surface treatment: | Hot-dip galvanising, galvanising, Cr6 free coating, glass balls and shot blasting, priming, electro-polishing, tumbling, burnishing, pickling, passivating, lacquer finishing. |
Checking equipment: | Chemical analysis by spectrometer, mechanical properties for tensile strength, yield stress, notched bar impact testing, X-ray, pressure testing up to 200 bar, 3-D co-ordinate CNC measuring machine, metallography, magnetic particle flaw inspection. |
Approval: | TÜV, Det Norske Veritas (DNV), Lloyds Register Of Shipping, NKK (Nippon Kaiji Kyokoi). |
Quality System: | EN ISO 9001:2008 - ISO TS 16949. |
Special approval: | AD 2000 W0 / TRD 100. |
Casting your ideas: We will gladly consult and assist you in choosing the right process whether it be; sand casting, shell mould casting, centrifugal casting, precision casting, die-casting, or any other that is suitable for you.
Vast variety of materials Grey iron casting, ductile cast iron, steel casting, stainless steel casting (corrosion-, wear- and heat-resistant), case hardening steels and heat-treatable steel. Our delivery program includes aluminum as well as brass and bronze alloys.
Various completion optionsYou may want a raw cast part, because you have your own machining facilities. Alternatively, you prefer a part machined and ready for assembly, or already assembled as a component, lacquered and coated?
Materials: | Grey cast iron, nodular cast iron, malleable cast iron black and white, special and high quality steel, unalloyed and alloyed steel (stainless and corrosion-resistant, heat-resistant, wear-resistant) acc. to DIN, EN, ISO, ASTM, BS, JCSI. |
Weight per piece: | Depending on casting process 0,2 kg up to more than 1,000 kg. |
Dimensions: | Max. 2.450 x 2.000 x 1.450 mm. |
Quantities: | Medium and large seriea. |
Machining equipment: | All current processing methods, CNC and conventional machining. |
Surface treatment: | Hot-dip galvanising, galvanising, Cr6 free coating, glass balls and shot blasting, priming, electro-polishing, tumbling, burnishing, pickling, passivating, lacquer finishing, KTL coating. |
Quality control: | Chemical analysis by spectrometer, mechanical properties for tensile strength, yield stress, notched bar impact testing, pressure testing up to 200 bar, 3-D co-ordinate CNC measuring machine, metallography, magnetic particle flaw inspection. |
Approval: | TÃœV, Det Norske Veritas (DNV), Lloyds Register of Shipping, NKK (Nippon Kaiji Kyokoi), Germanischer Lloyd. |
Quality System: | EN ISO 9001:2008 - ISO TS 16949. |
Special approval: | AD 2000 W0 / TRD 100 and PED 97/23/EC Annex I, Par. 4.3. |
Die Casting is the process of forcing molten metal under high pressure into the cavities of steel molds, called dies. Dies range in complexity to produce any non-ferrous metal parts (that need not be as strong, hard or heat-resistant as steel) from sink faucets to engine blocks (including hardware, component parts of machinery, toy cars, etc).
In fact, the process lends itself to making any metal part that must be precise, must have a very smooth surface that can be bright plated without prior polishing and buffing, have very thin sections, must be produced much more economically, must be very flexible in design; a single die casting may have all the features of a complex assembly.
Materials: | Aluminium die-casting
Pressure die-casting Zn400 ZAMAK3, Zn410 ZAMAK5, Zn430 ZAMAK2. Further materials upon request. |
Weight per piece: | Aluminium: 0,01 to 10,00 kg Zinc: 0,01 to 2,00 kg. |
Quantities: | All current processing methods, CNC and conventional machining. |
Machining equipment: | All current processing methods, CNC and conventional machining. |
Surface treatment: | Powder coating, lacquer finishing. |
Checking equipment: | Chemical analysis by spectrometer, mechanical properties for tensile strength, yield stress, notched bar impact testing, X-ray, pressure testing up to 200 bar, 3-D co-ordinate CNC measuring machine, metallography, magnetic particle flaw inspection. |
Quality System: | EN/ISO 9001:2008 - ISO/TS 16949. |
This forming technology drop forges or presses the warm or cold raw material into two or more multi-part moulds (closed-dies).
When drop forging parts, the structure of the raw material remains intact thereby maintaining excellent mechanical properties. These forged parts have highly elastic properties, are ductile and have dynamic resiliance. Sudden shock overload applied to these parts does not lead to brittle breakage, but they absorb maximum tension by being a bit plastic.This attribute is achieved without any particular constructional effort.
The already existing very good mechanical properties can be supplemented and optimized by heat treatment. Parts produced using these methods are well suited for later machining.
By combining processing methods such as warm-cold forming or cold coining, dimensional accuracy can be reached which may make additional machining unnecessary.
Materials: | Steel and stainless steel according to DIN, EN, ISO, ASTM, BS, JCSI. |
Weight per piece: | 0,05 to 1.000 kg. |
Dimensions: | Depending on shape and weight. |
Quantities: | Medium and larger series. |
Machining equipment: | All current processing methods, CNC and conventional machining. |
Surface treatment: | Hot-dip galvanising, galvanising, Cr6 free coating, glass balls and shot blasting, priming, electro-polishing, Nickel plating, tumbling, burnishing, pickling, passivating, lacquer finishing. |
Quality control: | Chemical analysis by spectrometer, mechanical properties for tensile strength, yield stress, notched bar impact testing, ultrasonic testing, magnetic particle flaw inspection, liquid penetrant test, 3-D co-ordinate CNC measuring machine, metallography. |
Approval: | TÜV, Det Norske Veritas (DNV), Lloyds Register of Shipping, NKK (Nippon Kaiji Kyokoi). |
Quality System: | EN ISO 9001:2008 - ISO TS 16949. |
Special approval: | AD 2000 W0 / TRD 100 and PED 97/23/EC Annex I, Par. 4.3, ASME Sect. III Audit. |
Powder Metallurgy (PM), also called Metal Injection Moulding (MIM), allows sophisticated and near-net-shape products of high complexity without (in most cases) needing a further machining.
Metal powder of 5-20 µm grain size is formed together with a selective binder. Debinding followed by sintering under vacuum brings up gas-tight, scale free, resilient, and ready-to-use MIM form parts.
Precision tools and fully automated production processes help designers to exploit all degrees of freedom and create enormous rationalization potentials for both new and existing components.
Besides surface roughnesses of Ra 0,5 - 1,0 µm, food-safety according to LFGB DIN 10955 / DIN EN 5495, and a minimum of machining neccessity, this economical and ecological production method allows thin wallthicknesses and the most complex undercuts.
Step 1: Feedstock – Very fine metal powders are combined with thermoplastic and wax binders in a precise recipe. A proprietary compounding process creates a homogenous pelletized feedstock that can be injection molded just like plastic. This achieves ultra-high density and close tolerances over high-production runs.
Step 2: Molding – The feedstock is heated and injected into a mold cavity under high pressure, allowing for extremely complex shapes. Once the component is removed it is known as a "green part."
Step 3: Debinding – the “green part” is then put through a controlled process called debinding that removes the binder and prepares the part for the final step. Once the debinding is complete, the component is referred to as “brown.”
Step 4: Sintering – the “brown” part is held together by a small amount of binder and is still fragile. During sintering temperatures reach near the melting point of the material. Sintering eliminates the remaining binder and gives the part its final density and strength.
Materials: | Steel, magnetically soft steel, stainless steel, titanium, super alloys, carbide metal, heavy metal, copper alloys. |
Weight per piece: | 0,02 - 150 g. |
Dimensions: | max. length 150 mm, wall thickness 0,2-10 mm, max. volume ca. 20.000 mm3. |
Tolerances: | ± 0,3% - ± 0,5% from nominal dimension, angles ± 0° 30'. |
Quantities: | Medium and large series. |
Machining equipment: | Calibrating, turning, milling, drilling, grinding, honing. |
Surface treatment: | Thin-film-technology, electroplating, lacquer finishing, glass balls and shot blasting, tumbling, polishing, lapping. |
Quality control: | 3-D co-ordinate CNC measuring machine, CNC video checking machine, hardness and density control. |
Quality System: | EN/ISO 9001:2008 - ISO/TS 16949. |
Special approval: | AD 2000 W0 / TRD 100. |
Modern machining centres with auto-feeders allow a variety of different chipping methods thus granting almost endless constructional possibilities.
Prototypes, small but aklso large series can be economically produced - without even needing to invest into tools!
Precision, reproduction, and keeping the given tolerances are an important factor as well as high quality surfaces.
Almost any metallic material can be machined, using special cutting tools for materials with highest mechanical standards.
Materials: | Steel, stainless steel, aluminium, brass, special alloys. |
Weight per piece: | 1 g to 1.000 kg. |
Dimensions: | Ø 2 to Ø 800 mm. |
Tolerances: | According to DIN ISO 2768 or DIN 7168. |
Quantities: | Small, medium and large series. |
Surface treatment: | Hot-dip galvanising, galvanising, priming, electro-polishing, tumbling, passivating, lacquer finishing. |
Quality System: | EN/ISO 9001:2008 - ISO/TS 16949. |
Stamping is a metalworking process by which sheet metal strips are punched using a press tool which is loaded on a machine press or stamping press to form the sheet into a desired shape.
This could be a single stage operation where every stroke of the press produce the desired form on the sheet metal part. Or the stamping can be done in a series of stages in a press tool to perform various stamping operations to get the required form on component.
Materials: | Sheets made of aluminium, steel and stainless steel. |
Weight per piece: | 0,005 - 1,5 kg. |
Dimensions: | Max. 2.450 x 2.000 x 1.450 mm. |
Quantities: | Medium series: 10.000 to 100.000 pieces |
Machining equipment: | Milling, drilling, thread cutting, welding. |
Surface treatment: | Hot-dip galvanising, galvanising, priming, electro-polishing, tumbling, passivating, lacquer finishing. |
Quality control: | 3-D co-ordinate CNC measuring machine, hardness test, spectrometry. |
Quality System: | EN/ISO 9001:2008 - ISO/TS 16949. |
The Rajhans Corpation was approached by a customer who was looking to die-cast parts and then use the parts “as cast” with no additional machining, resulting in a piece that fit together tightly and would be leak free upon assembly. Thanks to our expertise in die-casting, our team determined that the parts, if designed according to intent, may have issues regarding casting tolerance and measurement in the future. Knowing that, our experts compiled a list of suggestions that you can find toward the end of this report.
In order to create the part as specified, a number of things that would need to be considered in order to guarantee success. Among them, the fact that the part would need to be overmolded in order to hold electrical connections in place. To inject the overmolding, our experts determined that the high tolerance areas within the piece would need to be sealed off, and that it would need to be done in a way that not only allowed the pieces to fit together, but also be measured, with precision.
In order to create the part as specified, our team identified a number of things that would need to be considered in order to guarantee success. Among them, the fact that the part would need to be overmolded in order to hold electrical connections in place. To inject the overmolding, our experts determined that the high tolerance areas within the piece would need to be sealed off, and that it would need to be done in a way that not only allowed the pieces to fit together, but also be measured, with precision.
After analyzing the challenges and collaborating with the client, our team reached a number of conclusions regarding the machining, tooling and overall production of the part. Firstly, it became clear that the sealing surfaces, as well as the mating parts where the surfaces join, will have to be machined to the specified tolerance. Secondly, our experts suggested that the part also be redesigned to allow for draft in the interior walls so that the part may be released from the die, and then have the draft be machined in order to bring the walls into tolerance for overmold tooling. Finally, as expected, issues arose when measuring the parts due to set-up of the parts and datum. To solve the problem, our team measured with the CMM and verified the dimensions through 3D scanning.
The following report is an analysis of the hole position tolerance for a handlebar weldment. We have further studied our manufacturing and inspection practices, and have determined that 100% of our parts meet the drawing requirements. We understand that there is an issue fitting the handlebars to the mating “pod” assembly, so you will find our suggestion near the end of this report.
The pods don’t have dimensions corresponding to 492.4 and 547.6 mm. As drawn, the four tapped holes are not controlled as a pattern. As such, the tolerance for their locations is unknown. The pod – handlebar assembly uses countersunk head screws, which serve an aligning function. This restricts any relative motion between the parts when as screws are tightened, and takes up some of the fit tolerance. An M4 screw has a max OD of 4 mm. The nominal hole size in the base is only 4.5 mm. This allows for .5mm of misalignment between the pod holes and handlebar base holes. As each screw is tightened, the allowance is becomes even smaller for the remaining holes. This clearance is not sufficient to ensure all of the parts assemble together.
Tightening the hole position requirements on the handlebar will make manufacturing more difficult, and will add to cost. As it is, about 10% of the production parts would have to be reworked or scrapped in order to ensure each part will fit the test gauge. It would be more cost effective to ensure the parts fit by enlarging the hole size in the handlebar bases.
We suggest that the customer determines the value of T2 by capability study of the pods or some other means. The client can then calculate the required size for the handlebar base holes, and give this number to the The Federal Group.
How To Meet The Print Without Breaking The Bank. A case study in optical measurement innovation using automotive flanges manufactured by Rajhans Corpration
You have a small manufacturing business. But, you still need accurate dimensions for your production part qualification process. You can’t afford a full-blown metrology department with a giant CMM. There is an innovative solution using machine vision to measure your parts. A high-resolution off-the-shelf scanner can be combined with a free optical measurement analysis program to get you the accuracy you need. You can now enjoy this new part measurement capability. It’s a new complement to our suite of measurement devices now available for you.
Pictured Right / Above: The high-resolution scanner we used for this case study.
Optical measurement is a fast, economical way to measure features on planar surfaces.
Here are some ways that you can benefit from optical measurement software:
The inspection process demands accurate measurements. Every measurement system has its strengths and weaknesses.
The strength of this measurement methodology is that it provides capabilities that aren’t easily achievable with other available tools. The distance between hole centers is often a critical fitment criteria. Getting accurate manual measurements is tedious.
By establishing points on the arc of the circle, you can calculate the center point. The benefit of this methodology is that you can easily determine center-to-center distance conformance to the fitment criteria after you calculate the center points of two or more holes.
Pictured Right / Above: Calibration stick in blue. This is a measurement of a product. In red is the calculated distance between the center points of two holes—a tough measurement to get manually.
This measurement methodology gives you high resolution — less than +/- 0.001” linear and less than 0.5° angular. The scanner resolution is critical for measurement accuracy.
The system is limited to the evaluation of planar / flat surfaces that will fit on the scanner bed (roughly 8.5″ x 11″ for our current setup). When used skillfully, it can give you an accurate visual record of the part analysis (see below).
Measurement systems that are not fully autonomous are susceptible to user variation (i.e., the user must accurately place the software’s visual markers on part characteristics).
Our operators are trained to produce accurate and repeatable measurement results for you.