Phillips and Jones - Quality Surgical Instruments

Processes in manufacturing

Most of the surgical instruments go through 28 or more steps before they are hand-inspected, packaged and shipped to our customers. Phillips & Jones has several fully mechanized units capable of producing large volume of instruments. Following is a brief introduction to some of the major steps in manufacturing our instruments:

1) Forging / Stamping
This is the first and one of the most crucial steps in the production of surgical instruments. First, pre-cut / fabricated lengths of Stainless Steel sheet or stock bars are heated in specialized furnaces. When they reach a specified temperature, they are inserted in forging presses where they are hammered in the shape, size, and geometry of the instrument to be produced. The mold/die used in hammer forging is made from high strength die-steel and is a critical component in maintaining tight tolerances in the final products. Once forged, Stainless Steel hardens as it is allowed to cool down quickly at ambient temperature.

2) Annealing
Forged pieces of Stainless Steel are next annealed in vacuum furnaces. These furnaces are typically batch-furnaces where batches of forged instruments are annealed under vacuum to prevent corrosion. Annealing is a process which makes Stainless Steel soft for machining. This is a slow process where forged pieces are heated to a pre-determined temperature and later allowed to cool down very slowly over a period of time. The cool down stage sometimes take more than 10 hours based on the type of material etc.

When annealed properly, the grain structure of Stainless Steel grows to a larger size which allows for easy machining and makes it ductile for forming, shaping, and sizing in the later stages.

3) Milling / Machining
Next the annealed products are machined and milled based on the requirements of the final design. Specialty high-speed cutters are used for introducing teeth, serrations, ratchets, box-joints, etc. Milling machines are equipped with pneumatic clamps which hold the products in place as they are being milled and machined.

4) Grinding / Sizing / Setting
Once the products are milled and machined, they are next grinded using high speed medium-coarse grinding wheels and belts. This process is used to remove any excess material left in the forging process and also to size the instruments as per the required tolerances.

Once raw shape of the instruments is defined by coarse grinding, highly skilled technicians take the adjoining pieces of instruments and set them together. At this stage, the final shape of the instrument immerges and is bound together using screws or rivets in case of forceps and scissors. The serrations, ratchets, and teeth are also aligned and straightened in this step to form the perfect fit.

This is one of the most important aspects of handcraftsmanship as it requires years of training before technicians are allowed to work independently.

5) Heat Treatment
Instruments when sized and set for perfect fit are next Heat Treated in highly sophisticated furnaces. Heat-Treatment furnaces can either be continuous (belt operated) or batch depending on the volume and size of the instruments. Typically this process is carried in an inert environment (Nitrogen or Argon gas filled) to avoid oxidation and corrosion of final product. This process is used to harden the annealed instruments as per the final requirements.

This is also an important step as the hardness of the instruments must be within a few degrees. Excessive hardening causes the instruments to break in operation and lower than permitted hardness prohibits proper operation / cutting of instruments.

After Annealing as well as Heat-Treatment, the instruments are tested using Diamond-Tipped Rockwell Hardness Test fixtures to ensure proper hardness at any given stage of the process.

6) Finishing / Polishing
Hardened instruments are next grinded (using fine and extra fine wheels and belts) to remove deep scratches from the medium-coarse grinding/sizing in the previous stages. This step is also used to size the product as per the requirements. Typical tolerances of ± 2 millimeters are achieved at this stage of processing.

Next the instruments are polished as per the final requirements either to a Satin finish (aka Matt / dull finish) or Mirror (shiny) finish.

7) Water / Chemical Testing
Once the instruments have been finished, they are next subjected to either Chemical or Boil tests depending on the type of instruments. These tests are conducted not just on a representative batch rather on all the instruments produced to insure superior quality. Just another example of how we do not comprise when it comes to quality!

8) Re-Finishing
After Chemical / Boil tests, all the instruments are examined for any unfinished surfaces. During this stage any instrument that does not pass the initial QC is sent back to an earlier step depending on the corrective action.

9) Decreasing / Cleaning
Once an instrument gets to this stage, it is primarily a finished product and is next subjected to deep cleansing and decreasing of oils and finishing materials in water or chemical based ultrasonic cleaning machines.

10) Final Inspection
After final cleaning / decreasing, instruments are thoroughly Hand-Examined and tested by a highly qualified team of QC inspectors. Each and every aspect of an instrument is examined including serrations, ratchets, jaws, and teeth.

11) Labeling / Packaging
All the instrument that are approved by the final inspection department are finally packaged and labeled as per the requirements of a customer and are ready to ship at that time.