The Secret Behind The Precision Chronometer Of The Rolex Speed ​​regulation Mechanism

How does Rolex handle quality and precision? Let us look at two facts: first, the Rolex watch was assembled before the Super Observatory precision timepiece test. Its average daily error is -2 / + 2 seconds, which is more than twice as accurate as the average observatory-certified precision timepieces. From July 1, 2015, all Rolex watches are backed by a five-year warranty, setting a new benchmark for the watchmaking industry … So how does the brand achieve such accuracy and reliability? ? Part of the answer lies in the governing mechanism.

Rolex 4130 self-winding mechanical chronograph movement

   Of course, the results are not accidental. Rolex has a unique method of manufacturing watches and movements, also known as the ‘Rolex Way’. The main components required for its watches are produced by the brand itself. In general, specific technology solutions are continuously applied throughout the entire process. Proven solutions will be used as the new standard. Therefore, even though it is usually hidden under the case back, the Rolex movement is still visible at a glance. We can identify the Rolex movement by looking at the speed regulating mechanism, because the Rolex speed regulating mechanism has a distinctive signature feature.

Rolex Blue Parachrom Hairspring

   The speed governing mechanism is the core of the movement’s power and the most important part of the watch. The speed control mechanism includes an escapement and an oscillator, which defines the speed of the watch, also known as ‘time guard’. As a result, Rolex has also developed patented solutions in this area. Listed below are some of the most typical and prominent Rolex movement characteristics, all related to the core of power-speed regulation mechanism.

Cardless balance wheel with fine adjustment screws

Balance wheel with four gold trim screws

   There are two main ways to adjust the mechanical movement. The most common way is to use an adjuster to determine the effective length and speed of the hairspring by sliding the pins of the hairspring.

   Another solution is to use a cardless balance. The length of the hairspring is constant, and the watchmaker can move the screws or weights on the balance wheel to change the balance inertia, instead of making an argument on the length of the hairspring. The card-free balance is considered an advanced solution, which improves precision performance by avoiding certain risks. In addition, the card-free balance has better impact resistance, and the impact may cause the regulator to move.

   This is also the solution adopted by Rolex. Highly precision-balanced balance wheel (improved stability), equipped with two (four) gold fine adjustment screws for precise adjustment. For example, adjusting the screws inward (in pairs) will reduce the balance inertia and increase the speed, and vice versa.

Homemade blue Parachrom hairspring


The blue Parachrom hairspring and balance wheel parts have a pivot diameter of only 0.07 mm, which is equivalent to the diameter of a human hair.

   The internal parts of the watch can be magnetized. For a long time, watchmakers have tried to counteract the magnetic field with the help of a soft iron inner shell. However, this solution is ineffective for high-intensity magnetic fields and increases the thickness and weight of the case.

   Recently, research has focused on the movement itself, and more specifically the selection of the strategic components of the balance. In this regard, Rolex is one of the few brands that produces its own hairsprings and is one of the few manufacturers that can utilize paramagnetic / antimagnetic materials.

   Rolex developed the patented ‘Blue Parachrom hairspring’ and introduced it to the 4130 movement (Cosmograph Daytona watch) in 2000. The unique niobium-zirconium alloy has diamagnetic properties and can remain stable under temperature changes. In 2005, Rolex also adopted a new patented technology to improve the surface of Parachrom hairsprings and further improve their long-term stability. In 2014, Rolex also introduced a silicon hairspring in the 2236 movement (for the assembly of ladies’ watches). Of course, Rolex’s antimagnetic achievements do not stop at the hairspring level. For example, the balance wheel pivot is also specially designed to optimize the antimagnetic performance.

Rolex end spring

Rolex Blue Parachrom Hairspring

   The shape and attachment of the hairspring determine how it expands and contracts. Most watches use flat spiral hairsprings, but hairsprings have other shapes. Breguet bends the outer end of the hairspring and places it near the pivot of the balance wheel. This allows the hairspring to ‘breathe’ symmetrically and evenly, effectively improving isochronism. Rolex used the Breguet end curve manufacturing process and optimized it, naming it the Rolex end circle spring.

Straddle balance wheel bridge

A new generation 3255 mechanical movement with 14 patented technologies introduced at Baselworld 2015

   Traditionally, the balance wheel is fixed under the splint with one end fixed. In modern Rolex movements, the balance wheel bridge plate adopts a straddle design, and the two ends are fixed, so that the oscillator is stably and accurately positioned. The rigidity of the bridge plate also greatly improves the impact resistance of the balance wheel.

Rolex Paraflex cushioning

Rolex Paraflex cushioning

   The pivots and jewel bearings of the balance wheel (sometimes other key components) are particularly fragile and are prone to damage after impact. With the help of the shock absorbing device, the gem is mounted on the spring, leaving a buffer space to absorb the impact. The Swiss watchmaking industry has two main shock protection systems-Incabloc and KIF. Some manufacturers use their own systems. For years, Rolex has favored the KIF anti-vibration system. In 2005, the brand developed and patented an exclusive cushioning device called Paraflex. Paraflex cushioning has a unique geometry that is instantly recognizable. Rolex claims that this innovative spring geometry improves the efficiency of the shock absorber by 50%, while retaining the precision timepiece performance of the balance wheel.

4 Hz standard frequency

   Theoretically, the higher the frequency of the movement, the more accurate it is (of course, the rate must be stable first). However, there are some disadvantages to increasing the frequency band of the movement-for example, more friction or less power reserve. Almost all modern Rolex movements have a vibration frequency of 28,800 times per hour (4 Hz), which the brand believes is the best compromise between high precision adjustment and reliability. In the 1990s, Rolex equipped the Daytona watch with an improved ElPrimero movement, but lowered the vibration frequency from 5 Hz to 4 Hz.

Chronergy escapement

Rolex Chronergy escapement

   The Chronergy escapement was used for the first time in the 3255 movement (2015 Day of the Week 40 watch). It is an optimized version of Rolex’s Swiss lever escapement. The goal of Rolex engineers is to increase the dynamic efficiency of the escapement while retaining its reliable performance. The ratio of the length between the escapement gear tooth and the escapement fork gem is exactly the opposite. The escapement gemstone is now only half as thick as before, and the contact surface of the escapement gear mouth is doubled. The components of the escapement are no longer aligned, but are slightly offset to increase leverage. The escapement fork and escape wheel are manufactured with high precision using LIGA technology. The escapement wheel has a notch design to reduce inertia. In addition, the parts are made of nickel-phosphorus and are not affected by magnetic fields. Rolex claims that the efficiency of the escapement has been increased by 15%, which has also halved the power reserve of the 3255 movement.

Lubrication-Epilamage coating

   It is said that the watchmaker Mr. Arabhan-Louis Breguet once said, ‘Give me the perfect oil, and I will give you the perfect watch.’ Rolex does not often promote technological progress, but the brand’s official website has released some interesting news : ‘Rolex has developed a new type of exclusive lubricating oil, which is synthesized independently. Over time, its service life and stability have been significantly improved.’ The brand is silent on the development progress, so we know so much at present, but the lubrication work And Epilamage coating is really essential for Rolex. (Photo / text watch home compiled by Xu Chaoyang)