JET CHISEL

A jet chisel (also called needle scaler) is a pneumatic tool made up of multiple thin steel rods (“needles”) that rapidly move back and forth when connected to compressed air. The vibration of the needles chips away rust, old paint, scale, and marine growth on metal surfaces. Think of it as “pangbaklas ng kalawang, pero industrial version.” Purpose: • Remove rust, corrosion, and scale from steel surfaces • Prepare metal before painting, welding, or coating • Clean areas where grinders and wire brushes can’t reach (corners, tight spots, edges) • Reduce manual scraping time and physical fatigue How to Use: 1. PPE First • Safety goggles / face shield • Ear protection (maingay ’yan) • Gloves • Mask (dust/rust particles) • Proper coverall 2. Check the Tool • Inspect air hose, connectors, and needles • Ensure air compressor pressure is within recommended range (usually 90 psi ± depending on tool) 3. Connect to Compressed Air • Attach hose firmly • Open the air valve gradually 4. Operate • Hold the tool with both hands • Press the needles gently against the surface — do not push too hard • Let the vibration do the work • Work in steady strokes 5. After Use • Shut off air supply • Clean and oil the needles to prevent rust • Store in dry location

Lathe Machine

LATHE MACHINE; THE MOTHER OF ALL MACHINES A lathe machine is a powerful tool in both industrial and maritime workshops. By rotating a workpiece against a cutting tool, it enables precise shaping, drilling, and finishing of materials. This makes it vital for manufacturing components such as shafts, propeller parts, and other cylindrical items that require high accuracy. How a Lathe Machine Works At its core, a lathe machine consists of a headstock, tailstock, bed, and carriage. The headstock houses the spindle and speed controls, delivering rotational motion to the workpiece. The tailstock provides support and can hold auxiliary tools like drills or reamers. The bed acts as a rigid base, ensuring that all other components remain aligned. Mounted on the bed, the carriage including the saddle, cross-slide, and tool post movably carries the cutting tool, while the lead screw and feed rod drive the tool’s motion for threading and feeding. Operations You Can Do on a Lathe Lathes are extremely versatile. Here are some of the most common operations: Turning: Reducing the diameter of a workpiece to form cylinders or tapered shapes. Facing: Creating flat surfaces on the ends of the piece. Parting: Cutting off a portion of the workpiece. Boring: Enlarging existing holes or providing a precise internal diameter. Thread Cutting: Cutting internal or external screw threads. Knurling: Forming patterned grips on handles or tool surfaces. Drilling: Using a drill held in the tailstock to bore holes with high accuracy.

MARINE MAIN ENGINE

Marine Main Engine The marine main engine is the heart of a ship’s propulsion system. It is the largest and most powerful machine on board, designed to convert fuel into mechanical energy that turns the propeller and drives the vessel forward. Without it, modern shipping—responsible for carrying around 90% of the world’s trade—would not be possible. Understanding the main engine is essential for students, seafarers, and anyone interested in marine engineering. Meaning and Purpose The main engine refers to the primary source of propulsion power in a ship. Its purpose is straightforward yet vital: to provide continuous, reliable thrust to move the vessel safely across oceans. Unlike auxiliary engines, which generate electrical power for onboard systems, the main engine directly powers the propeller shaft. This distinction highlights its role as the core machinery that ensures a ship’s mobility and operational efficiency. Background Marine engines have evolved significantly since the early days of steam propulsion. In the 19th century, ships relied on coal-fired steam engines. Over time, these were replaced by more efficient internal combustion engines. Today, the most common propulsion system in large commercial vessels is the two-stroke low-speed diesel engine, valued for its efficiency, durability, and ability to burn heavy fuel oil. However, with increasing environmental regulations, new technologies and alternative fuels are reshaping the future of marine propulsion.

Tropical cyclone categories

Tropical cyclone categories are used to classify storms based on their maximum sustained wind speed, the level of damage expected at landfall, and the height of storm surge they can produce. This standardized system helps meteorologists, mariners, and coastal communities quickly understand a cyclone’s intensity and the potential risks it poses. As the category number increases, the storm becomes more powerful, more destructive, and more dangerous to life, property, and maritime operations. ‣Category 1 cyclones have wind speeds of 74–95 mph and typically cause minimal damage. Some roof damage, broken branches, and minor coastal flooding may occur. Storm surges range from 4–5 feet. ‣Category 2 cyclones produce winds of 96–110 mph and cause moderate damage. Trees may be uprooted, windows broken, and power outages are common. Storm surges reach 6–8 feet. ‣Category 3 cyclones are major storms with winds of 111–129 mph. Extensive damage occurs, including structural damage to buildings and serious coastal flooding from 9–12 feet of storm surge.