PULANKA Drill Rod Testing Report

PROJECT OVERVIEW

Testing Target

Through roadway excavation and scaling tests, evaluate the ultimate service life of the Pulanka drill rod (MF-T38-H35-R32, length: 4300 mm) and compare it with the service life of the rod from other brand, thereby assessing the general quality of the new Pulanka drill rod in terms of hardness, toughness, and other properties.

Overview of Construction at Testing Mining Area

This test is conducted at the Zaozhuang, Shandong Province mining area, where the construction type is Tunnel Excavation. A total of 14 Epiroc K111 drilling rigs are operating at this site, with 5 units on the day shift until 18:00 and 4 units on the night shift until 5:30 the next morning. The rock types mainly include biotite leptynite and amphibolite, partially mixed with magnetite amphibole ore, magnetite tremolite ore, and magnetite quartzite ore. The rock hardness is f=14–16, and the samples consist of both waste rock and ore.

Equipment Parameters

Drill Rig Model & Manufacturer: Epiroc K111
Rock Drill Model & Manufacturer: COP 1838HD+
Drill Rod Model & Manufacturer: MF-T38-H35-R32, Length 4300mm (Pulanka)
Shank Adapter Model & Manufacturer: Shank Adapter COP1838-435-T38 (Epiroc)

Drilling Parameters

1. Drilling Parameters:
The number of blast holes per single face is approximately 60, with a single hole depth of about 3.8 meters. Therefore, the total drilling meterage per round of blast holes is approximately 228 meters per drill rod.
2. Operational Performance Parameters:
Maximum impact power: 18 kW
Impact energy: 333 J
Impact frequency: 60 Hz
Maximum impact pressure: 230 Bar
Penetration rate:
In waste rock face: single hole drilling time ranges from 2:40 to 2:55, corresponding to a penetration rate of 1.36 m/min.
In ore face: single hole drilling time is 30 seconds slower than that in waste rock face, corresponding to a penetration rate of 1.15 m/min.

Competitor’s Usage & Condition

Typical service life of other common brand drill rods ranges from 9 to 11 blasting cycles with an average of 10 cycles. The average drilling footage per single rod is 2,280 meters. The failure mode of conventional drill rods upon end of service life is shown in Figure 1-1.

Figure 1-1 Failure Conditions of Competitor Drill Rods

Test Result of PULANKA Drill Rod No.1

Drill Rod No.1 completed 11 blasting rounds with a total tunneling footage of 2,508 meters. In the later stage, the rod body near the male thread was bent due to hazard elimination operations, resulting in final scrapping and failure. See Figure 2-1 for details.

2-1 Picture of Pulanka Drill Rod No.1

Test Result of PULANKA Drill Rod No.2

Drill Rod No.2 was used for 15 blasting rounds with total drilling footage of 3,420 meters, including 6 rounds in formation. It failed and was scrapped due to thread fracture in later service. Details are shown in Figure 2-2.

2-2 Picture of Pulanka Drill Rod No.2

Test Result of PULANKA Drill Rod No.3

Drill Rod No.3 completed 12 blasting rounds with total drilling footage of 2,736 meters, including 3 rounds in ore face and 9 rounds in waste rock face. It was scrapped owing to thread fracture in later operation.Details are shown in Figure 2-3.

2-3 Picture of Pulanka Drill Rod No.3

Comparative Test Summary

Based on the field test data, under regular working conditions, the average service life of Pulanka drill rods is over 600 meters longer than competing brands. This marks the first comparative test of Pulanka products; its measured performance is expected to improve further with stable on-site application going forward.

Drill Rod Test Data Comparison