By servicing the oil and gas industry, Rushing Machine Shop has found its own niche in metalworking. Since Leon Rushing founded the east Texas company in 1978, it has grown to include more than 25,000 square feet of manufacturing space, housing 22 CNC machines and 40 full-time employees. Having witnessed the many highs and lows of the oil industry, Mr. Rushing has maintained a successful business over the years by doing everything possible to reduce turnaround time for customer orders.
Most recently, Mr. Rushing was faced with the challenge of integrating several new machines and delivering high-volume parts orders in a timely manner to several of his established customers. On one of these jobs, a problem arose when the shop experienced difficulty with one slotting application. It needed to reduce cycle time and eliminate costly tool replacements while adding stability to the process.
The shop had tried several different cutting tools without success. Data showed that during a 16-month time period, Rushing had incurred a large amount of tooling cost and needed to seek an alternative solution. The task consisted of cutting a slot on both sides of a hanger body with a 5 1/2-inch ID. The slot measured 0.75-inch wide, 0.875-inch deep and 3 inches long. The shop was going through a significant number of tools to machine each part, and it was achieving only 23 parts per cutting edge at 2.85 ipm. Additionally, chip evacuation issues were causing frequent tool failure.
To help improve efficiency and reduce tooling costs, the shop asked a representative from cutting-tool manufacturer Iscar to examine the part and process. After analyzing the situation, the representative suggested bringing in Iscar’s new Tangslot cutter for a test.
Designed for operations that require accurate slotting and grooving, the Tangslot is suited for the energy and automotive industries for general slotting applications involving bearing caps, steering knuckles, connecting rods and other components. Unlike the shop’s previous tool, the Tangslot’s LNET 12.. Inserts are tangentially mounted, meaning they lie in pockets parallel to the tool face. This reduces pressure on the mounting screws to allow high feed rates. Combined with tangential mounting, the shape of the inserts themselves results in a narrow slotting cutter with a fine pitch.
Positive, rake-face chipformers on the each insert’s two right-hand and two left-hand cutting edges reduces cutting forces and power consumption by 15 to 20 percent, the company says. In addition, the inserts are staggered on the tool and designed to direct chips inward toward the center of the cutter rather than outward toward the side walls. This keeps chips away from the cutting area, increasing tool life and leaving side surfaces unscratched for a better finish, the manufacturer says.
The cutter provided the savings in overall production cost that the Rushing Machine Shop production team sought. The tool achieved 5.55 ipm compared with the previous 2.85 ipm, and tool life increased. The number of pieces produced per cutting edge increased from 23 to 120 pieces with the new tool. In addition, tool failure is no longer an issue because the tool life of the Tangslot is more consistent than the previous slotting cutter.