A point lock for turnouts is a safety-relevant device on turnouts that ensures that the switch blade makes contact with the stock rail at the same time, thus preventing misalignment or slipping. The point lock is indispensable, especially for points with sharp points (when driving over the point to exit into the left or right branch). It secures the switch against unintentional movement and prevents the train from being endangered if it is cut open (i.e. if it is driven around in the wrong position). The mechanical catch reliably holds the correct position in the end position. It also reacts to changes caused by thermal expansion or vibration and compensates for them – technical details that guarantee safe operation.
Function & structure: How a point closure switch works
The classic lace fastener usually consists of a clip fastener, more rarely hook or hinge fasteners. When changing the points:
- the outlying tongue is first moved and guided to the cheek piece,
- then the adjacent tongue is indented,
- Finally, the locking mechanism engages and fixes the position.
A precisely designed connecting rod or slide rod together with the switch lever ensures that the switch and stock rail remain firmly connected.
The tip lock prevents the tongue from sliding under the influence of wheel load or temperature movement,
which could otherwise lead to damage. In addition, a missing end position of a switch blade immediately signals a fault in the signal box via the switch blade tester or switch signal.
Why is the toe closure essential?
Without a functioning point lock, every turnout is at risk, especially when traveling over a point. Sources of error:
- A single point lock is no longer sufficient for switches with long tongues → additional center locks required
- When driving up (cutting open), the switch can remain in the wrong position without a lock
- When the temperature changes, the tongue moves when the closure gives way mechanically
Switches without the correct locking mechanism can thus become a source of train departure problems and track damage.
Point locking points & point machine: coordination for safe end position
Whether mechanically localized or electrically remote-controlled, the point machine must work precisely with the point lock. After reaching the end position, the switch lever still has an adjustment travel to engage the lock. This is the only way to ensure the correct position „i.e. complete contact“ of the switch.
Incomplete engagement, for example because the lever weight has not been brought fully into the end position, can override the tip lock. This means that the lock does not work and derailment or damage can occur unnoticed.
Highlights: Typical fastener types and their properties
- Clamp closure: low-maintenance, temperature-compensating, widely used
- Hook fastener: older, expensive to adjust, temperature-sensitive
- Joint closures / Jüdel closure: complex but suitable for long tongues
- Latch locks: modern, suitable for high-speed switches
At Bharat Forge CDP Railsystems, low-maintenance, precision-manufactured locking mechanisms are used and always designed in such a way that they can be integrated modularly into turnout projects.
Differences between tip lock, center lock & switch clamp monitoring
- Tip closure: secures tongue tip
- Center closure: required for long tongues distributed over the entire length
- Switch tester / latch: monitors position, prevents switch malfunction in the event of breakage or interruption of the setting device
Practice: Photo and video documentation & maintenance
Technicians use videos and photos to document the exact function of the lace fastener. Particularly relevant: visual inspection to ensure that the tongue is firmly in place, that there is no free movement and that the fastener can hook or latch. Regular inspection prevents long-term damage or deformation due to repeated repositioning.
The lace closure – small component, big responsibility
The point lock of a turnout is far more than just a mechanical detail – it is a central element for safety and operational reliability in rail operations. As the connection between the point and stock rail, it protects against misalignment, cutting, uncontrolled movement and signaling faults. It ensures that the direction of travel is correctly maintained, particularly in the case of switches with sharp points, even under thermal stress, vibration or heavy use in freight traffic.
Our turnout fasteners as a contemporary further development of the classic lace fastener
At Bharat Forge CDP Railsystems, we understand the importance of reliable locking systems for the safe functioning of turnouts, especially where switch blades need to be fixed precisely in the end position. While the classic clamp point lock is widely used in technical literature and practice, we rely on modern, technically advanced solutions such as our EVZ, WKV or BFL point locks.
These systems fulfill the same safety-critical function as a conventional point lock: they hold the switch blade permanently and positively on the stock rail, secure the position against external influences and enable trouble-free train operation. In combination with our VS-BF locking sleeper, we create a robust, durable and low-maintenance unit that can be reliably integrated into both new and existing projects.
Our point locks are therefore more than just a replacement for classic systems – they are a tried-and-tested further development that meets modern requirements in terms of ease of maintenance, compatibility and operational safety.
Conclusion: Systematic switch routing
The point lock is an inconspicuous but central component for the operational safety of turnout systems. It ensures that the point blade is reliably held in the selected end position, a basic prerequisite for safe and trouble-free train traffic. Whether mechanically simple or technically optimized: point locks make a decisive contribution to avoiding misalignments, preventing cutting and keeping the points functional under all operating conditions.
At Bharat Forge CDP Railsystems, we rely on high-performance turnout locking systems that meet the requirements of modern rail infrastructure and further develop the proven principles of classic locking technology. Our solutions combine positive locking, temperature tolerance and durability – and can be flexibly integrated into existing rail networks.
This turns a single component into a safety guarantor for the entire system. Because every detail counts in rail operations – especially when it comes to safe guidance in the turnout.
Are you planning rail infrastructure projects or are you about to renovate ancillary facilities, switch fields or overhead lines?
Then talk to us. Bharat Forge CDP Railsystems supports you with tried-and-tested technology, clear compliance with regulations and mechanical system solutions that function reliably even under demanding operating conditions.