# @stem_antics on Instagram

- **Type:** Video
- **Original URL:** https://www.instagram.com/p/DdwWsuoACur
- **Gondola URL:** https://gondola.cc/posts/70844131-stem-antics-instagram
- **Thumbnail:** https://img.gondola.cc/tr:w-,h-,fo-auto/postThumbnails/b909422ed8.jpg
- **Posted:** 2026-09-26T15:27:56.000+00:00
- **Account Owner:** Stem Antics (@stem_antics) — https://gondola.cc/stem_antics

## Caption

Every blow of a diesel pile hammer is a single stroke of a two-stroke engine in which the pile itself acts as the crankshaft.

The machine is simple in structure: a vertical steel cylinder, a heavy free-falling ram acting as the piston, and an anvil or impact block seated on the pile head. There is no flywheel, no connecting rod and no external power supply once it is running. The cycle is self-sustaining:

- The ram is lifted by a trip mechanism on the crane and released
- As it falls, it closes the exhaust ports and compresses the trapped air
- Fuel is injected onto the impact block just before contact
- The ram strikes the anvil, driving the pile and atomising the fuel into the hot, compressed air
- The mixture ignites, adding a second push to the pile and launching the ram upward
- The exhaust ports reopen, spent gas escapes and fresh air is drawn in
- Gravity returns the ram and the cycle repeats, typically 35 to 60 blows per minute

Delmag, based in Esslingen, Germany, brought the concept into commercial use in the 1930s, and it went on to dominate foundation work for decades because it is portable, self-contained and remarkably tolerant of rough site conditions.

The most interesting behaviour is how the hammer responds to the ground. Rated energy is roughly ram weight multiplied by stroke height. In hard driving the pile resists strongly, combustion throws the ram higher and energy per blow rises. In very soft soil the pile yields too readily, compression is poor, and the hammer can stall entirely. The ground partly sets the output of the engine.

Rams range from under a tonne for light sheet piling to more than 20 tonnes on the largest units, delivering enough energy per blow to seat steel piles for bridges, ports and offshore platforms.

The soil does not only receive the energy, it helps decide how much arrives.

#stemantics #civilengineering #geotechnicalengineering #mechanicalengineering #construction

## Stats

- **Views:** 134,700
- **Likes:** 1,442
- **Shares:** 0
- **Comments:** 2

## Tags

construction, civilengineering, mechanicalengineering, stemantics, geotechnicalengineering

---
Copyright (c) Gondola