Trowelling

A rack and frame press uses heavy nylon cloth positioned in a wooden frame inside a rack. A measured amount of apple or other fmit mash is added from a hopper above the frame. The mash is leveled with a hand trowel and the edges of the nylon cloth are folded over the mash to encase it and create a cheese. The frame is removed, and a second rack is placed on top of the first cheese the process is repeated until a stack of cheeses is prepared. A hydrauhc ram then appHes gradually increa sing pressure on the stack and expresses the juice. A high yield of juice (80%) is obtained and no press aid is required. Because this process is labor intensive (17), it is mostly used for small farm and pilot-plant operations. 

Products. Damping treatments are available from many manufacturers in sheet form, as tapes for adhering to a surface, and in bulk form for spraying or troweling onto a surface. Laminated glass is available from many glass suppHers (see Laminated materials, glass). 

Finish removers are appHed by bmshing, spraying, troweling, flowing, or soaking. Removal is by water rinse, wipe and let dry, or solvent rinse. Removers may be neutral, basic, or acidic. The viscosity can vary from water thin, to a thick spray-on, to a paste trowel-on remover. The hazard classification, such as flammable or corrosive, is assigned by the U.S. Department of Transportation (DOT) for the hazardous materials contained in the remover. 

Sodium hydroxide, potassium hydroxide, or other caustic compounds are blended to make these types of removers. Polymer-type thickeners are added to increase the viscosity that allows the remover to be appHed with a bmsh, trowel, or spray. Some of these products use a paper or fabric covering to allow the remover finish mixture to be peeled away. The most common appHcation for this group of removers is the removal of architectural finishes from the interior and exterior of buildings. The long dwell time allows for many layers of finish to be removed with one thick appHcation of remover. 

External coils spaced away from the tank wall exhibit a coefficient of around 5.7 W/(m -°C) [1 Btu/(h-ft of coil surface-°F)j. Direct contact with the tank wall produces higher coefficients, but these are difficult to predict since they are strongly dependent upon the degree of contact. The use of beat-transfer cements does improve performance. These puttylike materials of high thermal conductivity are troweled or camked into the space between the coil and the tank or pipe surface. 

Kelle,/. ladle scoop trowel, kellen, v.t. ladle. 

Spatel, m. spatula trowel surfacer, spatelformig, a. spatula-shaped, spatulate. Spatelmesser, n, steel spatula (shaped Uke a knife). 

In recent years, more heavily filled flowing epoxy resin mortar flooring systems laid at 3 to 5 mm thickness are increasingly being used instead of the more traditional trowelled epoxy resin mortar flooring systems described below. The laying costs of the flowing mortars are... 

Table 9.1 Abrasion values of trowelled epoxy resin flooring compositions, using BS 416...

Two-pack epoxy Section 12.3.3. These are widely used to give the maximum protection to concrete surfaces, floors and walls. They can be applied as relatively thin coatings by spray or as thick epoxy surfaces applied by trowel. In all cases, the application must be preceded by adequate surface preparation (see Section 12.6.1). To allow maximum penetration into the concrete the first coat must have a low viscosity. Coal tar epoxies are used where protection is the main requirement. 

Thin coating Trowelled coatings Self-leveling screeds... 

Trowelled coatings There are a number of proprietary products available but the majority are based on epoxy resins and applied at thicknesses ranging from 0.5 to 5 mm, depending on exposure requirements. 

Various thermosetting and thermoplastic resins BS 3900 Powder/liquid system in factory. Airless spray/trowel in field Superior chemicai and abrasion resistance compared with enamels. Comparatively expensive. Simultaneous coating internally/externally possible. Various resins available to suit particular requirements. 

FBE-coated pipe requires careful handling from factory to the pipe trench to avoid mechanical damage. Repairs are undertaken with either trowel or brush-applied, liquid two-pack epoxy resin-based paints or by melt sticks of compressed powder. 

The simplest adequate sampling device should be used. Where the contaminant Is believed to be on the surface, a soil punch or trowel may be used. If the contaminant Is soluble or Is expected to be located more than a meter below the surface, a truck mounted core sampler such as a split spoon sampler should be used. 

The method above, however, is not suitable when one needs a precise study of the vertical distribution of pesticides. Generally, the concentration of pesticides in paddy sediment is highest at the surface. Special care is required to avoid contamination with surface soil when the sediment is collected. The sediment core should be collected in two stages. First, a pipe with a diameter greater than that of the core sampler is inserted in the sediment and then water inside the pipe is removed gently with a syringe, pipet, etc. Next, a layer of surface soil (1-3 cm) is taken with a spatula or a trowel and then subsurface soil is collected with a core sampler to the desired depth see also Figure 4. 

It is useful to check for the existence of gravel or stones in the sediment beforehand since these may obstruct the insertion of a sampling borer. Putting a pipe with a length of approximately 30 cm and diameter 20-30 cm into sediment makes it easy to collect surface sediment. It is best to collect sediment with a trowel or a spatula after water inside the pipe has been removed. 

To Drs. Denis Burkitt and Hugh Trowell, who have given me a unique perception of the correlation of health and disease with food, and to Drs. John Farquhar and David Jenkins, who always inspire me with their work on the relation of diet to chronic diseases. 

Coatings are applied to the outside or inside of the foundation, creating a radon-resistant barrier between the source and the inside of the home. They come in a wide variety of materials including paint-like products that can be brushed on the interior of the foundation, tar-like materials that are applied to the outside, and cementitious materials that can be brushed or troweled on. They cannot be applied to the underside of the concrete floor slab for obvious reasons, so they must be applied to the inside surface of the slab. The effective life of an interior coating can be greatly diminished by damage therefore, care must be taken to provide protection to the material used. 

Trowell H. 1976. Definition of dietary fiber and hypotheses that it is a protective factor in certain diseases. Am J Clin Nutt 29 417 127. 

For facilities susceptible to nitrocellulose, single base and multibase dusts, the same details could be used with the addition of alternate basic construction types. Six types of construction were chosen which included wood frame, concrete masonry units, reinforced concrete, modified preengineered buildings, fiberglass reinforced plastic and sandwich panels. These were chosen for development of architectural details similar to those mentioned above for nitroglycerin facilities except troweled-on conductive floor lining was to be used instead of lead. 

In the first year, potato tubers and young plants of brassicas, zucchini, and pumpkins can be planted through the mulch into the soil, in pockets loosened with a trowel mix in some compost if available. Initially, plants may need more frost protection than usual, as the mulch cuts off some of the warmth of the sun, making the soil radiate back less heat at night. Cover plants with horticultural fleece alternatively, plant a little later in the year. 

Sir Richard Doll, foreword to Dietary Fibre, Fibre-depleted Foods and Disease (Trowell et al., 1985)... 

Lightweight concrete is usually sprayed on, but may be troweled or formed-in-place using reinforcing mesh. Pneumatically applied material is about 20% heavier than poured-in-place lightweight concrete. As with all concretes, moisture creates a corrosive condition at the surface of the steel. Protective coating of the substrate surface is needed to protect against corrosion. 

Mastics are sprayed on a substrate in one or more coats, depending on the desired degree of fire resistance. The final coat of all fireproofing mastics should be rolled or brushed to provide a smooth surface finish. The material should be applied with a sufficient number of coats to prevent running or slumping and sufficient drying time should be allowed between coats. Mastics may also be hand-troweled, if permitted in the manufacturer s specifications. 

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