Select BERG Spanntechnik clamping sets, grippers, and hydraulic cylinders for your machining requirements: from high-speed spindle retention to quick die change press units. Send part numbers, spindle types, or nameplate photos.
BERG clamping systems and accessories
Choose the clamping product group and specify interface parameters. Sizing new assemblies and sourcing replacement wear components require different technical inputs.
BERG steep taper grippers SSK and SSKV series
BERG steep taper (SK) clamping grippers provide reliable automatic tool retention in machining spindles. The SSKV series features integral mechanical force amplification, generating exceptionally high clamping forces from compact spring stacks.
The SSK, SSKE, SSKF, and SSKFI series provide direct force transmission. Berg SK grippers fully conform to DIN 69871, MAS 403-BT, and ANSI B5.50 (CAT) standards across shank sizes SK30, SK40, SK45, SK50, and SK60.
BERG hollow taper shank HSK clamping sets HK and HSH series
BERG HK and HKR series clamping sets are precision-engineered for hollow taper shank (HSK) tooling interfaces complying with DIN 69893 / ISO 12164. The HK/HKR mechanism incorporates integrated force amplification, ensuring simultaneous face and taper contact at extreme spindle speeds.
The HSH line delivers direct force clamping. Available for all HSK forms (A, B, C, D, E, F, T) across sizes HSK 25, 32, 40, 50, 63, 80, 100, 125, and 160 with wear-resistant coated gripper segments.
BERG polygonal taper shank PSC (Capto) clamping units
BERG clamping solutions for polygonal taper shank (PSC) tooling conform strictly to ISO 26623 (Coromant Capto standard). The CV and CVR lines incorporate mechanical force amplification engineered for automated tool changing in multi-tasking mill-turn centers.
The Capto C...(R) series provides direct-pull clamping. For static lathe turrets and manual tool blocks, BERG offers self-contained C...-M manual cartridges. Clamping sizes span C3, C4, C5, C6, C8, and C10 with high-pressure internal coolant capability.
BERG complete spindle tool clamping systems HS, MS and HDZK
BERG designs and manufactures complete, ready-to-mount tool clamping units for both motor spindles and gear-driven machining spindles.
These modular assemblies comprise the tool gripper, MS-series preloaded disc spring pack, hydraulic (HS-OHL) or hydromechanical (HS-SHR) release cylinder, and ES-ESK electromechanical actuators.
For mill-turn centers (including DMG MORI platforms powered by Kessler spindles), BERG provides compact HDZK clamping cylinder assemblies with built-in stroke sensing, fully factory-calibrated for clamping force and stroke limits.
BERG high-speed rotary unions KD-GDS and KD-8 series
BERG rotary unions provide continuous, leak-free transfer of water-miscible coolants, neat cutting oils, MQL aerosol, and dry compressed air through high-speed spindles.
The KD-GDS series features high-precision bearing support with a micro-gap controlled mechanical seal that withstands operating pressures up to 150 bar.
The bearingless KD-8 series is designed for ultra-high spindle speeds reaching 50,000 rpm and supports unrestricted dry running during spindle blow-out cycles.
BERG power-operated lathe chucks KHL, KH, KV and KHNC series
BERG workpiece clamping systems encompass precision power chucks engineered for heavy-duty metal turning. The three-jaw and two-jaw KHL and KH series feature large through-holes for bar stock processing.
The KV series is constructed with a closed center, delivering maximum torsional and radial body rigidity. KHNC chucks integrate a rapid-change jaw mechanism that reduces changeover times to minutes. Additionally, SG bar pullers automate unassisted stock feed inside the lathe work envelope.
BERG rotating hydraulic cylinders OHSR and OVR series
BERG rotating hydraulic cylinders convert hydraulic fluid power into dynamic axial drawbar force to actuate power chucks and expanding mandrels. The hollow-center OHSR series accommodates continuous bar passing through the main spindle bore.
The closed-center OVR and OVRK cylinders provide maximum force density for heavy chucking of castings and forgings. All models incorporate integral safety check valves to prevent accidental unclamping on line pressure drops, alongside inductive stroke position monitoring.
BERG quick die clamping systems for forming presses
For stamping presses, forging machines, and sheet forming lines, BERG delivers turnkey quick die change and clamping systems.
The portfolio encompasses BK and BKF mechanical and hydraulic wedge clamps for straight and tapered die clamping edges, PSP swing-clamp units, and self-travelling motorized clamping units that traverse along bolster and slide T-slots.
The range is completed by hydraulic slide locking units, automatic transfer rail couplings, and compact power units integrated with AS-Interface fieldbus control.
Information for equipment selection
Send spindle interface drawings, tooling taper standard (SK, HSK, Capto), required retention force, and hydraulic line pressure. Specify maximum operating speed and coolant delivery channels.
Spare parts and wear items
For installed machines, provide the machine model, serial number, 11-digit Ident-Nr., and photographs. For replacement gripper segments, provide tool taper and pull stud details.
Inspection and preventive maintenance of BERG tool grippers
Tool grippers across SSKV, SSK, and HK/HKR series operate under severe cyclic shock loads, high centrifugal acceleration, and continuous coolant flooding.
Regular preventive maintenance requires cleaning gripper segments from metal fines and solidified grease residues every 500 spindle operating hours. Technicians inspect the seating surfaces engaging the tool shank taper or AZB pull stud.
05 mm, or uneven segment contact are detected, replace the gripper assembly as a matched set. Proactive segment replacement prevents catastrophic tool ejection and protects the spindle taper bore against irreversible plastic deformation.
Spindle drawbar force monitoring using SKM and SSM gauges
Deterioration of preloaded disc spring stacks leads to subtle toolholder micro-movements under cutting pressure, resulting in poor surface finish, chatter marks, and chipping of expensive solid carbide tools.
Regular measurement using BERG SKM-Visio and SKMB digital pull force gauges with dedicated adapters for SK40, SK50, HSK-A63, HSK-A100, and Capto C6 is mandatory for precision manufacturing. The digital unit records static retention force and transmits data wirelessly to a handheld display.
When measured force drops by more than 15% below rated factory specification, overhaul the MS spring pack or hydraulic release seals.
Installation guidelines for HSK clamping sets HK and HKR
Mounting HSK clamping segments requires precise axial positioning of the drawbar relative to the spindle gauge face. The HKR force amplification mechanism utilizes kinematic wedges and sliding shoes that convert short axial drawbar stroke into tremendous radial clamping expansion.
Prior to assembly, thoroughly coat all sliding interfaces with high-pressure molybdenum disulfide paste to minimize sliding friction.
Following installation, verify smooth entrance and extraction of an HSK master gauge and inspect the face clearance gap between the tool flange and spindle nose prior to final drawbar clamping engagement.
Operation and troubleshooting of KD-GDS and KD-8 rotary unions
BERG rotary unions deliver coolant, air, and MQL media through high-speed spindles at fluid pressures reaching 150 bar and rotational speeds up to 50,000 rpm.
On bearing-supported KD-GDS models, monitoring the leakage drain port is critical: coolant droplets from the drain signal mechanical seal ring wear.
On bearingless KD-8 unions, silicon carbide seal faces separate automatically when media pressure is depressurized, enabling uncooled high-speed dry rotation and tool change air purge without seal friction. Ensure coolant filtration meets the 10-micron cleanliness threshold specified by BERG.
KHL and KH power chuck maintenance and jaw boring practices
Wedge-bar power chucks KHL and KH transfer massive clamping forces through ground sliding wedge bars. Centrifugal forces during high-speed turning tend to push master jaws outward against incoming chips and abrasive coolant.
Lubricate chuck guides daily through dedicated grease nipples using high-pressure lithium grease with extreme-pressure additives.
When retooling for new workpieces, bore or turn soft top jaws directly under hydraulic operating pressure using a dedicated boring ring to ensure true runout concentricity.
OHSR rotating hydraulic cylinders: safety and stroke control
OHSR cylinders actuate lathe chuck drawtubes and rotate with the spindle at speeds up to 6,000 rpm. Operator safety is ensured by integrated pilot-operated check valves that trap hydraulic pressure inside cylinder chambers if external supply hoses rupture.
An inductive proximity sensor ring mounted on the rear flange tracks forward and retracted stroke limits. Setting sensor positions accurately prevents machine spindle start-up if the workpiece is unclamped or improperly chucked.
Quick die change systems: BK wedge clamps and PSP swing clamps
On stamping and sheet forging presses, BERG BK/BKF wedge clamps and PSP swing clamps slash tool changeover downtime from hours to minutes.
BK wedge clamps incorporate a self-locking mechanical taper angle under 5 degrees, guaranteeing unyielding die retention on the press bed even under total power blackout and hydraulic line failure.
PSP swing clamps rotate their clamping arm 90 degrees before exerting up to 100 kN of clamping force per clamping point.
BERG clamping assemblies in DMG MORI and Franz Kessler spindles
BERG Spanntechnik is an established engineering partner for premier German machine builders.
In DMG MORI turning and milling centers (such as CTX beta, DMU, and NLX platforms) and Franz Kessler motor spindles (Compact Master, Speed Master), HDZK clamping cylinders and HK grippers serve as factory-fitted standard equipment.
When ordering replacement parts, providing the machine model, serial number, and 11-digit BERG Ident-Nr. 0) ensures complete plug-and-play interchangeability.
Disc spring stack inspection and drawbar overhaul criteria
Spindle disc spring stacks endure millions of rapid clamping and unclamping cycles. Fatigue failure of even a single spring washer introduces drawbar misalignment, accelerated internal friction, and severe clamping force decay.
During comprehensive spindle overhauls, technicians measure stack free length, loaded deflection, and check for micro-cracks along washer inner edges. Replacing worn stacks with factory-assembled, pre-calibrated BERG MS spring modules restores original spindle rigidity.
To obtain an accurate quotation for BERG clamping systems, replacement grippers, rotary unions, or hydraulic seals, provide the complete type designation and 11-digit Ident-Nr. stamped on the original part.
Our engineering team confirms cross-compatibility with spindle drawings and arranges fast shipment directly to your production facility with full manufacturer warranty and documentation.
Send your technical specification
SpareX organises clamping equipment selection and delivery quotation. Availability, compatibility, price, lead time, and documentation are confirmed for the specific unit configuration; we do not claim authorised BERG Spanntechnik dealer status.
