---
title: "Foundation Engineering Supplier – Kelly Bars"
description: "Foundation engineering supplier: Kelly bars, drill rods, leaders & drilling tools to drawing — welded to DIN EN 1090-2 EXC3, machined up to 26 m."
url: "https://bock-gmbh.com/en/industries/foundation-engineering-drilling/"
language: "en"
index: "https://bock-gmbh.com/en/llms.txt"
---

# Foundation engineering & drilling: components to your drawing

As a foundation engineering supplier we manufacture welded and machined components for drilling and piling technology — Kelly bars, drill rods, leaders, drilling tools and piling rig components, manufactured to your drawing and to DIN EN 1090-2 EXC3 in Lorch in the Stuttgart region.
Kelly bars, drill rods, drilling tools and casing components for rotary and percussive drilling processes.
Shot blasting and industrial painting in the same plant — components leave production coated and ready to install.
Long rod and carrier components are machined in one setup.
Heavy piling rig and frame components — safe handling on the crane system with 2×25 t.
Load-bearing welds to the highest execution class certified in practice, plus EN ISO 3834-2.
VT, PT and MT by our own inspection personnel with Level 2 to DIN EN ISO 9712 — directly in production; UT at our plant by our cooperation partner.

## Your supplier for foundation engineering

As a foundation engineering supplier we manufacture to drawing — from the single part to the recurring small series. Components for drilling and piling technology are under combined load: Kelly bars and drill rods transmit torque and feed force while soil, gravel and rock work on the tool. Which material has to carry that is decided by your design — in practice it is predominantly structural steel. What comes from us is the manufacturing: dimensional accuracy over the full component length, documented welds and reproducible quality.
Piling rig components and load-bearing frame components have to absorb impact and vibration loads permanently. We weld such assemblies as a certified welding contractor to DIN EN 1090-2 EXC3 and EN ISO 3834-2 — with documented welds and seamless material traceability to EN 10204.
From the flame-cut blank through welding to CNC large-part machining, shot blasting and industrial painting, everything is produced under one roof in Lorch in the Stuttgart region. That shortens lead times, avoids external logistics between the manufacturing steps and keeps responsibility for schedule and quality in one place.
Heavy welded structures

## Typical components for foundation engineering

We manufacture to drawing and customer specification — welded, machined and documented:
- Kelly bars — telescopic drive bars for rotary drilling rigs, built for high torsional and feed loads
- Leaders, drill masts & booms — long welded mast assemblies and mast segments for piling and rotary drilling rigs, machined over the full length in one setup
- Drill rods & casing components — welded and machined components for drilling and casing systems
- Drilling tools — welded and machined tool bodies for rotary and percussive drilling processes
- Piling rig components — load-bearing frame components for continuous impact and vibration loading
- Sheet pile carriers & grab elements — heavy sections and assemblies, cut and machined ready to install
- Hose reels — for routing hydraulic and flushing hoses on drilling rigs
Further components to drawing on request — from the single part to the small series, with no minimum batch size.
Drill rods and mast assemblies — machined over the full length in one setup.

## Materials: what your design specifies

By far the largest share of the components we manufacture for foundation engineering is made from structural steel S235 and S355. We also process high-strength fine-grain steels and wear-resistant grades — where the design specifies them.
All grades are supplied with an inspection certificate 3.1 to EN 10204 — from our own stock of over 40 material grades, cut on flame-cutting systems with a 20 × 3.5 m table area up to 200 mm material thickness.

## Machining up to 26 m component length

Kelly bar components, drill rods and sheet pile carriers are long — and demand dimensional accuracy over the full length. On two Zayer gantry milling centres we machine components up to 26 m in one setup; the 30° swivel milling head reaches several machining planes without repositioning.
Very long & dimensionally accurate
X travel 26,000 mm — machining over the full component length in one setup.
e.g. sheet pile carriers and rod components in extra length
Connection & functional faces
30° swivel milling head for mating faces and hole patterns in several planes without repositioning.
e.g. connection and bolting faces on piling rig frames
Material to your specification
Structural steel as well as higher-strength grades — cut, welded and machined in the same plant.
e.g. drilling tools with machined functional faces

## Impressions from foundation engineering

Real photographs from our shop floor in Lorch – from the welded drum body with its grooved barrel, through the complete hose drum for hydraulic and flushing hose guidance, to the front view of its spoked flange.

## Quality & testing for drilling and piling technology

Load-bearing welded structures for foundation engineering are welded to DIN EN 1090-2 EXC3 — the highest execution class certified in practice — and EN ISO 3834-2. Every heat stays traceable through material marking to EN 10204; we are authorised by GSI SLV München to re-stamp.

### Non-destructive testing in-house

Components under impact and abrasive loading require welds that are demonstrably free of defects. We therefore test where we manufacture — with no external waiting times.
- Visual (VT), dye penetrant (PT) and magnetic particle (MT) testing by our own inspection personnel with Level 2 to DIN EN ISO 9712 — directly in production in Lorch.
- Ultrasonic testing (UT) is carried out at our plant on a project basis by certified inspection personnel of our cooperation partner. Material tests such as tensile tests and notched-bar impact tests are carried out through an external test laboratory where required — depending on the standard and acceptance specification. Volumetric testing (radiographic testing RT, ultrasonic testing UT) is, insofar as commissioned, provided by qualified partners.
We agree the scope of testing and documentation project by project, based on drawing, standard and customer specification — from the inspection certificate 3.1 to the certified re-stamping certificate.
Non-destructive testing in detail

## Why Bock as your supplier in foundation engineering

- From batch size 1
- Single part, spare part or recurring small series — with no minimum batch size, manufactured to your drawing.
- Heavy & long
- Components up to 50 t part weight and 26 m in length — safe handling on the crane system with 2×25 t.
- Certified & traceable
- DIN EN 1090-2 EXC3, EN ISO 3834-2 and an inspection certificate 3.1 to EN 10204 — re-stamping authorised by GSI SLV München.
- Everything from a single source
- Flame-cut blanks, welding, machining, shot blasting and industrial painting in the same plant — with no external logistics between the steps.
- Since 1963
- 63 years of manufacturing experience, 100+ specialists and 14,000 m² of production space in Lorch in the Stuttgart region.

## Frequently asked questions — foundation engineering

### Does Bock manufacture Kelly bars and drill rods to drawing?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-fertigt-kellystangen-bohrgestaenge

Yes. We manufacture Kelly bars, drill rods, drilling tools and other drilling technology components to your drawing and in the specified material — welded to DIN EN 1090-2 EXC3 and machined up to 26 m component length. As a contract manufacturer we work exclusively to customer specification, from the single part to the small series.

### Does Bock manufacture leaders, drill masts and booms for piling and drilling rigs?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-fertigt-maekler-bohrmasten-ausleger

Yes. Mast assemblies for piling and rotary drilling rigs are part of our core business — leaders and guide masts, drill masts and mast segments as well as telescopic and boom structures. Manufacturing follows your drawing: welded to DIN EN 1090-2 EXC3, machined up to 26 m component length in one setup and up to 50 t part weight. On request including shot blasting, industrial painting and an inspection certificate 3.1 to EN 10204.

### Which materials are used in foundation engineering?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-werkstoffe-kommen-spezialtiefbau-einsatz

Predominantly structural steel S235 and S355. We process high-strength fine-grain steels or wear-resistant grades when your design specifies them. Supply comes from our own stock of over 40 material grades — each with an inspection certificate 3.1 to EN 10204.

### Up to what size and weight do you manufacture?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-groesse-welchem-gewicht-gefertigt

Up to 50 t part weight and 26 m component length. The crane system with 2×25 t allows safe setting up and turning of heavy blanks; long components are machined on gantry milling centres in one setup.
CNC large-part machining

### How are welds on drilling technology components tested and documented?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-schweissnaehte-bohrtechnik-bauteilen

Load-bearing welds are welded to the requirements of EXC3; testing is carried out in-house by visual, dye penetrant and magnetic particle testing by our own Level 2 personnel to DIN EN ISO 9712; ultrasonic testing is performed at our plant by our cooperation partner. On request we document with an inspection certificate 3.1 and a re-stamping certificate to EN 10204.

### Does Bock also repair worn drilling tools and assemblies?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-setzt-verschlissene-bohrwerkzeuge

Yes. Worn, cracked or damaged steel assemblies are repaired up to 50 t part weight — weld repair, build-up and hardfacing welding, machining rework as well as blasting and painting, including for other manufacturers' equipment.
Repair & refurbishment

### Where does Bock manufacture as a foundation engineering supplier and which area is supplied?

URL: https://bock-gmbh.com/en/industries/foundation-engineering-drilling/#spezialtiefbau-faq-fertigt-spezialtiefbau-zulieferer

Manufacturing takes place entirely in the Lorch plant in the Stuttgart region — cutting, welding, machining and surface finishing under one roof. We supply customers in southern Germany and throughout the DACH region.

## Looking for components for foundation engineering?

Send us your drawings — we will assess manufacturability, clarify open points on material and tolerances and prepare a no-obligation quote.
Certified to DIN EN 1090-2 EXC3 · inspection certificate 3.1 to EN 10204.