BENEFITS
Parmiter Flexible Chain Harrows.
The chain harrow is one of the few farm implements that has not changed in over 100 years. Its main job then as now was to clear the meadows/fields of dead grass, moss, spread the mole hills and residual manure. They can also be used on arable land for covering in behind drills and weeding.
Good grass doesn’t just grow out of the ground it needs nurturing and encouraging, with good pasture management.
Part of this and probably the most important, is the clearing out of all the rubbish that has built up over the autumn and winter months and the major time of use is in the spring. The job of the harrow is to drag out all the moss and thatch that is lying on the surface, which then allows the light and air to get down to the soil. By opening up the surface of the grass you also stop the spread of moss which if left can eventually take over from the grass and this will reduce yields and the crop quality when silaging. Also, the action of the tines scratching the soil surface allows the light and moisture to get to the root structure of the grass which in turn encourages new growth to emerge. Another function of the harrow is to spread and break up any residual manure that has been left on the field, which will then wash down and break up more easily when it rains, again feeding the new growth. This operation ahead of the fertilizer application makes sure that the granulated fertilizer actually gets to the plant structure and doesn’t just sit on the top.
Parmiter offer a range of harrows for grass and arable applications, the main difference between the two is the length of the tine. You need a longer tine for arable, to produce a tilth, and a shorter tine for grass depending on the job required.
Key points when operating chain harrows:
1. The most important thing to remember with any chain harrow is that the maximum working speed should not exceed 31/2 to 4 mph. This may seem slow, but if you consider that the harrow was first designed to be pulled behind the horse, that is the average working speed of a horse. The horse may have changed but the basic product hasn’t and all the design and working methods are based around this speed. Go any faster and whilst you may make nice green stripes you will not be doing any good because the harrow will merely bounce over the surface and be ineffective.
2. Having got the speed right, it is now very important to make sure the harrows are pulled in the right direction. Whilst this may seem obvious, it isn’t because if you look at the design of the harrow it should be pulled by the large ‘V’ puller at the front, in other words directly behind the towing bar or mounted frame. To the untrained eye this looks like the harrow tines will open but the harrows are made of high grade carbon steel and the action of them springing back closed helps with the operation of the harrow (as an aside this is why they are very difficult to repair as welding doesn’t hold the links very well, hence you have to replace the links and use heat to bend them in place). The effect is to push down on the link following and this in turn forces the next row of tines into work and so on. If you pull them by the small ‘V’ puller, the tines look as though they will stay closed, however this will have the affect of pushing up on the link following and will force the next row of tine out of work and so on. If you try this with a trailed set of harrows they will try and roll back towards the tractor, and the harrows will jump up and down in work.
3. Now you have the forward speed and the direction of travel correct you need to explain the reason for the harrows being pulled at a 5 degree angle. This is achieved on the poles by having the chains that connect the pole to the tractor, at different lengths, on the mounted frames one of the lower link pins is set forward of the other. The harrows are pulled at this angle to ensure that all the tines are actually working the ground and not tracking one behind the other.