GB2213902A

GB2213902A - Replacing diesel injector pipes

Info

Publication number: GB2213902A
Application number: GB8729359A
Authority: GB
Inventors: Geoffrey Hartland
Original assignee: C V P
Current assignee: C V P
Priority date: 1987-12-16
Filing date: 1987-12-16
Publication date: 1989-08-23
Also published as: GB8729359D0

Abstract

A means which permits ready replacement of a broken or damaged injector pipe of a diesel engine comprises a precursor pipe 10 in the form of a length of tubing the end portions of which carry connection means 11, 12 which permit connection respectively to the fuel pump and to a fuel injector of the engine, the tubing being of a material (eg. mild steel or reinforced plastics) such that it can be manipulated manually by the driver into a shape which permits said connection of the tubing end portions to the pump and said injector. A kit comprising two or more selected precursor pipes enables any injector pipe of a diesel engine which may become damaged to be replaced. <IMAGE>

Description

REPAIR OF DIESEL ENGINES This invention relates to injector pipes in precursor form for use with diesel engines and to kits containing such articles. The invention is concerned particularly with the repair of diesel engines.

A problem commonly met in the operation of diesel vehicles, particularly diesel lorries, is the accidental fracture of the injector pipes which convey diesel oil from the fuel pump to the respective injectors of the engine. When such fracture occurs while the vehicle is on the road it results in its immobilisation until a replacement pipe can be obtained. Owing to the different dispositions of the respective injectors of an engine to the fuel pump, it is usually the case that the length and/or shape of the injector pipes of a given diesel engine are different from one another.

Therefore, it is not normally practicable for a vehicle to carry a complete set of replacement injector pipes so as to permit ready replacement of a broken pipe when required. Instead, it is necessary for the lorry driver to take emergency action by calling on a breakdown service; and this action is not only expensive so far as the cost of the service and replacemement is concerned, but more important is the resulting delay to the progress of the vehicle and the resulting difficulty experienced by the driver in keeping to his scheduled journey. This is particularly important, for example, where the lorry is to be conveyed at a particular time by a marine ferry boat or otherwise has to keep to a pre-planned schedule.In the case of prolonged delays in replacing a fractured injector pipe the lorry driver may be unable to complete his journey without stopping for a rest period as required by law.

Moreover, as the shape and/or dimensions of injector pipes differ also from one make of engine to another and even between different models of the same manufacturer it has, hitherto, been impracticable to provide a single kit of replacement injector pipes to suit all types of diesel engines.

There has now been devised, according to the present invention, a means which permits ready replacement of a broken or damaged injector pipe without the need to have at hand an injector pipe in the shape of the pipe to be replaced.

Accordingly, in a first aspect the invention provides a precursor injector pipe which comprises a length of fuel supply tubing the end portions of which carry connection means which permit said end portions to be connected respectively to the fuel pump and to a fuel injector of a diesel engine, the fuel supply tubing being of a material such that the tubing can be manipulated manually into a shape which permits said connection of the tubing end portions to the fuel pump and to said injector.

In a second aspect the invention provides a kit for use in the repair of diesel engines, which comprises: two or more precursor injector pipes adapted respectively to fit two or more combinations of fuel pump and fuel injector, each precursor being sufficiently flexible as to be formable by hand into an injector pipe of a suitable shape to permit the inter-connection of the fuel pump and said fuel injector.

The term "precursor injector pipe" as used herein serves to distinguish a pipe of the invention from a pipe which has been formed from the precursor so that its shape or geometry is such that it is suitable for the inter-connection of a fuel pump and an injector of a diesel engine. The pipes so formed are referred to herein as "injector pipes".

The precursor injector pipes of the present invention are conveniently linear in shape thereby facilitating their transport and storage. Moreover, the production of the precursor pipes is normally more convenient if they have a linear shape. However, the invention is not limited to precursor injector pipes in linear form: the precursor pipes can take any other suitable shape, for example, as a semi-circle or other arc shape. The term "arc" as used herein includes not only portions of circles but also portions of ellipses, parabolas and other geometric shapes.

Moreover, the precursor pipes of the present invention are not limited to pipes lying in a single plane.

However, for the reasons given above, it will generally be found convenient to manufacture, transport and store the precursor pipes in linear form. Examples of such forms are given in the Examples which follow.

An important feature of the present invention is that the precursor pipes have a modulus such that they can be shaped using a degree of manual force which will be found acceptable or at least tolerable by the driver of the diesel vehicle.

The tubing of the precursor pipes is normally a metal so as to withstand the considerable pressure exerted by the diesel oil as it is pumped to the injectors.

Suitable tubing or pipework used for the precursor pipes of the invention is of cold drawn seamless steel.

(by way of example) Details of suitable tubing are included/in the following table; in particular, a suitable tubing is that having an outside diameter of 6.00mm a wall thickness of 2.OOmm and a weight of 0.197kg/m. These tubings meet british Specification 3602:1978 Part 1 as indicated.

Recommended Maximum Working pressure (bar) Out Wall Weight Lb Safety Factor Safety Factor Safety Factor Dia Thick Per 2.5-1 3.0-1 4.0-1 mm mm kg/m lb/ft Bar* lbf/in2 Bar* lbf/in2 Bar* lbf/in2 6.00 1.00 .123 .083 470 6.800 390 5.650 290 4.200 6.00 1.50 .166 .112 710 10.250 600 8.700 440 6.350 6.00 2.00 .197 .132 950 13.750 790 11.450 590 8.550 8.00 1.00 .173 .116 350 5.050 300 4.350 220 3.150 8.00 1.50 .240 .161 530 7.650 440 6.350 330 4.750 8.00 2.00 .296 .199 710 10.250 600 8.700 440 6.350 8.00 2.50 .339 .228 890 12.900 740 10.700 550 7.950 10.00 1.00 .222 .149 280 4.050 230 3.300 170 2.450 10.00 1.50 .314 .211 420 6.050 350 5.050 260 3.750 10.00 2.00 .395 .265 560 8.100 470 6.800 350 5.050 10.00 2.50 .462 .310 710 10.250 600 8.700 440 6.350 10.00 3.00 .518 .348 860 12.450 710 10.250 530 7.650 10.00 3.50 .561 .377 1.000 14.500 830 12.00 620 8.950 10.50 2.25 .458 .308 610 8.800 500 7.250 380 5.500 12.00 1.00 .271 .182 230 3.300 190 2.750 140 2.000 12.00 1.50 .388 .261 350 5.050 300 4.350 220 3.150 12.00 2.00 .493 .331 470 6.800 390 5.650 290 4.200 12.00 2.50 .566 .394 590 8.550 490 7.100 370 5.350 14.00 1.00 .321 .216 200 2.900 160 2.300 120 1.700 14.00 1.50 .462 .310 300 4.350 250 3.600 180 2.600 14.00 2.00 .592 .398 410 5.900 340 4.900 250 3.600 15.00 1.50 .499 .335 280 4.050 230 3.300 170 2.450 15.00 2.00 .641 .431 370 5.350 310 4.450 230 3.300 16.00 1.50 .536 .360 260 3.750 220 3.150 160 2.300 16.00 2.00 .691 .464 350 5.050 300 4.350 220 3.150 16.00 2.50 .832 .559 440 6.350 360 5.200 270 3.900 16.00 3.00 .962 .646 530 7.650 440 6.350 330 4.750 16.00 3.50 1.060 .725 620 8.950 520 7.500 390 5.650 18.00 1.00 .419 .282 150 2.150 130 1.850 90 1.300 18.00 1.50 .610 .410 230 3.300 190 2.750 140 2.000 18.00 2.00 .789 .539 310 4.450 260 3.750 190 2.750 18.00 2.50 .355 .042 390 5.650 320 4.600 240 3.450 20.00 1.50 .664 .460 200 2.900 170 2.450 130 1.850 20.00 2.00 .888 .597 260 4.050 230 3.300 170 2.450 20.00 2.50 1.080 .725 350 5.050 300 4.350 220 3.150 20.00 3.00 1.260 .845 420 6.050 350 5.050 260 3.750 20.00 4.00 1.580 1.060 560 8.100 470 6.800 350 5.050 22.00 1.50 .758 .509 190 2.750 160 2.300 120 1.700 22.00 2.00 .986 .663 250 3.600 210 3.000 160 2.300 22.00 2.50 1.200 .808 320 4.600 270 3.900 200 2.900 22.00 3.00 1.410 .945 380 5.500 320 4.600 240 3.450 22.00 4.00 1.780 1.190 510 7.350 430 6.200 320 4.600 25.00 2.00 1.130 .762 220 3.150 180 2.600 140 2.000 25.00 2.50 1.390 .932 280 4.050 230 3.300 170 2.450 25.00 2.80 1.530 1.030 310 4.450 260 3.750 190 2.750 25.00 3.00 1.630 1.090 340 4.900 280 4.050 210 3.000 25.00 4.00 2.070 1.390 460 6.650 380 5.500 280 4.050 25.00 4.50 2.280 1.530 510 7.350 420 6.050 310 4.450 28.00 1.00 .666 .448 100 1.450 80 1.150 60 850 28.00 1.50 .980 .659 150 2.150 120 1.700 90 1.300 28.00 2.00 1.280 .861 200 2.900 160 2.300 120 1.700 28.00 2.50 1.570 1.060 250 3.600 200 2.900 150 2.150 28.00 3.00 1.850 1.240 300 4.350 250 3.600 180 2.600 30.00 2.00 1.380 .928 180 2.670 150 2.150 110 1.550 30.00 2.50 1.700 1.140 230 3.300 190 2.750 140 2.000 30.00 3.00 2.000 1.340 280 4.050 230 3.300 170 2.450 30.00 4.00 2.570 1.720 370 5.350 310 4.450 230 3.300 30.00 5.00 3.080 2.070 470 6.800 390 9.650 290 4.200 35.00 2.00 1.630 1.090 150 2.150 130 1.850 90 1.300 35.00 2.50 2.000 1.350 200 2.900 160 2.300 120 1.700 35.00 3.00 2.370 1.590 240 3.450 200 2.900 150 2.150 38.00 3.00 2.590 1.740 220 3.150 180 2.600 140 2.000 38.00 4.00 3.350 2.250 300 4.350 250 3.600 180 2.600 38.00 5.00 4.070 2.730 370 5.350 310 4.450 230 3.300 40.00 5.00 4.320 2.900 350 5.050 300 4.350 220 3.150 40.00 6.00 5.030 3.380 420 6.050 350 5.050 260 3.750 42.00 2.00 1.970 1.330 130 1.850 110 1.550 80 1.150 42.00 3.00 2.890 1.940 200 2.900 160 2.300 120 1.700 The tubing referred to in the Table is designed for hydraulic and pneumatic lines. It has the following features: B.S.3602:1978 Part I CFS 360 Cat 2, DIN 2391 ST 35.4NBK.

Random Lengths : 4.3-6.5m (14-21ft) Tolerances to B.S.3602 Part 1:1978 clause 11.1(e) Tubes for use with compression couplings.

Eddy current tested Normalised (free from scale) Test certificates available on request Ends capped * 10 Bar = lN/mm2 -N- 145 lbf/in2 (psi) Although mild steel of "hydraulic" quality is the preferred material for the tubing, the present invention does not exclude other materials, for example reinforced plastics materials, provided that they ca-n safely withstand the working pressures to be experienced.

With reference to the kits of the second aspect of the invention, their advantage, compared with the individual precursor pipes of the first aspect of the invention is that, being more than one in number, they provide a repair kit which is suitable for use with more than one type of diesel engine. In general, the injector pipes of diesel engines differ one from another in the size of the fittings carried by their end portions for connection respectively with the fuel pump and with the injectors. Thus, for example, in a kit of the invention comprising two precursor pipes, one of the pipes can carry fittings to interconnect a fuel pump whose exit is of 12mm size and whose injector inlet is of 14mm size, while the second precursor pipe has fittings on its end portions for connection with a fuel pump exit and an injector inlet each of 14mm size.It has been found according to the present invention that a kit comprising four precursor pipes is sufficient for use with any of the diesel engines of lorries at present on the market in the United Kingdom.

There is now described, by way of example and with reference to the accompanying drawings, an embodiment of a ket according to the first aspect of the invention, the kit comprising four individual precursor injector pipes according to a preferred embodiment of the second aspect of the invention. In the drawings: FIGURE 1 is a perspective view of a first precursor injector pipe whose end fittings are each of 12mm size; FIGURE 2 is a precursor injector pipe similar to that of Figure 1 but whose end fittings are each of a size 14mm; FIGURE 3 is a perspective view of a precursor injector pipe similar to that of Figure 1 but whose upper end fitting is of 12mm size and whose lower end fitting is of 14mm size; FIGURE 4 is a perspective view of a precursor injector pipe for use on diesel engines sold by Ford Motor Company.The upper end fitting , which has a special design to enable it to be fitted to injectors of Ford diesel engines, is of 14mm size and the lower end fitting is of 12mm size.

With particular reference to Figure 1, the precursor injector pipe comprises a length of straight tubing (10) formed from steel of hydraulic quality.

This tubing is that having an outside diameter of 6.00mm and wall thickness of 2.00mm of the table referred to above.

The precursor injection pipe is designed to inter-connect a fuel pump having a 12mm exit and an injector having a 12mm inlet. The upper and lower fittings (11,12) at the ends of the tubing (10) are of standard design as supplied with conventional injector pipes , comprising a nipple, hexagonal internally threaded captive nut and dust cap received therein.

The precursor injector pipe of Figure 1 can be used to replace a broken injector pipe as follows.

The broken injector pipe (or the remaining parts thereof where the pipe has become severed) is removed from the exit of the fuel pump and from the inlet of the respective injector. There is then removed from one end of the precursor pipe the dust cap, and the associated captive nut is manually advanced along the tubing (10) until its annular flange engages the shoulder of the nipple. The free end of the nut is then presented to the free end of the fuel pump exit and threaded thereon to provide a secure union. Tubing (10) is then manipulated manually so that the other end of the precursor pipe can be brought into the vicinity of the inlet of the injector to be connected. The dust cap at that end of the tubing is removed and the captive nut is advanced until its annular flange engages the shoulder of the nipple.Any further manual shaping of the tubing(10 )necessary is then effected so that the captive nut can be presented to the injector inlet and threadedly engaged with it so as to provide a secure union.

Owing to the particular properties of the tubing (TO )referred to above, the manual shaping of the tubing into the desired shape so as to provide a replacement injector pipe can readily be effected.

The precursor tube of Figure 2 is similar in construction and use to that of Figure 1 except that it is for use in the interconnection of a fuel pump outlet and an injector inlet each of 14mm size.

The precursor pipe of Figure 3 is similar in construction and use to that of Figure 1 except that it is for use either with a fuel pump having a 12mm outlet and an injector having a 14mm inlet or with a fuel pump having a 14mm outlet and an injector having a 12mm inlet.

The kits of this invention comprise two, three, four or more precursor injector pipes. In general, the preferred number of precursor pipes in a kit is in the range from two to six. However, with regard to the diesel engines at present on the market in the United Kingdom it has been found sufficient for the kit to consist of four pipes, for example those described above with reference to the accompanying drawings. The respective precursor pipes constituting a kit are conveniently of the same length and of the same overall shape.

As an additional convenience to the user the kit may contain one, two or more lengths of replacement high pressure hose for use in the repair of pneumatic (or vacuum) or hydraulic brake lines or other pneumatic, vacuum or hydraulic lines of a diesel vehicle.

The precursor pipes of the present invention can be of any convenient length; a suitable length by way of example is 750mm.

As stated above, the end fittings of the precursor pipes can be of a standard design as supplied with conventional injector pipes. In conventional injector pipes the nipples are normally secured to the respective end portions of the tubing by flaring the latter, and that technique can be used in the present invention.

However, it is preferred to secure the nipples to the end portions of the tubings by means of silver solder.

The tubing used in the precursor tubes described above with reference to the accompanying drawings has the following physical properties: Yield : 284/299 N/mm2 Ultimate tensile strength : 366/378 N/mm2 Elongation : 47/49 % on 5D Hardness : VPN The steel from which the tubing had been manufactured had the following analysis: 70 C 0.06 Si 0.03 Mn 0.47 P 0.011 S 0.006

Claims

CLAIMS 1. A precursor injector pipe which comprises a length of fuel supply tubing the end portions of which carry connection means which permit said end portions to be connected respectively to the fuel pump and to a fuel injector of a diesel engine, the fuel supply tubing being of a material such that the tubing can be manipulated manually into a shape which permits said connection of the tubing end portions to the fuel pump and to said injector.
2. A precursor injector pipe according to Claim 1, which is in linear form.
3. A precursor injector pipe according to Claim 1 or 2, in which said material is a steel of hydraulic quality.
4. A precursor injector pipe according to Claim 3, in which the steel is one having a yield in the range from 284 to 299 N/mm2.
5. A precursor injector pipe according to Claim 3 or 4, in which the steel is one having an elongation in the range from 47 to 49% on 5D.
6. A precursor injector pipe according to Claim 3, 4 or 5, in which the steel is one having an ultimate tensile strength in the range from 366 to 378 N/mm2.
7. A precursor injector pipe according to any of the preceding claims, in which the tubing has an outside diameter of about 6mm and a wall thickness of about 2mm.
8. A precursor injector pipe according to Claim 1, substantially as described herein with reference to the accompanying drawings.
9. A precursor injector pipe substantially as described herein and substantially as shown in Figure 1, 2,3 or 4 of the accompanying drawings.
10. A kit for use in the repair of a diesel engine, which comprises two or more precursor injector pipes as claimed in any of the preceding claims, selected so as to fit, respectively, two or more of the fuel injectors of the diesel engine.
11. A kit for use in the repair of a diesel engine, which comprises: two or more precursor injector pipes adapted respectively to fit two or more combinations of fuel pump and fuel injector, each precursor being sufficiently flexible as to be formable by hand into an injector pipe of a suitable shape to permit the inter-connection of the fuel pump and said fuel injector.
12. A kit according to Claim 10 or 11, in which the precursor injector pipes are all of the same shape.
13. A kit according to Claim 12, in which said shape is linear.
14. A kit according to any of Claims 10 to 13, in which the number of precursor injector pipes is in the range 2 to 6.
15. A kit according to Claim 10 or 11, substantially as described herein with reference to the accompanying drawings.
16. A method of providing an injector pipe to interconnect the fuel pump of a diesel engine and one of the fuel injectors of the engine, which comprises: selecting a precursor injector pipe as claimed in any of Claims 1 to 9; manually shaping the precursor injector pipe into a shape at least approximating to the shape of the intended injector pipe; connecting a first end of the precursor injector pipe to one of the fuel pump and the injector; completing, if necessary, the shaping of the precursor injector pipe; and connecting the second end of the precursor injector pipe to the other of the fuel pump and injector.
17. A method according to Claim 16, substantially as described herein with reference to the accompanying drawings.