Sandvik HL820ST hydraulic rock drill is designed to ensure high drilling capacity, easy maintenance and low operating cost. The construction of the rock drill is based on the main body modules tied together with four short side bolts; this ensures a minimum number of joint faces and large contact surfaces. The percussion module is simple in design and consists of only two moving parts – the piston and the distributor sleeve around the piston and the moving parts are not in contact with the rock drill body modules.

Sandvik HL820ST is fitted with a drill stabilizer, which is designed to adjust percussion power according to variations in rock conditions which ensures good rock/bit contact and energy transfer, high penetration rate and rock tool service life.

There are two rotation motor variants to meet the rotation torque and RPM requirements of different hole diameters and rock formations. The optional power extractor is used for opening rock tool joints manually or automatically when using one-hole or fan automation and the design of the HL820ST is covered by several patents.

Technical data
Hole diameter range	54 - 89 mm
Kinetic power	21 kW
Percussion rate	42 - 53 Hz
Operating pressure Percussion Rotation	80 - 200 bar Up to 200 bar
Rotation motor type	OMT200 / 250
Stabilizer	Sleeve type
Shank length	600 mm

Rock tools and hole diameters
Thread	Rod mm	Hole mm
T35	39	54 - 57
T38	39	64
T45	46	76
T45	65 (tube)	76 - 89
T51	52	89