Billet flame cleaning machine oxide skin, crack cleaning device design

From steel plate through a series of intermediate link reach incision workshop, during this period, the steel plate surface unavoidably produce a layer of oxide skin. Moreover, steel rolling process also produce in a layer of oxide skin attached to the steel plate surface. These oxide skin melting point, not easy high combustion and melting, increased preheating time, reduced the cutting speed; Meanwhile, after heating, oxide skin around the splash and extremely easily to cut caused jams, reduces the lips mouth using life. Cut So, in is necessary before cutting for steel surface derusting pretreatment.

Commonly used method is peen-forming derusting, after painting antirust. Upcoming shot peening machine with tiny iron ore, steel surfaces by soar into the impact of the of the steel iron ore remove oxide skin, spray flame retardant and electric conductivity good antirust paint.

Steel cutting the derusting spray-paint preprocessing before production of metal structure has become an indispensable tache.

In the actual production process, often have this or that kind of quality problem, generally has the following several defects: edge defects, cutting section defects, hang slag, crack, etc. The causes of the accident caused by quality, if oxygen purity guarantee many normal, in normal operation, then the flame cutting quality defects caused by reason mainly lie in the following aspects: cutting torch, cut the mouth, steel, steel material quality of itself.

1. The upper edge cutting quality defects

This is because the quality defect caused by the melting.

(1) on edge collapse edge

Phenomenon: melting too fast, causing rounded edge collapse edge.

Reason:

(1) the cutting speed too slow, preheat flame strong;

(2) the mouth and workpiece cut between highly too much or too little; The use of mouth number too big, cut the oxygen excess. Flame

(2) water droplets shape molten bean string (see chart 9-9)

Phenomenon: in cutting the upper edge of the form a string of water droplets form of melting beans.

Reason:

(1) the steel plate surface corrosion or have oxide skin;

(2) the steel mouth and cut between too high too small, preheat flame;

(3) the steel mouth and cut between highly too big.

(3) the upper edge of the present FangYan shape and collapse edge (see chart 9-10)

Phenomenon: in the upper edge of the FangYan incision, forming the bulge (collapse edge.

Reason:

(1) the preheating flame strong;

(2) the steel mouth and cut between highly too low;

(3) cutting speed too slow; Cut the height of mouth and between parts, the use of cut too large, too large, the mouth overcapacity. Oxygen in the preheated flame

(4) cutting section has hang the upper edge of the slag (see chart 9-11)

Phenomenon: cut on the edge sag and hangs slag.

Reason:

(1) the mouth and workpiece cut between highly too big, cut oxygen pressure is too high;

(2) the preheating flame is too strong.

2. Cutting section is uneven, namely flatness poor

(1) cutting edge on the cross, has sunken shape defects below (see chart 9-12) phenomenon: in accepting the edge cutting sections have cave, meanwhile the upper edge of the different levels of melting collapse edge.

Reason:

(1) cut oxygen pressure is too high;

(2) the mouth and workpiece cut between highly too big; Cut the mouth had sundry jams, make the wind line interference deformation.

(2) cut from top down contraction joints (see chart 9-13)

Phenomenon: cut to sew up wide below narrow.

Reason:

(1) cut too fast;

(2) the mouth and workpiece cut between highly too big, cut the mouth had sundry jams, make the wind line interference deformation.

(3) cut to sew up the narrow below wide (see chart 9-14)

Phenomenon: cut with narrow width, sewn into horn shape.

Reason:

(1) the cutting speed too fast, cutting oxygen pressure is too high;

(2), cut too large, the mouth that cutting oxygen flow too big;

(3) the mouth and workpiece cut between highly too big;

(4) cutting section sag (see chart 9-15)

Phenomenon: in the whole cutting section, especially have sunken intermediate place.

Reason:

(1) cut too fast;

(2) the use of mouth is too small, cutting pressure cut is too low, cut congestion or damage; mouth

(3) cutting too high, the wind line oxygen pressure thwarted worse.

(5) cutting sections show big corrugated shape (see chart 9-16)

Phenomenon: cutting section bumpy, appear larger corrugated shape.

Reason:

(1) cut too fast;

(2) the cutting oxygen pressure is too low, the mouth jam or damage, cut to the wind line deteriorate;

(3) the mouth, use cut is too big.

(6) incision of perpendicular direction Angle deviation (see chart 9-17)

Phenomenon: incision not vertical, appear bevel.

Reason:

(1) the torch with workpiece surface will not cut vertical;

(2) the wind line is not right.

(7) incision into round the lower edge (see chart 9-18)

Phenomenon: incision had different degrees of the lower edge of the melt into round shape.

Reason:

(1) mouth jam or damage, cut to the wind line deteriorate;

(2) the cutting speed too fast, cutting oxygen pressure is too high.

(8) incision under the lower sag and into rounded edge (see chart 9-19)

Phenomenon: close to lower edge sag under melting into fillet and edge.

Reason:

Cutting too fast, mouth jam or damage, cut the line go bad. Blocked

3. Cutting sections of roughness defects of cutting section directly influences the follow-up process roughness machining quality, the roughness and cut off the depth and volume of advanced tattoo concerned.

(1) after cutting section dragged dimension (FIG 9-20)

Phenomenon: cutting section cut grain backward migration is very big, at the same time as the size of the offset and appear different levels of depression.

Reason:

(1) cut too fast;

(2) the use of cut is too small, and cutting oxygen flow mouth too low, cutting oxygen pressure;

(3) the height of mouth and workpiece cut is too big.

(2) in the first half part, cutting sections appear cut lines leading quantity (see chart 9-21)

Phenomenon: the edge in close, forming a certain degree of cut lines leading quantity.

Reason:

(1) the torch and cutting direction not cut, cut congestion or vertical mouth damage;

(2) the wind line thwarted deteriorate;

Phenomenon: near the lower edge cutting sections appear cut lines leading quantity too big.

Reason:

(1) mouth jam or damage, cut thwarted deteriorate; the wind line

(2) the torch not cut vertically or cut mouth has a problem, make the wind line corruptive, tilt.

4. Hang slag in the lower edge cutting sections or to remove produced hang slag.

(1) the lower edge of the hanging slag (see chart 9-23)

Phenomenon: in the bottom edge cutting section produced continuous hang slag.

Reason:

(1) too fast or slow cutting, the use of cut, too small, cutting mouth too low oxygen pressure;

(2) in the preheated flame superfluous, steel surface gas oxide skin rust or not clean;

(3) the mouth and workpiece cut between highly too big, preheat the flame is too strong.

(2) cut on the cross hung slag produced

Phenomenon: there in cutting section hung next half part, especially slag has hang slag.

Reason:

Alloy content is too high.

5. Crack

Phenomenon: in cutting section, or appear on crack in cutting is the internal appear near the cross section, or just in pulsing crack to crack is visible on the transverse.

Reason:

Carbon content or contain alloy composition is too high, adopt preheating cutting method, workpiece preheated temperature enough, workpiece cooling time too fast, material cold hardening.