Drilling Line Care, Inspection and Replacement
Anything that moves is subject to wear, but much equipment wears out before its time due to neglect, abuse and operating practices.
Good inspection and replacement programs usually detect unsafe drilling line before it becomes an actual menace. Often, the ability of the drilling line to provide its expected service life is reduced by abrasion. Abrasion shows up first as small flat spots on the crown of the outside wires. If abrasion rate seems excessive, check equipment and operating methods. The following suggestions may reduce wear:
- Inspect new wire line reels when they arrive on location to see if any damage occurred to the line while being transported to the site. Also check to ensure that the proper size/type of drilling line was delivered.
- Wire reels and stands should be constructed strongly enough to prevent the stand from turning over and should have eyes, or slots for horizontal wire axis bar to keep the spool in place and eliminate the danger of the spool being pulled from the stand while unreeling.
- Protect unused line running from the reel to the substructure by the use of an overhead rack, track on the side of the catwalk, locating the drum reel close to the substructure, etc.
- Inspect sheaves and drum for roughened and corrugated areas.
- Inspect wire rope grooves to make sure they are not too narrow. Utilize sheave groove gauges to check wear in the grooves.
- Check for kinks and bends, which are common causes of deterioration.
- Check areas where drilling line may have been dragged over sharp edges or rough surfaces. This can be avoided by installing protective roller and guide sheaves.
- Keep heat sources such as welding/cutting away from the drilling line.
- Slip drilling line after a predetermined ton-mile point or use is reached.
Follow slip and cut safety procedures for replacing the drilling line and follow these guidelines:
- Use a string grip or snakeskin between the catline (old drilling line) and new drilling line. This will allow either line to twist and turn without passing the twist to the other line. Be sure that the grip is secure.
- While passing lines through the crown and traveling blocks, watch the line coming from the spool for kinks and fouling with other the objects. This could cause a hard stress and break the catline, dropping the drilling line and injuring members of the crew and ruining part of the line.
- After the desired lines are up, the line should be well clamped to the drum.
- Before removing the snakeskin from the new line, the end near the drawworks should be secured with sufficient loose line to allow attachment to the drawworks.
- When the line is clamped and the clamp is put in place, the chain used to secure the live end should be removed. Then start winding the desired wraps on the drum. The amount of wraps depends on the size of the drum and if the drum is smooth or grooved. Tension should be held on the line as it leaves the reel.
- Place the dead end around the drum of the wire line anchor and sleeve. The anchor drum, clamps and bolts that bolt it to the derrick or sills should be strong enough to stand the desired load. All clamps and positions of lines should be checked again before raising the traveling block.