Professional Photography Shockproof Suitcase (Pelican / Nanuk) Foam Custom Cutting and Pressure Balance Valve Operation

1. Why do expensive precision equipment have to be put in a "military-standard three-proof safety box"?

Photographers ride on commercial airliners, jolt through the Gobi Desert on the Qinghai-Tibet Plateau in the trunk of an off-road vehicle, or conduct field scientific research in heavy rain and mud:

1. Extreme shortcomings of soft nylon camera bags:

• The soft bag can only protect against slight bumps; once it is squeezed by a hard box weighing tens of kilograms on the shipping conveyor, or is dropped from a height of 1.5 meters on the cement floor, the impact force will instantly penetrate the fabric, and the body bayonet will be broken and bent by the lens gravity lever on the spot, and the optical axis of the lens group will be completely deflected and scrapped.

2. Pelican/Peli Case Physical Armor Myth:

• The shell is made of patented high-impact modified copolymer polypropylene (HPX / Polypropylene Resin) and is integrally injection molded;
• The box structure is covered with reinforced ribs, which can withstand the gravity of trucks (bearing several tons) without breaking and deforming;
• Meets the U.S. military standard MIL-STD-810G drop and shock resistance and IP67 absolute dustproof and waterproof rating (no water leaks inside the box when immersed under 1 meter for 30 minutes).

2. The physical mystery of the Automatic Pressure Equalization Valve

After landing on a plane, many photographers who were using professional protective boxes for the first time found that no matter how much force they exerted with their hands, the box still seemed to be welded shut after the lid buckle was opened and could not be pulled out**:

1. High air pressure difference and large physical phenomenon of vacuum self-locking:

• When the aircraft is cruising at high altitude, the air pressure in the cargo compartment decreases (equivalent to an altitude of two thousand meters);
• As the aircraft landed at high speed, the atmospheric pressure on the ground increased sharply, causing the air pressure outside the box to be much higher than the low air pressure inside the box!
• The huge difference in internal and external air pressure generates a powerful net pressure of up to thousands of Newtons (equivalent to hundreds of kilograms) on the surface of the box cover that is tens of centimeters wide, and the box cover with the rubber sealing ring is pressed tightly together and sucked to death.

2. Physical mechanism of Gore-Tex Membrane Valve:

• There is a circular automatic air pressure balance valve installed next to the handle on the front of the box;
• A piece of microporous polytetrafluoroethylene (ePTFE) expanded waterproof and breathable membrane is embedded in the inner core of the valve;
• Magical pore size selectivity: The diameter of the film micropores is 20,000 times smaller than that of water molecule clusters (liquid water and dust are absolutely impenetrable), but thousands of times larger than air gas molecules!
• Gas molecules can freely move in and out driven by the air pressure difference to balance the internal and external pressure, ensuring that a negative pressure vacuum is never generated in the box. After landing, the lid can be opened smoothly with one hand at any time, while maintaining 100% absolute waterproof immersion.

3. Pre-cut small square sponge (Pick'N'Pluck) planning and custom cutting to avoid pits

The three-layer high-density polyurethane foam that comes in the box is pre-die-cut into thousands of tiny 1cm $\times$ 1cm square columns:

1. Principles of space planning for equipment arrangement:

• Place all the fuselage, large three-dimensional lens, drone, battery, and charger that need to be installed neatly on the surface of the sponge;
• Bottom line rule for safe distances: At least 2 to 3 blocks (about 2.5cm~3.5cm) of sponge buffer wall must be left between any two pieces of heavy metal equipment!
• It is strictly forbidden to allow two metal lenses to be squeezed together with only a thin layer of sponge separated by them. Otherwise, the sponge will be penetrated during a violent drop and impact, and the two lenses will collide violently and break inside.

2. Trilogy of "pre-marked lines-vertical tear-off-bottom reinforcement":

• Use a pin or toothpick to insert a full circle along the outer contour of the equipment to mark the physical positioning;
• Take out the equipment, apply force vertically downwards with the thumbs of both hands, and tear vertically downwards along the pre-cut slit, tearing out an exclusive deep groove that closely matches the outer contour of the equipment;
• Anti-tear-off glue coating on the bottom layer of sponge (Plasti Dip spray curing magic technology):
• Ordinary square sponges will continue to fall off and break around the edges after being used for a long time;
• Top Player Tips: After all the grooves are removed from the sponge, take out a can of Colorless/Black Plasti Dip Flexible Liquid Rubber Self-Spray Paint and spray evenly on the surface of the sponge and the inner wall of the groove 3 times!
• After curing, an extremely tough, wear-resistant and scratch-resistant integrated rubber protective layer is formed on the surface of the sponge. After ten years of use, the square sponge is still neat and neat, with no slag or chips!

4. Modern advancement: TrekPak modular plug-in system and civil aviation boarding size (Pelican 1510)

1. The space-doubling miracle of the TrekPak bulkhead system:

• Traditional thick foam takes up up to 40% of the box’s valuable internal volume;
• The modern top solution is fully upgraded to the TrekPak modular system: extremely high-strength double-walled corrugated acid-free plastic panels are thermally bonded to dense closed-cell foam on both sides, with a thickness of only 1 cm;
• Equipped with a special metal U-shaped latch and a micro-cutting double-edged knife, you can freely cut out a square space and hold a full 30% more lens equipment than traditional sponges**.

2. Limited dimensions of civil aviation carry-on suitcases (Carry-On specifications):

• Photography equipment must not be checked in easily;
• The maximum carry-on suitcase size according to the global civil aviation overhead luggage rack standard corresponds to the Pelican model: Pelican 1510 / Nanuk 935;
• The external length, width and height are strictly controlled at 55.9 $\times$ 35.1 $\times$ 22.9 cm, which can be seamlessly pushed directly onto the Boeing 737 / Airbus A320 economy class overhead luggage rack, keeping millions of equipment within sight and guarded by both hands at all times.